NOAA CORAL REEF GRANT PROGRAM PROJECTS TO IMPROVE OR AMEND CORAL REEF FMPs NA08NMF4410463
Validation of a Spawning Aggregation of Mutton Snapper and Characterization of the Benthic Habitats and Fish in the Mutton Snapper Seasonal Closed Area, St. Croix, U.S. Virgin Islands Submitted to: Caribbean Fishery Management Council San Juan, Puerto Rico Barbara L. Kojis and Norman J. Quinn
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Date: 15 February 2011
Table of Contents List of Tables ................................................................................................................................. iii List of Figures ................................................................................................................................. v EXECUTIVE SUMMARY ............................................................................................................ 1 CHAPTER 1 ................................................................................................................................... 4 Mutton Snapper (Lutjanus analis) Spawning Aggregation in the Mutton Snapper Seasonal Closed Area, St. Croix, U.S. Virgin Islands ................................................................................... 4 INTRODUCTION ...................................................................................................................... 4 MATERIALS AND METHODS ................................................................................................ 9 Fishing Dates and Methods ..................................................................................................... 9 Scuba Diving Searches for Lutjanus analis .......................................................................... 11 Fish Abundance Assessment by Fishing Effort .................................................................... 12 Biometric Analysis................................................................................................................ 12 Sex Determination ................................................................................................................ 13 Fecundity and Oocyte Size Distribution ............................................................................... 13 Otoliths, Diet, and Genetic Samples ..................................................................................... 14 RESULTS ................................................................................................................................. 16 Catch Results in the Mutton Snapper Seasonal Closed Area ............................................... 16 Reproductive Aspects ........................................................................................................... 21 Length Weight Relationship ................................................................................................. 25 Fecundity and Egg Size Distribution .................................................................................... 26 DISCUSSION ........................................................................................................................... 30 Spawning Season .................................................................................................................. 30 Spawning Aggregation Location .......................................................................................... 32 Status of the Mutton Snapper Aggregation ........................................................................... 33 Size at Onset of Reproduction .............................................................................................. 34 Maximum Length and Age ................................................................................................... 35 Sex Ratio ............................................................................................................................... 36 Fecundity............................................................................................................................... 36 Conclusions ........................................................................................................................... 37 LITERATURE CITED - CHAPTER 1..................................................................................... 39 APPENDIX 1 ............................................................................................................................ 44 CHAPTER 2 ................................................................................................................................ 45 Habitat Description of the St. Croix, U.S. Virgin Islands Mutton Snapper Seasonal .............. 45 INTRODUCTION .................................................................................................................... 45 METHODS - BENTHIC SURVEY.......................................................................................... 52 RESULTS – BENTHIC SURVEY ........................................................................................... 53 i
Prada (2003) Habitat Type - Submerged Aquatic Vegetation on Unconsolidated Sediments ............................................................................................................................................... 54 Prada (2003) Habitat Type - Bare or Mixed Invertebrate on Unconsolidated Sediments .... 61 Coral and Gorgonians on Consolidated Sediments .............................................................. 65 DISCUSSION - BENTHIC SURVEY ..................................................................................... 76 WATER TEMPERATURE ON ST. CROIX ........................................................................... 78 INTRODUCTION .................................................................................................................... 78 MATERIALS AND METHODS - TEMPERATURE ............................................................. 78 RESULTS - TEMPERATURE ................................................................................................. 78 DISCUSSION - TEMPERATURE........................................................................................... 80 LITERATURE CITED - CHAPTER 2..................................................................................... 81 APPENDICIES CHAPTER 2 ....................................................................................................... 83 Appendix 1 - Abstract 63rd Gulf and Caribbean Fisheries Institute Meeting ............................... 84 Appendix 2 - Summary of Benthic Habitat Analysis: Benthic Categories ................................... 85 Appendix 3 - Summary of Benthic Habitat Analysis: Coral Species ........................................... 94 CHAPTER 3 ................................................................................................................................. 99 Habitat Focused Fish Surveys in the Mutton Snapper Seasonal Closed Area ............................. 99 INTRODUCTION .................................................................................................................... 99 MATERIALS AND METHODS ............................................................................................ 100 Fish and Caribbean Spiny Lobster and Queen Conch Transects ........................................ 100 Roving Fish Censuses ......................................................................................................... 101 Fish Biodiversity ................................................................................................................. 101 RESULTS ............................................................................................................................... 102 Habitat Overview ................................................................................................................ 103 Habitat Summaries .............................................................................................................. 104 Population Abundance of Marketable Fish......................................................................... 109 DISCUSSION ......................................................................................................................... 114 Commercially Harvested Fish Recorded in the MSSCA .................................................... 114 LITERATURE CITED ........................................................................................................... 119 APPENDICIES - CHAPTER 3 .................................................................................................. 121 Appendix 1: List of Presence / Absence of Fish Species by Habitat ...................................... 122 Appendix 2: Benthic Transect Fish Abundance by Habitat................................................... 134 Appendix 3 - Queen conch (Strombus gigas) Distribution and Abundance in MSSCA Habitats ................................................................................................................................................. 166 Appendix 4 - Abstract 63rd Gulf and Caribbean Fisheries Institute Meeting ......................... 169 CHAPTER 4 ............................................................................................................................... 170 Pilot Study of Back Reef Embayments and Bays on the East End of St. Croix as post settlement habitat for juvenile grouper and snapper .................................................................................... 170 INTRODUCTION .................................................................................................................. 170 MATERIALS AND METHODS ............................................................................................ 173 Chenay Bay ......................................................................................................................... 174 Robin Bay and Rod Bay ..................................................................................................... 178 ii
RESULTS ............................................................................................................................... 182 Chenay Bay ......................................................................................................................... 182 Robin Bay ........................................................................................................................... 191 Other Sites Surveyed........................................................................................................... 202 D ISCUSSION ........................................................................................................................ 204 LITERATURE CITED ........................................................................................................... 207 RECOMMENDATIONS ............................................................................................................ 209 ACKNOWLEDGEMENTS ........................................................................................................ 211
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List of Tables: Mutton Snapper (Lutjanus analis) Spawning Aggregation
List of Tables Table 1.1
Days fished for Lutjanus analis in the Mutton Snapper Seasonal Closed Area in relation to full moon.
Table 1.2
Ratio of number of male to number of female Lutjanus analis caught in Mutton Snapper Seasonal Closed Area during the area and seasonal closures in 2009.
Table 1.3
Mean GSI and standard error (SE) for males (♂) and females (♀) and mean fork length and range of FL of Lutjanus analis.
Table 1.4
Months with documented spawning of Lutjanus analis from the Caribbean. Primary spawning months in St. Croix are shown in capitals.
Table 1.5
Days spawning documented for mutton snapper (Lutjanus analis) in relation to lunar phase.
Table 1.6
Mutton snapper (Lutjanus analis) size and age at maturity various locations.
Table 1.7
Number of eggs produced by female mutton snapper (Lutjanus analis).
Table 2.1.
Hierarchical classification scheme developed by Prada (2003) to generate detailed habitat maps around the USVI.
Table 2.2.
Total area of benthic habitats for the MSSCA.
Table 2.3.
Comparison of the percentage of invertebrate and substrate cover habitat classifications (Prada 2003) in the MSSCA.
Table 2.4.
Mean monthly subsurface seawater temperature in the MSSCA in 2009 and 2010.
Table 3.1.
Summary of fish transect data in the Mutton Snapper Seasonal Closed Area.
Table 3.2.
Summary of roving fish surveys in the Mutton Snapper Seasonal Closed Area.
Table 3.3:
List of the species recorded in roving this study that are marketable fish species on St. Croix.
Table 3.4:
Number of individuals 100m-2 of marketable species in each commercially harvested family recorded in Mutton Snapper Seasonal Closed Area (MSSCA) habitats.
Table 3.5:
Estimate of total number of marketable fish by family in the Mutton Snapper Seasonal Closed Area based on the number of fish 100m-2 and size of habitat.
Table 4.1. Summary of sites surveyed in Chenay Bay, north shore, St. Croix, U.S. Virgin Islands. Table 4.2.
Summary of sites surveyed in Robin Bay, south shore, St. Croix, U.S. Virgin Islands on July 13, 2009.
Table 4.3.
Mean percent cover of various biotic and abiotic habitat components at six sites in Chenay Bay, St. Croix, U.S. Virgin Islands.
Table 4.4.
Fish species, including maturity stages, recorded at the two outer Chenay Bay sites. iii
List of Tables: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Table 4.5.
Snapper and commercially important grouper species and life stages recorded at the five sites surveyed during 15 minute roving fish surveys in the inner part of Chenay Bay, St. Croix, USVI.
Table 4.6.
Fish species and life stages recorded in transect surveys at four sites in inner Chenay Bay, St. Croix, USVI.
Table 4.7.
Mean percent cover of various habitat components at three sites in Robin Bay, St. Croix, U.S. Virgin Islands. Sites were sampled on July 13, 2009.
Table 4.8.
Back reef crest habitat in Robin Bay, St. Croix (RB3).
Table 4.9.
Robin Bay: Summary of species and life stages of fish observed at three sites in Robin Bay, St. Croix, USVI.
Table 4.10. Robin Bay, St. Croix, USVI: Percentage of each developmental stage recorded based on morphology (especially Labridae and Scaridae) and/or size.
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List of Figures: Mutton Snapper (Lutjanus analis) Spawning Aggregation
List of Figures Figure 1.1
Location of the Mutton Snapper Seasonal Closed Area in the southwest corner of the St. Croix shelf, including latitude and longitude.
Figure 1.2. Cast net was used to catch the bait fish. Figure 1.3. Gerson Martinez and Dr. Norman Quinn searching for mutton snapper spawning aggregation in the MSSCA in the outer shelf. Figure 1.4. Garmin MapSource Map showing some of the mutton snapper search tracks within and to the west of the Mutton Snapper Seasonal Closed Area. Figure 1.5. Mutton snapper were measured, weighed and dissected to remove gonads, stomachs and provide genetic samples. Figure 1.6. Eggs from Lutjanus analis caught 11 May 2009 showing size range of eggs. Figure 1.7. Otoliths were removed by cutting through the head just behind the operculum. Figure 1.8. Catch per unit effort for all fish and Lutjanus analis caught in the Mutton Snapper Seasonal Closed Area in 2009 during the three months of the seasonal closure. Figure 1.9. Large school of cubera snapper (Lutjanus cyanopterus) at Nicky's reef, St. Croix. Figure 1.10. School of Atlantic spadefish (Chaetodipterus faber) hovering in water column at Nicky's reef, St. Croix. Figure 1.11. Schools of fish and conch at Nicky's reef near the Red Buoy. Figure 1.12. Lutjanus analis - Mean gonad somatic index with Standard Error bars. Figure 1.13. Lutjanus analis ♀: Linear regression of GSI based on fork length. Figure 1.14. Lutjanus analis ♂: Linear regression of GSI based on fork length. Figure 1.15 Length frequency of analysis of female (a) and male (b) mutton snapper (Lutjanus analis) in April, May and June 2009. Figure 1.16. Estimated size of first maturity of mutton snapper (Lutjanus analis) using logistic regression. Figure 1.17. Length weight relationship for male and female Lutjanus analis. Figure 1.18. Sample from an ovary of a Lutjanus analis caught 11 May 2009 showing size range of eggs. Figure 1.19. Egg size distribution from representative ovaries of individuals of Lutjanus analis. Figure 1.20. Fecundity of Lutjanus analis by fork length by month. Figure 2.1. Mutton Snapper Closed Area off St. Croix, USVI including latitude and longitude of boundaries. Figure 2.2. Example color bathymetry near the edge of the island shelf in the MSCA. Figure 2.3. Multi-beam side scan sonar image of Mutton Snapper Closed Area. v
List of Figures: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Figure 2.4. Side scan sonar mosaic showing sandy moat between two reefs. Figure 2.5. Classification of benthic habitats in MSSCA. Figure 2.6. Dendrogram of CPCe benthic categories by habitat matrix Figure 2.7. ALIN 1 - Clypeaster rosaceus test. Figure 2.8. Side Scan Sonar images of ALIN generally show few features. Figure 2.9. ALIN 2 site in July 2, 2009 showing the sandy bottom interspersed with algal clumps. Figure 2.10. Variation in ALIN 1 identified area is demonstrated in this photo by the lack of macro algae on the substrate. Figure 2.11. SPAL 1 - Clypeaster rosaceus were abundant (left) in this habitat. Figure 2.12. Close up of SPAL site showing high cover of macro and turf algae. Figure 2.13. SPAL habitat showing lack of vertical relief, no live gorgonians, a solitary vase sponge and dense cover of macro and turf algae. Figure 2.14. Prada (2003) suggested that the dark and light bands in the side scan sonar images corresponded to the algae and sand respectively. Figure 2.15. SSS images from Prada (2003) show the uniform dark signal (a) which was interpreted as dense algae. Figure 2.16. 2009 photo showing DEAL habit void of dense meadows of fleshy algae. Figure 2.17. Coral rubble and remnants of Acropora cervicornis on the sandy bottom in DEAL in 2009. Figure 2.18. SANR is dominated by a sandy substrate with sporadic patches of turf algae / cyanobacteria and small clumps of limestone. Figure 2.19. Queen conch, Strombus gigas, was commonly observed in SANR. Figure 2.20. Film of cyanobacteria covers much of SANR and DEAL habitats. Figure 2.21. Prada (2003) notes that the lack of large macro invertebrates in SANR results in a lack of habitat complexity and strong continuous reflections from the sand. Figure 2.22. SAIN habitat had sandy patches over pavement with occasional gorgonians, sponges, and live and dead coral heads. Figure 2.23. Side Scan Sonar images show irregularities caused by invertebrate and limestone clumps. Figure 2.24. Sand and Acropora cervicornis rubble dominant SARI habitat in 2009. Figure 2.25. Sharp interface between SARI habitat on the right and GOPL habitat on the left. Figure 2.26. Sand with ripple marks but had distinct discontinuities in the SSS imagery. Figure 2.27. Deep groves between limestone spurs were characteristic of coral limestone habitat. Figure 2.28. High relief is visible in the coral limestone (COLI) habitat. vi
List of Figures: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Figure 2.29. The edge of reef with coral colonies overhanging sand channel, creating ledges. Figure 2.30. Montastrea annularis species complex coral head showing live fragments with partial mortality of the coral colony. Figure 2.31. The high vertical relief in the coral limestone habitat is easily recognized in the side scan sonar images. Figure 2.32. Habitat observed at GPS coordinates for COPA 1 in June 2010. Figure 2.33. Spiny lobster being photographed in the COPA habitat as it leaves its den in the depression at the right middle of the photograph. Figure 2.34. Side Scan Sonar of COPA from Prada (2003). Figure 2.35. Pavement in sites designated COPA by Prada (2003) is disrupted by these depressions which are often surrounded by ledges and contain sand and coral rubble. Figure 2.36. GOPL habitats were distinct from adjacent habitats. Figure 2.37. Sponges and gorgonians stand out among the macro algae covering the dead coral colonies in GOPL 1. Figure 2.38. According to Prada (2003) GOPL did not present a distinct boundary with its adjacent habitats. Figure 2.39. White plague diseased Montastrea annularis at GOPL 4. Figure 2.40. Healthy population of Acropora cervicornis in GOPL. Figure 2.41. The lionfish, Pterois volitans, an invasive species, observed in GOPL at 18m. Figure 2.42. A nurse shark, Ginglymostoma cirratum, observed cruising over GOPL habitat. Figure 2.43. Mean subsurface sea water temperature during dives in May 2009 and June 2009. Figure 2.44. Subsurface sea water temperatures warmer in 2010 during the period of closure. Figure 3.1. Dendrogram of habitats using Agglomerative Hierarchical Clustering (XLSTAT 2010). Figure 4.1. Map of the St. Croix East End Marine Park. Figure 4.2. Google Earth image of the East End of St. Croix showing location of Rod Bay and Robin Bay Figure 4.3.
NOAA NOS habitat map encompassing Chenay Bay showing habitat breakdown.
Figure 4.4.
Google Earth map showing approximate locations of sample sites.
Figure 4.5.
Google Earth map showing location of survey sites in inner Chenay Bay.
Figure 4.6.
NOAA NOS habitat map of Robin and Rod Bays, south coast St. Croix.
Figure 4.7.
Robin Bay, St. Croix with the location of the three sites surveyed marked.
Figure 4.8.
Robin Bay, St. Croix with using the new Google Maps image with the three sites surveyed marked by the approximate coordinates. vii
List of Figures: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Figure 4.9.
Representative photos showing the type of habitat found in CBP1 in the outer part of Chenay Bay, St. Croix, USVI.
Figure 4.10. Representative photos of habitat found in CBSG2 in the outer part of Chenay Bay. Figure 4.11. Inner Chenay Bay, St. Croix, USVI - CBSG3, continuous seagrass habitat with >75% cover of seagrass. Figure 4.12. Sand and sand/coral rubble habitat characteristic of CBSG4 in inner Chenay Bay, St. Croix, USVI. Figure 4.13. Inner Chenay Bay, St. Croix USVI - Photos representative of CBSG5 showing patchy seagrass habitat with seagrass comprising 30-50% cover. Figure 4.14. Photos of consolidated coral rubble habitat characteristic of CBP6 in inner Chenay Bay, St. Croix, USVI. Figure 4.15. Left: Dense seagrass habitat (similar to RB1) near back reef crest community (RB3) dominated by Thalassia testudinum. Figure 4.16. Back reef crest habitat in Robin Bay, St. Croix (RB3). Figure 4.17. Rubble habitat near back reef in Robin Bay, St. Croix (RB3). Figure 4.18. Back reef crest habitat in Robin Bay, St. Croix (RB3): Large Porites furcata reef. Figure 4.19. Back reef crest habitat in Robin Bay, St. Croix (RB3): Montastrea annularis and M. faveolata patch reefs. Figure 4.20. Back reef crest habitat in Robin Bay, St. Croix (RB3): partial mortality of Montastrea annularis colony. Figure 4.21. Rod Bay, St. Croix: Juvenile lane snapper, blue tang, and grunts in a dead Porites patch reef. Figure 4.22. Rod Bay, St. Croix: Juvenile mahogany and schoolmaster snapper, school of blue tang, and several squirrelfish on largely dead reef in outer part of the bay. Figure 4.23. Cotton Garden Bay: Juvenile snapper within or adjacent to dense seagrass are invariably associated with coral rubble. Figure 4.24. Western shoreline of St. Croix: juvenile lane snapper.
viii
Executive Summary
EXECUTIVE SUMMARY This report describes the first study of the mutton snapper spawning aggregation within the Mutton Snapper Seasonal Closed Area (MSSCA), St. Croix, U.S. Virgin Islands and provides the first characterization of the habitat and habitat associated fish and invertebrate populations in the MSSCA. Mutton snapper (Lutjanus analis) is highly prized by commercial and recreational fishers in the US Caribbean (Puerto Rico and the U.S. Virgin Islands) because of its good quality flesh and reports that it is seldom ciguatoxic. It is susceptible to targeted fishing by recreational and commercial fishers because it aggregates to spawn at predictable times and locations. Based largely on information provided by the Virgin Islands Department of Planning and Natural Resources, Division of Fish and Wildlife, the Caribbean Fishery Management Council (CFMC) and the Federal Government declared an area south of St. Croix seasonally closed from March 1 – June 30th commencing in 1993 to protect a spawning aggregation of mutton snapper south of St. Croix from fishing. In 1994, the Government of the U.S. Virgin Islands (USVI) followed with a similar declaration, resulting in a 2 nm sq. area seasonally closed to fishing. This area became the MSSCA. Owing to concerns about the status of the mutton snapper because of continued targeting of mutton snapper by fishers in the MSSCA during the closure, the CFMC in 2005 and the USVI in 2006 implemented a seasonal prohibition in federal and territorial waters, respectively, on the harvest of mutton snapper from April 1 – June 30th. To document the mutton snapper spawning aggregation within the MSSCA on St. Croix, we conducted visual censuses using scuba divers from April to July 2009 and May to July 2010, hook and line catches from April to June 2009, and fisher interviews. Based on gonad maturity and the gonad somatic index of mutton snapper caught in the MSSCA and purchased on St. Croix in March 2009 and 2010 and July 2009, this species likely spawns in the vicinity of the MSSCA from April through July each year depending on the timing of the full moon. Individual fish are batch spawners, spawning repeatedly over a period of days or months. The spawning aggregation of mutton snapper in or near the MSSCA appears to be fairly robust based on the high CPUE reported in this study. This is despite fairly heavy fishing pressure that continued until the seasonal prohibition on possession of mutton snapper in territorial and federal waters was implemented 2006. The skewed sex ratio of the catches (2.3 males:1 female), the result of a high proportion of small males, which start reproducing at a smaller size than females, may reflect high fishing pressure before the 2006 seasonal prohibition went into effect and the initial recovery of the population. Given the high female fecundity reported in this study, recovery may occur quickly if fishers continue to respect the seasonal possession prohibition and enforcement is adequate. The actual site of the mutton snapper aggregation still needs to be confirmed. Divers were unable to detect any sign of a spawning aggregation within the MSSCA. Effort should be made to make visual dive inspections of the reefs near the Red Buoy site during the annual spawning period of mutton snapper. Also, visual dive inspections of reefs in this area at the spawning times of other species observed at the site would provide information about the importance of this site for these
1
Executive Summary
species and other species, for example, there have spawning/aggregating in this area (Martinez pers. com.).
been reports of red hind
To verify the habitat mapped by Prada (2003) based on sidescan and multibeam data collected to Geophysics GPR, Inc. (2003) within the MSSCA, photo quadrats were used to describe the habitat. The deep reef slope, reported to once have high coral cover, experienced a sharp die off in the 2005 coral bleaching event and is now dominated by sponge, gorgonian and algal communities with low percent live coral cover. Live scleractinian coral cover was very low. Habitats such as COLI (Coral Limestone - a spur and groove coral community) and GOPL (gorgonian plain - actually a hillocky limestone hard bottom community with abundant gorgonians, sponges and corals - primarily dead coral heads), that had a strong 3D structure created by corals, only had a coral cover of 7.56% and 7.00% respectively. The Montastrea annularis species complex was the dominant coral taxa in both COLI and GOPL habitats. The dead coral skeletons in these habitats had high macro algal cover, primarily Lobophora variegata. In shallower habitats such as ALIN (Algae Invertebrate hard bottom),, Sargassum spp. was more common while Dictyota was most abundant in SAIN (Sand Invertebrates). In the most extensive habitats, the predominately shallow ALIN and SAIN, Siderastrea siderea was the most abundant coral. However, this species only covered 0.96% of the substrate in ALIN and 0.68% in SAIN. The current low coral cover in the MSSCA is largely a function of coral bleaching and disease. Coral bleaching in the USVI is related to higher than normal water temperatures, which in turn is related to global climate change. . An underwater temperature logger was used to monitor subsurface sea water temperatures on dives from April to July 2009 and from May to July 2010. Subsurface sea water temperatures were much warmer in 2010. The mean temperature in May 2010 was 1.61oC warmer than 2009 and June 2010 was 0.91oC warmer than June 2009. It is uncertain how long mutton snapper aggregations will continue to exist in the face of an altered habitat. To describe the fish communities associated with each habitat within the MSSCA visual surveys of fish populations were conducting using roving and transect techniques. The MSSCA harbors a high diversity of fish species. The most abundant fish were the small blue head wrasse and bicolor damselfish. These are important forage fish for groupers and snappers. None of the larger grouper species such as the Nassau and goliath groupers and few of the large snapper and parrotfish (rainbow, midnight and blue) were observed. Surgeonfish comprised slightly over 30% of the maketable species recorded in transects. Carangids (jacks), scarids (parrotfishes), and holocentrids (squirrelfishes), were the next most abundant, comprising 17 - 19% of the marketable species recorded. The groupers (serranids) were the fifth most abundant taxa (7%), primarily because the coney were abundant in all habitats. Only one lionfish was recorded in over 250 dives in 2009 and 2010 in the MSSCA and adjacent areas. However, ominously, the lionfish was detected on one of the last dives conducted for this project in July 2010. The timing of this sighting was consistent with the increasing numbers of lionfish being reported to the VI DPNR Division of Fish and Wildlife by commercial fishers and divers.
2
Executive Summary
Searches were undertaken in the East End Marine Park on St. Croix for juvenile snapper and grouper, with a particular emphasis on searching for juvenile mutton snapper. Intensive searches were done in a variety of habitats in two bays, Chenay Bay on the north shore and Robin Bay on the south shore. Neither bay had high numbers of juvenile snapper and no juvenile grouper were recorded. Most of the juvenile snapper were yellowtail, lane and mahogany snapper. No mutton snapper juveniles were recorded. The highest number juvenile snappers was found along the eroded beachrock south of Frederiksted on the western shore of St. Croix. Schools of primarily lane snapper were present during a snorkel and dive in July 2010. It is possible that the paucity of juveniles of L. analis and commercially important serranid species may be a function of the number of recruits available. Although L. analis is now seasonally protected during its peak spawning months and harvest and possession of E. striatus is prohibited, these management measures have only recently been implemented in both territorial and federal waters. The L. analis seasonal closure appears to be working well with no signs of sale of L. analis during the closure period. Several recommendations for further research are provided at the end of this report. Of special note, further research to find the location of the spawning aggregation and obtain information on trends in the number, size, and sex ratio of fish in the aggregation should be conducted throughout the spawning season. As well, research as to whether mutton snapper males and females spawn in one or more months should be undertaken because it is important in determining the total number of fish in the aggregation.
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Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
CHAPTER 1 Mutton Snapper (Lutjanus analis) Spawning Aggregation in the Mutton Snapper Seasonal Closed Area, St. Croix, U.S. Virgin Islands
INTRODUCTION Mutton snapper (Lutjanus analis) is highly prized by commercial and recreational fishers in the US Caribbean (Puerto Rico and the U.S. Virgin Islands) because of its good quality flesh (Delgado 2004) and reports that it is seldom ciguatoxic (Olsen and Wood 1984). It is often referred to as "virgin snapper" throughout the U.S. Virgin Islands and "sama" on St. Croix where there is a large Hispanic population. "Sama" is the local name for mutton snapper in Puerto Rico (Esteves-Amador 2005). It is also called mutton fish, "pargo", "pargo criollo", and "pargo cebadal" in other parts of the Caribbean (Delgado 2004). It is among the species managed in the Exclusive Economic Zone (EEZ) of the U.S. Caribbean by the Caribbean Fishery Management Council (CFMC) and has been designated an indicator species for Snapper Unit 3 (shallow water snappers) (SEDAR14-SAR2 2007). Snapper Unit 3 includes the gray (L. griseus), lane (L. synagris), dog (L. jocu), schoolmaster (L. apodus), and mahogany (L. mahogoni) snappers (CFMC and NOAA NMFS 2005). Snapper Unit 3 is not listed as overfished or undergoing overfishing by the National Oceanic and Atmospheric Administration, National Marine Fisheries Service (NOAA NMFS) (SEDAR14-SAR2 2007). Mutton snapper is on the International Union for the Conservation of Nature (IUCN) Redlist and was assessed as Vulnerable (applicable criteria: A2d, B1+2e ver.2.3) by Huntsman (1996). This designation means that mutton snapper are considered at high risk of extinction in the wild in the medium-term future. The criteria pertaining to mutton snapper are defined as follows: A2) "A reduction of at least 20%, projected or suspected to be met within the next ten years or three generations, whichever is longer, based on...." "d) actual or potential levels of exploitation." "B) Extent of occurrence estimated to be less than 20,000km2 or area of occupancy estimated to be less than 2000km2, and estimates indicating any two of the following" (B1 and B2e pertain to mutton snapper). B1 = "Severely fragmented or known to exist at no more than ten locations". B2 = "Continuing to decline, inferred, observed or projected, in any of the following:" "e) number of mature individuals" 4
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
B1 is likely incorrect for this species, since mutton snapper range from Massachusetts to Brazil (Anderson 2002 cited in SEDAR14-SAR2 2007) and are apparently genetically homogeneous throughout the northern Caribbean and Florida (Gold pers. com.). Also, mutton snapper are not severely fragmented and certainly exist at more than ten locations. The IUCN assessment is over 14 years old and needs to be updated. Mutton snapper reproduce by gathering seasonally into spawning aggregations at predictable times and locations (Erdman, 1976, Claro and Lindeman 2003, Esteves-Amador 2005, Heyman and Kjerfve 2008). Spawning aggregations of snapper and grouper are vulnerable to targeted fishing by recreational and commercial fishers (Anon. 2004, Beets 1987, CFMC 1993, Claro et al. 2001, Claro and Lindeman 2003, Beets and Friedlander 1992, Nemeth 2005). Targeted fishing of spawning aggregations in the US Virgin Islands (USVI) occurred in the 1960’s and 1970’s resulting in the loss of a Nassau grouper (Epinephelus striatus) aggregation on St. Croix by 1971 and a sharp decline in an aggregation of this species off St. Thomas in 1975-1976 (Olsen and LaPlace 1978) with the eventual loss of the aggregation in the 1980's. Fishers on St. Thomas also targeted a red hind (E. guttatus) aggregation in the vicinity of the Nassau grouper aggregation. Loss of the Nassau grouper spawning aggregation focused the attention of fishers and territorial and federal fisheries management agencies on the importance of protecting aggregations and resulted in seasonal area closure of the red hind (E. guttatus) spawning aggregation south of St. Thomas in 1989 (CFMC 1993). A similar seasonal closure for red hind was instituted on Lang Bank, St. Croix (CFMC 1993 and CFMC and NOAA NMFS 2005). There has been only one reported extinction of shallow water snapper spawning aggregations by fishing. Craig (1966 (abstract seen) cited by Graham et al. 2008), reported the loss of a mutton snapper spawning aggregation in Long Cay, Belize. However, there is other evidence targeted fishing of spawning aggregations has caused the decline of some snapper species, including mutton snapper (Claro et al. 2001, Matos-Caraballo et al. 2006, Graham et al. 2008, Claro et al. 2009). A significant decline in catches of mutton snapper was reported by Puerto Rican fishers (Matos-Caraballo et al. 2006). In Cuba, the highest catches of mutton snapper were often obtained during the reproductive period (April to August) with the peak spawning months of May and June accounting for 35-40% of the annual catch of this species (Claro et al. 2009). Catches of mutton snapper in Cuba were stable until the early 1990's when there were drastic reductions in catches attributed to: 1) a reduction of commercial fishing effort owing to a national crisis that reduced the availability of fishing supplies and gear and 2) the development of an intense subsistence fishery in the Archipelago Sabana-Camaguey that targeted mutton snapper among other species. In 1997-98, catches increased to nearly former levels, but then again declined. Since 1998, annual catches have been slowly declining and were more variable compared to the years prior to 1990 (Claro et al 2009). In 1986, Tobias (referenced in CFMC 1993) wrote a brief report describing fishing on a mutton snapper spawning aggregation on the southwest of St. Croix. The CFMC (1993) reported the following information about the aggregation: Based on information obtained from commercial fishermen and the Division of Fish and Wildlife, U.S.V.I. records from 1981, mutton snapper have been harvested for more than 20 years from the spawning aggregation. The 5
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
aggregation area is located between 2.1 and 3.2 nautical miles southwest of Long Point in 10 to 27 fathoms of water. Most commercial fishing occurs at night by handline fishermen in outboard-powered vessels less than 6 m in length; however, fish traps and most recently gill nets have been used to harvest mutton snapper in this area. Weather permitting, more than 30 fishing vessels can be seen nightly for one week after the full moon during the months of March through June. Fishing effort is most heavily concentrated at depths of 10 to 15 fathoms. Commercial landings indicate that mutton snapper have been fished to the extent that production from the aggregation is declining; catches have been reduced from >500 lbs per boat to <100 lbs per boat for the highliners. Average individual weights have decreased from 10 lbs to 5 lbs during the period reported. According to the CFMC (1993), several dives were conducted by the USVI DPNR/Division of Fish and Wildlife and researchers in the fishing area during daylight hours, but no aggregation was observed. Dives were apparently limited to a depth of 15 fathoms (90ft or 27.4m). It was assumed that the aggregation site was in deepwater off the slope at 27 fathoms (162ft or 49.3m), deeper than the divers had dived. Based on fishing effort, the coordinates of the presumed aggregation area were determined. In December 1993, the US Department of Commerce, based on the recommendation of the Caribbean Fishery Management Council (CFMC and NOAA NMFS 2005), implemented a seasonal closed area, the Mutton Snapper Seasonal Closed Area (MSSCA) to protect the spawning aggregation of mutton snapper in the southwest corner of St. Croix (58 FR 53145) (Fig. 1.1). Because only a portion of the spawning area occurred in federal waters, joint territorial and federal protection was essential to protect the spawning aggregation. In 1994, the USVI government established compatible regulations within their area of jurisdiction to establish a seasonally closed area deemed adequately sized to protect the mutton snapper spawning aggregation (SEDAR14 SAR2 2007, Garcia-Moliner 2009). The joint efforts of the two governments established an annual seasonal closed area for mutton snapper from March 1 to June 30. The mutton snapper spawning aggregation within and outside the MSSCA was targeted by St. Croix fishers for many years, even after the implementation of the prohibition on fishing within the MSSCA. Enforcement of fishing inside the MSSCA was difficult because fishers often targeted the aggregation at night. Some fishers legally fished the aggregation, fishing outside the western boundary of the MSSCA during the spawning season (pers. com.). Fish were apparently drawn to the chum used in the line fishing technique for snappers both inside and outside the MSSCA. In order to increase compliance and improve enforcement, the U.S Department of Commerce in 2005 (50CFR622.33(a)(7)) and USVI Government in 2006 (VIRR 9A 316-14 (c)) implemented regulations to prohibit possession of mutton snapper during the presumed peak spawning months, April 1 to June 30, each year in federal and territorial waters.
6
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Latitude 17°37.8’ N 17°39.0’ N 17°39.0’ N 17°38.1’ N 17°37.8’ N
Longitude 64°53.0’ W 64°53.0’ W 64°50.5’ W 64°50.5’ W 64°52.5’ W
Figure 1.1 Location of the Mutton Snapper Seasonal Closed Area (MSSCA) in the southwest corner of the St. Croix shelf, including latitude and longitude.
The St. Croix spawning aggregation is one of only two confirmed spawning aggregations for mutton snapper in the U.S. Caribbean. The other is Abril la Sierra in southwestern Puerto Rico (Ojeda-Serrano et al. 2007). Ojeda-Serrano et al. (2007) listed the locations of another 26 potential spawning sites for mutton snapper around Puerto Rico based on interviews with fishers. They recommended that these sites be field verified. Fishers on St. Croix have indicated that there may be a spawning site on the northeast shelf edge based on seasonal catches of mutton snapper in this area and a fisher on St. Thomas has indicated a spawning aggregation on the southern shelf south of St. Thomas/St. John (pers. com.). NOAA National Marine Fisheries Service (NMFS) Southeast Data, Assessment, and Review (SEDAR) 14 Review Workshop (2007) recommended monitoring spawning aggregations for density (abundance indices) and population parameters such as sex ratio and size of fish. Partnership with fishers to conduct research was also strongly endorsed by SEDAR14-SAR2 (2007). USVI fishers have often expressed dissatisfaction with the lack of monitoring of the status of spawning aggregations after seasonal closures have been put in place. Management of species by seasonally closing spawning areas to all fishing and prohibiting possession of a species during spawning periods can have profound socio-economic effects, especially in the short term, because of the high catch per unit effort (CPUE) of high value fish that occurs when 7
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
spawning aggregations are fished. The goal of protecting fish spawning aggregations is to protect reproductive individuals when they are most vulnerable to ensure adequate recruitment to the fishery. Monitoring to determine the effectiveness of regulations will confirm if the goals are being met. This study was conducted to provide information on the status of the Lutjanus analis spawning aggregation on the southwestern insular shelf of St. Croix, U.S. Virgin Islands, verify the spawning period for this species, and provide life history information.
8
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
MATERIALS AND METHODS Fishing Dates and Methods Spawning in Lutjanus analis has been recorded around full moon in the spring and early summer in the Caribbean (CFMC 1993, Claro et al. 2009, Matos-Caraballo et al. 2006). Anon. (2004) recorded spawning of L. analis 4 - 13 days after full moon. In the USVI, fishers targeted spawning aggregations of mutton snapper primarily from March to June (CFMC 1993). Fishing for L. analis in this study was conducted in 2009 around the full moon in April, May, and June inside the MSSCA (Table 1.1) at sites provided by fishers and Carlos Farchette, former VI DPNR Chief of Enforcement (Fig. 1.2). Fishing was conducted from an anchored boat by experienced St. Croix fishermen as well as scientific personnel each fishing day. Fishing commenced at dusk at approximately 18:15h in April, 18:30h in May and 19:00h in June and continued until about half the monthly permitted quota of 30 fish was caught. The number of hours spent fishing varied depending on CPUE. The latest we fished was 23:30h on nights no or few L. analis were caught. Since, only five fish were caught in April, the quota for May was increased to make up for the April shortfall. Table 1.1 Days fished for Lutjanus analis in the Mutton Snapper Seasonal Closed Area in relation to full moon (0 = date of full moon, numbers refer to days before (-) or after full moon). Sampling days are marked with an X and in bold. Day of month 6 7 8 9 10 11 12 13
April Sampling days X X
X
Full moon -3 -2 -1 0 1 2 3 4
May Sampling days
Full moon -3 -2 -1 0 1 2 3 4
X X
June Sampling days
X X X
Full moon -1 0 1 2 3 4 5 6
Fishing was done using hand lines with primarily single J hooks (hook size 7 - 8) and 60 - 200 lb test line. Weights were used only occasionally. Lines were baited with round robin (Decapterus sp.) (Fig. 1.2) and ballyhoo (Hemiramphus brasiliensis). A fluorescent light was attached to the top of the center console to help attract fish and allow fishers to see what they were doing. Chumming with cut up bait (primarily ballyhoo) started shortly before fishing commenced and continued periodically during fishing. Fishing line was paid out into the current until it was near the bottom.
9
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Figure 1.2. Location of fishing sites in the Mutton Snapper Seasonal Closed Area, St. Croix, U.S. Virgin Islands. Garmin MapSource image (top left) blue flags - April 09 sites, black flag, May 09 site, red flags June 09 sites. Google Earth image (top right) - red flags - April 09 sites, yellow flag May 09 site, green flags June 09 sites. MapSource image (left) more detailed view of fishing sites.
10
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Figure 1.2. Gerson Martinez uses a cast net to catch bait fish (left). Some of the baitfish used were caught in shallow water off the south shore of St. Croix prior to fishing (right). Scuba Diving Searches for Lutjanus analis In May and June 2009 and May, June, and July 2010, divers searched for mutton snapper along and adjacent to the insular shelf edge primarily within the MSSCA. In 2010, searches were also conducted to the west of the MSSCA and near the red marker buoy at the southwest corner of the St. Croix shelf commencing mid-afternoon. In May and June 2009, several dives were conducted about an hour prior to fishing from the fishing boat, which was anchored at the fishing site (anchor had retrieval system that allowed the anchor to be recovered by the crown in order to minimize damage to the substrate). In 2010, some dives commenced at sites successfully fished in 2009 and at sites known by local fishers as excellent fishing sites for L. analis. Diver searches were conducted at depths of 20-35m and lasted 50-60 min. Two or three divers spaced about
Figure 1.3. Gerson Martinez (left) and Dr. Norman Quinn (right) searching for mutton snapper spawning aggregation in the MSSCA on the outer shelf. 11
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
7m apart swam at a constant speed and surveyed an area approximately 10m wide while towing a surface buoy (Fig. 1.3). A Garmin GPS map 67Cx on the boat was used to track the divers. Representative dive tracks are shown in Fig. 1.4.
Figure 1.4. Garmin MapSource map showing some of the mutton snapper search tracks within and to the west of the Mutton Snapper Seasonal Closed Area (outlined in green). Fish Abundance Assessment by Fishing Effort Fishing was conducted from an anchored 7m local fishing boat. In May and June, the fishing site was marked each month by a buoy anchored to the bottom and fishing was conducted in the same area each night. The anchor and buoy were removed at the end of fishing each month. To determine fishing effort, the number of lines in the water, start and finish time for fishing and number of individuals of each species of fish caught were recorded for each fishing date. Only mutton snapper were retained in catches for analysis. Biometric Analysis Mutton snapper were purchased from fishers in March and July 2009 and March 2010, before and after the seasonal closure. In 2009, mutton snapper was also caught during the each month of the seasonal closure (April, May and June). Each fish was weighed using a Pesola 5kg 12
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
mechanical scale or an AWS 20kg digital scale. Fork length (FL) was measured using a tape measure or a Picket 76mm plastic fish measuring board. Fish purchased in March 2009 were frozen and analyzed after thawing. Length decreases after freezing. Consequently, the length of frozen fish was adjusted based on the difference in fork length of four fish measured and weighed before and after freezing. Fish caught or purchased after March were not frozen and were analyzed within 24 hours of sampling. Sex Determination Fish were dissected, sex determined and gonads removed, photographed and weighed (Fig. 1.5). Ovaries and representative samples of testes were fixed in 70% isopropyl alcohol or 70% ethanol. If the sex could not be determined macroscopically, gonads were fixed for future microscopic analysis. Fixed gonads were analyzed under a binocular microscope to determine sex. Immature ovaries were distinguished from immature testes by the presence of ovigerous folds with oogonia (visible as small translucent spherules). Early maturing ovaries contained at least a few oocytes including larger translucent (previtellogenic oocytes) and opaque spherules (vitellogenic oocytes). Larger immature ovaries had a visible lumen. Testicular tissue appeared amorphous under the microscope and no lumen was present. No histological analysis was carried out. However, the binocular microscopic analysis of the gonads follows descriptions of histological staging criteria in the literature (Domeier et al. 1996, SEDAR15A-SAR3 2008).
Figure 1.5. Mutton snapper were measured, weighed (Liam Carr), and dissected to remove gonads, stomachs and provide genetic samples. Fecundity and Oocyte Size Distribution Fish purchased from fishers in March 2009 were frozen and then thawed prior to analysis. Fish caught in April, May, June, and July 2009 in the MSSCA were immediately placed on ice after capture (or purchase in July) and processed within 24 hrs. Gonads were removed from both male and female fish and weighed. Two subsamples of each mature female gonad were removed, one from the central portion of each of the paired ovaries. The subsamples were weighed and the gonads and subsamples fixed and stored in 70% isopropyl alcohol for further analysis.
13
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Oocyte Size Distribution The diameter of all eggs (oogonia and oocytes) from at least one subsample per gonad was measured using an ocular micrometer. A minimum of 100 eggs were counted in each subsample. Fecundity All eggs (oocytes) with a diameter of approximately > 0.35mm were counted in all subsamples analyzed. Oocytes > 0.35 mm appeared to be Vtg3 oocytes (large vitellogenic oocytes) and early stages of OM (oocyte maturation showing GVM - germinal vesicle migration) (Brown-Peterson et al. 2009) based on the relative size of oocytes (GVM could not be detected using a binocular microscope). Vtg3 oocytes indicate that the gonad has entered the Spawning Capable phase and are precursors to GVM. Fecundity was estimated using the following equation: Fxy = (GWx/SWxy) x Nxy F = fecundity of ovary x, subsample y; GWx = total weight of gonad x; SWxy = subsample weight of ovary x, subsample y; and Nxy = number of eggs in ovary x, subsample y (modified from Gundersen et al. 1999). The coefficient of variation of representative paired subsamples was calculated to obtain an estimate of variation in the egg counts between subsamples: CV = (std x 100% / F mean)
F mean is the mean fecundity std = standard deviation
Otoliths, Diet, and Genetic Samples Otoliths were removed, dried, placed in labeled envelopes, and stored. Liam Carr, a Ph.D. student at Texas A&M, is currently working with an undergraduate student, Lance Massey, under the supervision of Dr. W. Heyman, analyzing the otoliths (Fig. 1.7) to determine the age of the fish sampled. They prepared an abstract for the 63rd Gulf and Caribbean Fisheries Institute Meeting, November 2010 (abstract provided in Appendix 1), but were unable to complete the analyses in time for the meeting. As of January 11, 2011, they have analyzed 64 of the 156
Figure 1.7. Otoliths were removed by cutting through the head just behind the operculum. The large, paired otoliths are shown in the right photo. 14
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
otoliths. They anticipate completing the otolith analysis by April 30, 2011. They will provide copies of all published papers associated with this grant will be provided to the CFMC and the NOAA Coral Reef Conservation Grant Program. Stomachs were removed, frozen and provided to Dr. Richard Nemeth, University of the Virgin Islands, for his research on fish diets. He will provide copies to the CFMC of any published papers related to this data. Tissue samples of L. analis were provided to Hector Rivera (St. Croix) who was collecting samples for Dr. John R. Gold, Texas A&M University and to Dr. Gold via Dr. Nemeth for his studies of L. analis population structure and phylogenetics. Dr. Gold is finalizing a manuscript describing genetic variation among populations of L. analis from St. Croix, St. Thomas, the east and west coasts of Puerto Rico, and the Florida Keys (Carson et al. ms). A draft was provided for review in January 2011. The manuscript is not yet finalized. Results suggest that L. analis can be subdivided into a number of demographic stocks similar to L. griseus (Gold et al. 2009), L. synagris (Gold et al. ms, Karlsson et al 2009), and L. campechanus (Saillant et al. 2010).
15
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
RESULTS Catch Results in the Mutton Snapper Seasonal Closed Area Fifteen species of fish were caught within the Mutton Snapper Seasonal Closed Area (MSSCA) (Table 1.2) during three fishing trips in April ((48 fishing hrs) (fishing hrs = hrs fished x number of fishers)), two in May (11 fishing hrs), and three in June (13.75 fishing hrs) 2009. Only three species were caught in all three months: Lutjanus analis (mutton snapper), Ocyurus chrysurus (yellowtail snapper), and Carnax latus (horse-eye jack). Four species of snapper were caught (Table 1.2) but only L. analis and O. chrysurus were caught in large numbers. The fishing technique used was one commonly used in the US Virgin Islands to target mutton snapper and yellowtail snapper, and these were the species that were the most abundant in the catches. The catch rate for mutton snapper in the MSSCA was highest in May and June (Table 1.2, Fig. 1.8). In April, fishing was done on three nights, two nights before the full moon and one night after the full moon (Table 1.1). Only five mutton snapper were caught in April, and only on fishing nights before the full moon. Four of the five fish caught were mature and one was maturing. No fish were caught four days after full moon in April, even though 13 mutton snapper were caught in less than three hours on the 4th day after full moon in June. All sites fished were within the outer portion of the MSSCA. The sites fished in April were different from the sites fished in May and June (Fig. 1.2), which may have affected catch success. In the latter months, the sites fished were adjacent to a “bridge” connecting two reefs separated by a sand channel. “Bridges” are known by fishers to concentrate fish migrating from shallow to deepwater and vice versa. In July, Gerson Martinez (pers. com.), fished within the MSSCA but was unable to fish the location we had fished in May and June because it was occupied by another fisher. He did not catch any mutton snapper and it is unknown if the fisher occupying the May/June fishing location caught any mutton snapper. Mutton snapper catch per unit effort (CPUE), based on number of individuals caught, was highest in May and June (Fig. 1.8). Mutton snapper CPUE in May was more than twice that of June and 50 times that of April. The seasonal CPUE for mutton snapper, based on weight, was similar to CPUE, based on numbers: April CPUE = 0.41kg, May CPUE = 13.27kg, and June = 5.78kg. In contrast, yellowtail snapper catches exceeded mutton snapper catches in April 2009, but declined by two-thirds in May and June 2009 (Table 1.2). The total CPUE, based on number of individuals, for species other than mutton snapper, was similar in all months. Total CPUE, including mutton snapper, increased by 600% May and 300% June compared to April because of the high catches of mutton snapper (Table 1.2). The fishing gear used did not target bottom dwelling fish. However, a few individuals of three species of serranids and a holocentrid (Holocentrus sp.) were caught (Table 1.2). The serranids caught were the smaller species commonly targeted by fishers on St. Croix. All the species in the catches, except the reef shark (Carcharhinus perezii), were recorded in the fish surveys in this study (Chapter 3). The maximum size of male mutton snappers exceeded female mutton snapper caught in the MSSCA between April and June 2009 (male = 660 mm (25.98in), 5.73kg (12.63lb); female = 16
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
635mm (25in.), 5.0kg (11.02lb)). The mean weight of all mutton snapper caught in the MSSCA in April, May and June 2009 was 2.49 kg or 5.49 lbs (N=94, SE = 1.23). The average weight of female fish (N = 29, 3.094 kg or 6.82 lbs) was significantly larger than males (N = 65, 2.218 kg or 4.89 lbs ) (MS Excel T-test assuming unequal variances = 3.42, df = 52, P = >0.001). Weight of fish caught in May and June 2009 was compared for each sex separately. There was no difference in the weight of either male or female fish between months (Female: T-test = 0.41, df = 19, P one tail =0.344); Male: T-test = -1.5, df = 24, P = >0.07).
7
CPUE (No. fish caught/fisher/hr)
6 5 4
Max Min
3
Mean 2 1 0 April All Fish
April MS
May All Fish
May MS
June All Fish
June MS
Figure 1.8. Mean CPUE (catch per unit effort based on number of fish caught fisher-1 hr-1) for all fish and Lutjanus analis (MS) caught in the Mutton Snapper Seasonal Closed Area in 2009 during the three months of the seasonal closure. Number of fishing days/fish caught per month: April = 3 days/5 fish, May = 2/59, June = 3/31. Black bars indicate maximum and minimum CPUE on different fishing days.
17
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Table 1.2. Summary of the number and CPUE (number of fish caught per fisher per hour fishing) of fish caught in the Mutton Snapper Seasonal Closed Area in the spring of 2009.
Family Balistidae Belonidae Carangidae Carcharhinidae Echeneidae Holocentridae Lutjanidae
Muraenidae Rhincodontidae Serranidae
Sphyraenidae
Species Balistes vetula
Common Name Queen triggerfish Needlefish Caranax latus Horse-eye jack Carcharhinus perezii Reef shark Echeneis sp. Remora Holocentrus sp. Squirrelfish Lutjanus analis Mutton snapper Schoolmaster Lutjanus apodus snapper Lutjanus jocu Dog snapper Ocyurus chrysurus Yellowtail snapper Gymnothorax moringa Spotted moray Ginglymostoma cirratum Nurse shark Cephalopholis cruentatus Graysby Cephalopholis fulvus Coney Epinephelus guttatus Red hind Sphyraena barracuda Barracuda Total including mutton snapper Total excluding mutton snapper
No. fish 0 0 4 1 0 1 5
18
1 1 31 0 0 0 1 0 0 45 40
Number of fish caught each month in 2009 April May June No. fish No. fish No. fish caught per caught per caught per fisher per No. fisher per No. fisher per fishing hr fish fishing hr fish fishing hr 0.00 1 0.09 0 0.00 0.00 1 0.09 0 0.00 0.08 2 0.18 1 0.07 0.02 0 0.00 0 0.00 0.00 0 0.00 1 0.07 0.02 0 0.00 0 0.00 0.10 56 5.09 31 2.25 0.02 0.02 0.65 0.00 0.00 0.00 0.02 0.00 0.00 0.94 0.83
0 1 3 0 0 0 0 1 0 65 9
0.00 0.09 0.27 0.00 0.00 0.00 0.00 0.09 0.00 5.91 0.82
0 0 3 2 1 1 0 1 1 42 11
0.00 0.00 0.22 0.15 0.07 0.07 0.00 0.07 0.07 3.05 0.80
Total no. fish 1 1 7 1 1 1 92 1 2 37 2 1 1 1 2 1 152 60
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Red Buoy Site Several dives were conducted at a reef 1km southwest of the red buoy marking the St. Croix shelf edge for shipping. The reef lies in territorial waters. During four dives on 2 May 2010 (4 days after full moon), large schools of Lutjanus cyanopterus (cubera snapper) (Fig. 1.9), Chaetodipterus faber (Atlantic spadefish) (Fig. 1.10), Trachinotus falcatus (permit), Caranx crysos (blue runner), and a smaller school of crevalle jack (Caranx hippos) (Fig. 1.11) were observed and photographed. On the last dive, about an hour before dusk, about 200 Lutjanus analis (mutton snapper) were observed by Gerson Martinez forming an aggregation over sand adjacent to the reef; no spawning was observed. Because of the low light levels, depth and distance the fish were from the divers, they were not able to be photographed. On two dives conducted on 29 May 2010 (2 days after full moon), only one large school of fish (>50 fish), Aluterus schoepli (orange filefish), was observed on the reef.
Figure 1.9. Large school of cubera snapper (Lutjanus cyanopterus) at Nicky's reef, St. Croix.
19
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Figure 1.10. School of Atlantic spadefish (Chaetodipterus faber) hovering in water column at Nicky's reef, St. Croix.
Figure 1.11. Schools of fish and conch at Nicky's reef near the Red Buoy. Starting top left moving clockwise: queen conch (Strombus gigas) amassing at the foot of the reef at a depth of 45m, permit (Trachinotus falcatus) showing black spot spawning coloration (Anon. 2004), blue runner (Caranx crysos), crevalle jack (Caranx hippos), and blue runner (Caranx crysos). 20
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Reproductive Aspects Sex Ratio Lutjanus analis are gonochoric based on the parameters provided for describing L. griseus a gonochoric species by Domeier et al. (1996): the similarity in the size of males and females at sexual maturation, the overlap in size frequency distribution of the sexes, and the absence of any evidence of sexual transition. Males were over twice as abundant as females (Table 1.2) in May and June 2009 catches in the MSSCA. In April, females were more abundant than males but the sample size was small.
Table 1.2 Ratio of number of male to number of female Lutjanus analis caught in Mutton Snapper Seasonal Closed Area during the area and seasonal closures in 2009. Month April May June Total
Male 2 43 21* 66
Female 3 16 10 29
Sex Ratio 0.7 2.7 2.0 2.3
*One fish was bitten in half during capture on hook and line, but the testes were still attached.
Gonad Somatic Index The gonad somatic index (GSI - gonad weight (g)*100/weight of fish (g)) for L. analis was determined for fish purchased in March 2009 and 2010 and July 2009 and for fish caught in the MSSCA in April, May and June. The maximum GSI for all females sampled was 5.61 (caught 9 June 2009) and males 5.49 (caught 12 May 2009). The highest GSI values were in April, May and June for both sexes (Table 1.3, Fig. 1.12). GSI was lower and more variable in July (fish were purchased from fishers and not caught in the MSSCA). This was the only month in which a female was found with a spent gonad. This female was sampled on July 18 which was 11 days after full moon. GSI for females was lowest in March 2009 and 2010 when the proportion of small fish was higher. Male GSI was very low in March 2009 with the two largest males purchased (462mm and 475mm FL) having a GSI of 0.10 and 0.27, respectively. Even the one large female purchased (599mm FL) had a GSI of only 0.42. Female GSI and FL was smaller in 2010 compared to 2009 although the GSI was similar. A much larger number and size range of males was sampled in 2010 (N = 14, 513 - 598mm FL) with a GSI range of 0.13 (513mm FL) 2.08 (542mm FL). The difference in GSI between years for males was likely a function of the proportionally larger sample size in March 2010 (Table 1.3), since the mean number of days before the April 9, 2009 / March 30, 2010 full moons that fish were sampled was greater in 2010 (-18 days) than in 2009 (-4 days).
21
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Table 1.3 The monthly mean GSI and standard error (SE) for males (♂) and females (♀) and mean fork length (FL) (mm) and range of FL of Lutjanus analis. April to June fish were caught in the MSSCA. March and July fish were purchased from fishers and smaller fish were targeted. March ‘09
April ‘09
May ‘09
June ‘09
July ‘09
March ‘10
♀
♂
♀
♂
♀
♂
♀
♂
♀
♂
♀
♂
N GSI (SE)
2 0.28 (0.14)
4 0.12 (0.05)
3 2.94 (0.46)
2 2.14 (1.86)
16 3.04 (0.22)
43 2.86 (0.21)
10 3.12 (0.37)
20 2.98 (0.30)
4 1.82 (0.75)
3 0.93 (0.24)
5 0.47 0.13
14 1.38 0.23
FL (range)
493 (386599)
427 (369475)
615 (590 635)
555 (490620)
539 (410 633)
472 (367 600)
525 (393625)
503 (375660)
601.5 (550 653)
628 (605644)
453 (340513)
497 (373598)
Figure 1.12. Lutjanus analis - Mean gonad somatic index (GSI) (gonad weight (g)*100/weight of fish (g)) with Standard Error bars. See Table 1.3 for the number of fish sampled on each date. The size range (FL) of all reproductive females sampled was 393 - 635 mm. A linear regression of GSI versus FL for females caught April - June 2009 explained only .09% of the variance in GSI (Fig. 1.13). There was no significant difference in GSI versus fork length (P = 0.879), indicating that the amount of energy an individual fish expended on gonad production does not increase or decrease with fork length, within the size range sampled.
22
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
6
y = -0.0004x + 3.2652 R² = 0.0009
5 GSI
4 3 2 1 0 300
400
500
600
700
Fork Length (mm) Figure 1.13. Lutjanus analis ♀: Linear regression of GSI based on fork length (N = 29). The size range (FL) of all reproductive males sampled was 367 - 660 mm (GSI 2.25 and 2.11, respectively). A linear regression of GSI versus FL for males caught April - June 2009 explained only 4% of the variance in GSI (Fig. 1.14). There was no significant difference in GSI versus FL (P = 0.103). 7 y = 0.0036x + 1.118 R² = 0.0416
6
GSI
5 4 3 2 1 0 300
400
500
600
700
Fork Length (mm) Figure 1.14. Lutjanus analis ♂: Linear regression of GSI based on fork length (N = 65). Size at the Onset of Reproduction Fish caught in April through June 2009 ranged in size (FL) from 367 - 660mm: mean size of males was 484mm FL (range 367 to 660mm, N = 65) and females 542mm FL (range 393 to 653mm, N = 29). Although more than twice as many males were caught as females, a size frequency analysis of female and male fork length shows that proportionally more large female 23
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
fish were caught than large males fish (Figs. 1.15). Though the actual number of large fish (>525 mm FL) was similar for both males and females, 20 and 19 respectively. 7 6 6 5
No. of Fish
5 4 4 3
3
3 2
2
2 1
1
1
1
0
0
0
325
350
375
1 0
0 700
675
650
625
600
575
550
525
500
475
450
425
400
0
Female Fork Length (mm) a 14
13
No. of Fish
12 10
9 8
8
8 6
5 4
4
3
4 3
2
4 3
0
325
350
1 0
1 0 700
675
650
625
600
575
550
525
500
475
450
425
400
375
0
Male Fork Length (mm)
Figure 1.15 Length frequency of analysis of female (a) and male (b) mutton snapper (Lutjanus analis) caught in the Mutton Snapper Seasonal Closed Area in April, May and June 2009. The smallest mature or maturing fish sampled was 393mm FL for females (caught 11 Jun 09, GSI 1.96) and 410mm FL (caught 12 May 09, GSI 3.7). For males the smallest mature or maturing fish was 367mm FL (caught 11 May 09, GSI 2.25). Ten male fish <410 FL were
24
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
caught in May and June 2009. Nine of these ten fish were mature or maturing and had GSI values ranging from 1.49 - 5.45; one (caught 11 June 09, FL 392mm) was immature (GSI 0.22). Because of the relatively small sample size, data from males and females were combined to determine the length at first maturity, which "is conventionally the size at which 50% of the population attains an advanced stage of gonad development (Lm50%)" (Ungaro 2008). Size at Lm50 was approximately 390mm (Fig. 1.16). Given the small sample size and variation in maturity with size, the 95% confidence limit for the size at first maturity was large (330 - 410mm), particularly for the lower bound.
Figure 1.16. Estimated size of first maturity of mutton snapper (Lutjanus analis) using logistic regression (N = 129) based on all fish caught (male and female) in the MSSCA and purchased from fishers on St. Croix in 2009 and 2010. Length Weight Relationship The length weight relationship for male and female Lutjanus analis collected between 24 March 2009 and 20 March 2010 was calculated using a power regression (Fig. 1.17) (P<0.001). The equations for males and females differ only slightly and explain almost 98% of the variation.
25
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Figure 1.17. Length weight relationship for male (open squares, black line) and female (black diamonds, dashed line) Lutjanus analis. N: ♀ = 41, ♂ = 85. Fecundity and Egg Size Distribution Based on the egg size distribution in gonads from fish sampled from March to July 2009 (Fig. 1.18 and 1.19), mutton snapper: 1. Are batch spawners - eggs are released in batches over a period of days or months with only a portion of yolked oocytes spawned in each batch (Murua and Saborido-Rey 2003), 2. Possibly have indeterminate fecundity - number of eggs produced in a spawning season is not fixed before the onset of spawning - unyolked eggs continue to mature and be spawned during the spawning season (Murua and Saborido-Rey 2003) 3. Have asynchronous oocyte development - oocytes present in all stages of development without dominant populations (Murua and Saborido-Rey 2003), producing successive batches of oocytes multiple times during the spawning season.
26
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
Figure 1.18. Sample from an ovary of a Lutjanus analis caught 11 May 2009 showing size range of eggs. The Largest eggs are approximately 0.5 mm diameter. The small eggs, part of the oogonia net, range in size from 0.06 - 0.1 mm. Egg size distribution changed over time (Fig. 1.19). In March 2009, the largest, most developed egg sizes were absent, while they were present in May, June and July 2009. Eggs measured from fish caught in the first week of July, had an almost even distribution of egg sizes compared to March, May and June when the majority of gonads were small. The one female fish sampled on July 18th, 11 days after full moon, had few large eggs and the ovary was flaccid (spent) (Fig. 1.19). Fecundity increases with increasing female size. MS Office Excel 2007 was used to fit linear trendlines to the data with R2 values >70% (Fig. 1.20).
27
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
11 May 09 (13-1)
60
60 No. of eggs
No. of eggs
27 March 09 (5-1) 40 20 0
40 20 0
Egg size (mm)
Egg Size (mm)
9 June 09 (83b)
12 June 09 (102a) No. of eggs
80 60 40 20 0
200 150 100 50 0
Egg size (mm)
Egg size (mm)
8 July 09 (104b)
18 July 09 (106b)
No. of eggs
No. of eggs
No. of eggs
0.1 0.2 0.3 0.4 0.5 0.6
45 40 35 30 25 20 15 10 5 0
350 300 250 200 150 100 50 0
Egg size (mm) Egg size (mm)
Figure 1.19. Egg size distribution from subsamples (sample # in parentheses) of representative ovaries of Lutjanus analis from 27 March to 18 July 2009 showing asynchronous oocyte development over time.
28
Chapter 1: Mutton Snapper (Lutjanus analis) Spawning Aggregation
3,500,000
3,000,000
Number of Eggs
2,500,000
May y = 8248.6x - 3E+06 R² = 0.6955
2,000,000
May-09 June y = 5114.2x - 2E+06 R² = 0.7493
1,500,000
Mar-09 Jun-09 Jul-09 Linear (May-09) Linear (Jun-09)
1,000,000
500,000
0
300
400
500
600
700
Fork Length (mm) Figure 1.20. Fecundity of Lutjanus analis by fork length by month. Linear trend lines, the equation for the trend lines, and R2 values are shown for May and June 2009. There were insufficient data for trendlines for March 2009 and July 09. No mature females were sampled in March 2010.
29
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
DISCUSSION The MSSCA (Mutton Snapper Seasonal Closed Area) has been under territorial and federal government management since 1993/1994. In 2003, CRCP funds were used to obtain high resolution bathymetry and map the habitat of the MSSCA (Geophysics GPR International, Inc. 2003, Prada 2003) in order to describe the habitat within the protected area and identify geomorphological features that may attract the mutton snapper spawning aggregation. In 2009, funding was provided by the CRCP to the CFMC to carry out this study, which was the first attempt to determine the location of the mutton snapper (Lutjanus analis) spawning aggregation in the MSSCA and to verify the continued existence and status of the aggregation. Historically, the mutton snapper spawning aggregation in the southwest of St. Croix has been targeted by fishers. With the implementation of the MSSCA in 1994 and the seasonal prohibition on landing mutton snapper in 2006, fishing on this spawning aggregation has ceased. While fishers on St. Croix understand the need for protecting fish spawning aggregations, they have expressed concern about the loss of income from the seasonal prohibition on fishing for mutton snapper and the prohibition of fishing in the MSSCA. Fishing on aggregations is highly lucrative. A local high-liner (pers. com.) related that he had caught 103 mutton snapper in just one night of fishing on the aggregation (his personal best). At an average size of about 5.5lbs (based on mean weight of May 2009 catch in this study), his estimated total catch was 567lb. Assuming a price of $6 per lb (low end of the price range for snapper), the fisher could have made $3,400 from just one night of fishing. Given that he likely fished the aggregation more than one night in a month and more than one month in a year, a significant portion of his annual income may have been derived from fishing the aggregation. Given the income loss to fishers on St. Croix, especially after implementation of the seasonal closure in 2006, it was important to obtain information on the status of the aggregation and on life history parameters of mutton snapper that used in stock assessments, status determinations, and assessing the vulnerability of the species to fishing pressure. Spawning Season Mutton snapper spawning has been recorded from February to September in the Caribbean (Table 1.4). Spawning months vary with location. They also vary annually depending on when full moon falls in the month. For example, the peak spawning period was May and June in Cuba (Paris et al. 2005, Claro et al. 2009), March to May in Puerto Rico (Ojeda-Serrano et al. 2007), March through May if the full moon falls after the middle of the month and April to June if the full moon falls before the middle of the month in Belize (Graham et al. 2008), and May and June on St. Croix, USVI (this study). While fish were not sampled in August or September (months spawning was recorded in Cuba), it is unlikely that they spawn in these months on St. Croix. The declining GSI in males and females in July (Figure 1.11 and Table 1.3) and the occurrence of a spent ovary in a female purchased from a fisher on July 18, 2009, 11 days after full moon, suggested that the annual spawning cycle was at or near its end in July in St. Croix. The reported spawning days in relation to lunar phase varies greatly (Table 1.5). Some of the variation depends on when fishing occurs and/or gonads are macroscopically determined to be ripe. For example, Graham et al. (2008) reported fishing for mutton snapper in Belize occurred 30
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
over 10-16 days before and after full moon while Claro and Lindeman (2003) reported fishing from two to three days before full moon to the three-quarter lunar phase. In this study high CPUE of reproductively mature fish occurred from 2 - 5 days after the full moon (Table 1.5). These were the only days we fished during the peak spawning months of May and June, so it is likely that high catches could have occurred both earlier and later in the lunar phase. Table 1.4: Representative studies showing the geographic variation in the months with documented spawning (macroscopic gonad observations, gonad somatic index (GSI), microscopic and histological analyses, field spawning observations, fisher interviews) of Lutjanus analis in the Caribbean and Florida. Months with documented spawning are shown with an x. "X's" in bold and capitals indicate peak spawning months. Location Cuba1 Cuba2 Puerto Rico3 Puerto Rico4 LaParguera, PR5 Belize6 Gladden Spit, Belize7 Gladden Spit, Belize8 US Caribbean9 Tequesta, Florida10 Florida Keys10 Florida11 NE Caribbean12 St. Croix, VI13
Feb
March x
X x
x
X x x X
x x
April x x x X X X X X X x x x x
May X X x X
June X X x x
July x x
X X X X X X X x X
X x X x X X X x X
x x
August x x
Sept x
x
x x x
1
Claro et al. (2001) and Claro et al. (2009) Claro et al. (2003). Summary of all sites - spawning months varied among sites 3 Matos-Caraballo et al. (2006) 4 Ojeda-Serrano et al. (2007) - based on fisher interviews 5 Esteves-Amador (2005) - only monitored fisher catches of mutton snapper in April 2003 6 Heyman and Kjerfve (2008) spawning months based on direct visual observations by divers of spawning and inferences from a variety of indirect evidence 7 Anon. (2004) 8 Graham et al. (2008) based on Table 2 in publication - peak months varied among years with timing of full moon. Peak spawning occurring in only two of the three months marked in any year. 9 CFMC and NOAA (2005) 10 SEDAR15A-SAR3 (2008) - authors inferred spawning months from GSI and histological analysis of gonad maturity stages 11 Burton (2002) cited in SEDAR15A-SAR3 (2008) inferred from GSI 12 Erdman 1976 13 This study 2
Claro and Lindeman (2003) reported that snappers appeared to be batch spawners, with individual females releasing several egg batches over a 5 to 10 day period during only one month. They designate mutton snapper as Type A species vs Type D species. Oocytes of Type A species mature at different rates while all oocytes of Type D species "mature at once but 31
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
ovulate at different rates" (p. 102) (Claro and Lindeman 2003). The results of study support the designation of mutton snapper as a Type D species, however, see the discussion on fecundity below. Table 1.5: Days spawning documented for mutton snapper (Lutjanus analis) in relation to lunar phase. Nf = no fishing due to bad weather. Capitalized x's indicate reports of peak spawning/ catch periods. Location -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 LaParguera, PR1 (April x Nf Nf Nf Nf x x X x x 2003) Gladden Spit, x x x x x x x x x x Belize2 Gladden Spit, x x x x x x x x x x 3 Belize Cuba4 x x x x x x x x x x x Not X X reported5 6 Cuba x x x x x x x x x x x St. Croix, USVI (April, May x x X X X X and June 2009)7,8 1 Esteves-Amador (2005) based on commercial fish catches 2 Anon. (2004) 3 Heyman and Kjerfve (2008) 4 Claro (1981) cited in Esteves-Amador (2005) 5 Garcia-Cagide et al. (2001) cited in SEDAR15A-SAR3 (2008) 6 Claro and Lindeman (2003) 7 Based on catches in MSSCA. Fishing was not conducted more than five days after the full moon because the permitted catch limit in the MSSCA was always reached by then. 8 April was the only month that we fished for mutton snapper on days prior to the full moon. Three days before full moon only one mutton snapper caught (mature female) and 11 yellowtail snapper. Two days before full moon four mutton snapper (one maturing male and three mature females) and 9 yellowtail snapper caught. Four days after full moon in April no mutton snapper and nine yellowtail snapper caught. Four of five fish caught had mature gonads.
Spawning Aggregation Location Domeier et al. (1996) and Heyman and Kjerfve (2008) reported that mutton snapper were shelfbreak spawners. Heyman and Kjerfve (2008) observed mutton snapper aggregating at a depth of 32 - 37m at the shelf edge of Gladding Spit, Belize and releasing gametes 23-25m below the surface. Divers observed actual spawning of mutton snapper four times between May and August between 13:00 - 16:30, 3 to 8 days after full moon (Heyman and Kjerfve 2008). 32
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Within the MSSCA, we did not observe any spawning behavior or increase in mutton snapper abundance while diving during the spawning season. We conducted searches from midafternoon to dusk after full moon during April, May, June and July in 2009 and 2010 on both the shelf edge and on both sides of the sand channel immediately north of the shelf-edge reef. Dives were conducted at depths of 20 - 34 m. We also conducted a number of dives while anchored at fishing sites. At the fishing sites we dived from the anchored boat in the late afternoon just prior to dusk and just prior to putting fishing lines in the water. We were surprised to encounter so few mutton snapper on dives in general, but especially on dives conducted at fishing sites. Typically, less than 30 minutes after divers climbed in the boat in May and June 2009 mutton snapper were rapidly caught by fishers. In one instance, fishers started chumming while divers were in the water, but divers did not see any mutton snapper. Dives were done as unobtrusively as possible with only 2-3 divers in the water at one time. Possibly, fish were attracted to the chum and light on the boat while migrating to or from a spawning aggregation in deeper water than divers could observe (depth range of mutton snapper is 5 - 86m in Puerto Rico (Esteves-Amador 2005) with the greatest depth of 151m reported by Roe (1975) cited in SEDAR14-SAR2 (2007) in the Carolinas) or to a site outside the MSSCA. Weber and Brown (2008a, b) conducted a six-year study of spawning aggregations at sites around St. Croix with the assistance of local fishermen. They dived a number of sites within and to the west of the MSSCA around full moon during peak spawning months of the mutton snapper: April and May 2005. They also dived this area in January 2003, February 2004, and March 2003 and 2005 before, during and after full moon. Despite conducting dives during the spawning months for mutton snapper, the only aggregation of mutton snapper that they found was at a single site in the southwest corner of the St. Croix shelf, west of the MSSCA. They labeled this a schooling only aggregation, not a spawning aggregation. They did not document spawning aggregations or schools of mutton snapper at any of 73 sites surveyed around St. Croix. The most likely location of the spawning aggregation in the area of the MSSCA is the SW corner of St. Croix. This corner has geomorphological characteristics of mutton snapper spawning sites at other locations, i.e. a promontory close to a sharp bend in the shelf (Anon. 2004). In contrast, the shelf edge of the MSSCA has no promontory nor is it near a sharp bend in the shelf. The shelf edge is characterized by a fairly straight line of spur and groove reefs without an obvious promontory/projection (Quinn and Kojis 2010, Chapter 2 of this study) that characterizes many aggregation sites in the Atlantic (Anon. 2004). If mutton snapper do not aggregate to spawn in the MSSCA, but near the Red Buoy Reef, then mutton snapper appear to be vulnerable to fishing several km from an aggregation site based on our high catch rates within the MSSCA. Status of the Mutton Snapper Aggregation While no aggregation was detected in the MSSCA on St. Croix during dives conducted in 2009 and 2010, the high CPUE of mutton snapper in May and June 2009 and the high GSI values from 33
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
March through July indicated that mutton snapper still aggregate to spawn within or in the vicinity of the MSSCA and, based on the CPUE (number of fish caught fisher-1 hr-1), likely do so, in fairly large numbers. A comparison of the CPUE (weight based, kg fisher-1 hr-1) in the peak spawning months of May and June between Gladden Spit and this study, indicates that the St. Croix aggregation is relatively healthy. The average monthly CPUE at Gladden Spit ranged from 2.4 -5.2kg fisher-1 hr-1, while the CPUE in this study ranged from 10.1 - 14.4kg fisher-1 hr-1. However, differences in fishing need to be taken into account. Graham (pers. com.) noted that fishers at Gladden Spit fish during the day. She thought that this may affect the CPUE because mutton snapper spawn in mid-afternoon and may not take the hook when they are spawning. She thought that they may bite better at dusk and night when we fished (this study). Also, Graham et al. (2009) included changing of fishing stations, baiting time (not including bait search), and travel and anchoring time in hrs fished, though travel time was short. Of these items, only baiting time was included in the CPUE calculations for this study. The mean fishing time at Gladden Spit ranged from 12.4 to 17.8 hrs day-1 compared to 1.5 to 2 hrs day-1 in this study. Graham et al. (2008) included the majority of fishing effort at Gladden Spit in their mean CPUE. Our CPUE was limited to our efforts with no competition from other fishers and we fished for a limited period of time, stopping once our quota was reached. Since the implementation of the seasonal possession prohibition, it appears fishing pressure on mutton snapper during the spawning season and on the aggregation in the vicinity of the MSSCA has been curtailed. We saw no other boats fishing at night in the vicinity of the MSSCA on the nights that we fished for mutton snapper in 2009. Nor did we see fishing vessels in the southwest corner of the shelf in 2010 when we carried out diver searches for mutton snapper in the mid-afternoon to early evening after the full moon in May, June and July. In July 2010, no mutton snapper were present at the LaReine fish market. Fishers stated in July that they forgot about fishing for mutton snapper and, even though snappers may aggregate to spawn in July, fishers likely have not traditionally targeted the aggregation and continue not to do so during this month. Fishers may not target the aggregation in July because mutton snapper may only aggregate in July in significant numbers when the full moon falls in the late in the last lunar quarter of June or in the first quarter of July. Thus, fishing success in July may be highly variable among years. Also, July may be last month spawning occurs and the number of fish spawning may be too few to make it worth their while. If individual mutton snapper spawn throughout the spawning season, then, in the past, fishing at the earlier in the spawning season may have significantly reduced the number of fish and, in combination with July being the end of the spawning season, may have resulted in a low CPUE. Size at Onset of Reproduction Thompson and Munro (1983) suggested, based on length distributions of catches, that most lutjanids exhibit sexually dimorphic growth rates and sizes at maturity. However, their data were limited or inconclusive for most lutjanid species. A number of studies have since confirmed that female mutton snapper mature at a larger size than males (Table 1.6, this study). The mean size of female mutton snapper in catches were significantly larger than males at Gladden Spit, Belize (female mean FL - 554mm, male mean FL = 523mm) (Graham et al. 2008) and St. Croix (female mean FL - 542mm, male mean FL = 484mm) (this study). Peak female fork length 34
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
frequency distribution of fish caught during the period of the mutton snapper spawning aggregation were similar at both Gladden Spit, Belize (560-650mm FL) (Graham et al. 2008) and St. Croix (575-650mm FL). Maximum size however was larger at Gladden Spit (910mm FL) than this study (635mm FL). The peak size frequency distribution of males occurred at a larger size at Gladden Spit than in this study (510-600mm FL and 425-500mm FL, respectively). In both studies, males represented both the maximum and minimum sizes recorded in fish spawning aggregation catches: Gladden Spit - 180 - 960mm FL, this study - 367 - 660mm FL. There could be a several of reasons for the smaller maximum and mean size of females and males on St. Croix compared to Gladden Spit. The smaller number of fish sampled in this study (n = 65) compared to Graham et al.'s (2008) study( n = 4,096) reduced the chance of catching very large fish on St. Croix and the catch may not accurately represent the size frequency distribution on St. Croix. However, mutton snapper in the St. Croix aggregation may be smaller on St. Croix because of intense fishing pressure on the population throughout the year and historical fishing on the aggregation itself. Fishing on the aggregation was not fully curtailed until 2006 when the seasonal prohibition on possession went into effect. It is also possible, given St. Croix's relative isolation from other insular shelves, that the smaller size of mutton snapper on St. Croix may be a characteristic of the population, especially if there is evidence that it is genetically distinct (Carson et al. ms). Size and age at maturity of mutton snapper has been estimated at a number of locations (Table 1.6) Female size at maturity (Lm50) ranges from 353mm TLmax (maximum total length) for females in Florida to 574mm TL (total length) in Cuba (Table 1.6). Figuerola and Torres (2001) reported that all males and females mature at 43.1 cm and 45cm FL, respectively. There may be a number of reasons for the differences in size at Lm50 at different locations: 1) population (genetic) differences at different geographic locations, 2) more rapid growth rates in warmer water and/or where food abundant resulting in larger size at Lm50 (although it appears from Table 1.6 that in all locations age increases concomitant with size at Lm50), 3) differences in methodology in determining maturity, e.g. histologic vs microscopic vs. macroscopic methods, and 4) greater fishing pressure at some locations resulting in selection that results in fish reproducing at smaller sizes. Maximum Length and Age Maximum length of mutton snapper in the US Caribbean varied between years and location, ranging from 540 to 790mm FL between the years 1983 and 2006 in Puerto Rico and 460 to 780mm FL in the US Virgin Islands (SEDAR14-SAR2 2007). The maximum length of mutton snapper caught in this study was 660mm FL. The only age-length study done in the US Caribbean was in Puerto Rico by Figuerola and Torres (2001). They determined that the maximum age of the mutton snapper to be 17 years. Mason and Manooch (1985) reported a maximum age of 14 yrs based on a 824mm TL fish from the east coast of Florida. Other studies in Florida, reported that mutton snapper live much longer. Burton (2002 cited by SEDAR14-SAR2 2007) and SEDAR15A-SAR3 (2008) reported a 35
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
maximum age of 29 yrs in south of Fort Pierce, Florida, and 40 years in Tequesta and Marathon, Florida, respectively. Table 1.6: Mutton snapper (Lutjanus analis) size and age at maturity various locations. FL = fork length. TL = total length. Male/Female combined Location
Lm50 (mm)
Age (yr)
Puerto Rico1
330 FL
Cuba2 Florida (Tequesta and Marathon, Florida Keys3 Unidentified location4 Cuba SW, NW
Male Lm50 (mm)
~500 FL
5
530 FL
500 FL
Unidentified location6 Hatchery stock obtained in Florida7 St. Croix, US Virgin Islands
~5
Female Age (yr)
Lm50 (mm)
Age (yr)
414 FL ca. 459 TLmax 545 FL 353 TLmax
2.07
402 TL 520 FL ca. 574 TLmax
3.71 5.5
402 SL 375-465 TL
3 8
450-470 TL
~390 FL (range ca. 330 - 410 mm)
1
Figuerola and Torres (2001) Claro et al. (2001) 3 SEDAR 15A SAR3 (2008) 4 SEDAR15A-SAR3 (2008) 5 Claro and Lindeman (1981) cited in Froese and Pauly (2007) 6 SEDAR14-SAR2 (2007) - Rojas (1960 cited by Druzhinin 1970) 7 Watanabe 2001 8 This study 2
Sex Ratio The male:female sex ratio of mutton snapper in catches from Gladden Spit was nearly equal (1:1.2), while in St. Croix males caught in the MSSCA were more than twice as abundant as females (2.3:1). This may be a function of the high fishing pressure on the St. Croix spawning aggregation in the recent past. Absolute numbers of male and female fish of larger sizes >525mm were similar on St. Croix (20 males to 22 females, sex ratio = 1:1.1). Since females mature at a larger size than males, smaller females may be as abundant as smaller males on St. Croix, but may not yet have recruited to the spawning aggregation. Fishing pressure on the spawning aggregation and on this species throughout the USVI has been reduced since 2006. We hypothesize that female fish will recruit to the spawning aggregation in future years and the sex ratio will equilibrate. Fecundity Individual female mutton snapper produce large numbers of eggs (Table 1.7). Watanabe (2001) reported that fecundity values range from 186,500 to 603,00 eggs kg-1 for fish 2.3-2.27kg, respectively. Wild caught fish (this study) in the same size range had estimated fecundity values 36
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
ranging from 500,425 eggs kg-1 (2.19kg fish) to 496,345 eggs kg-1 (2.82kg). The largest number of eggs kg-1 in this study was 648,972 eggs in a 4.54kg fish caught on May 11 2009. Watanabe (2001) observed one egg size group (mean egg diameter = 0.382 mm, range = 225 475 mm FL) in an ovarian biopsy of a 3yr old hatchery reared female (460mm FL) and suggested that the unimodal egg distribution indicated that females release eggs only once during the spawning season. Garcia-Cagide et al. (1994) and Claro and Lindeman (2003) reported that individual female mutton snapper are batch spawners, releasing eggs a number of times in a single month, but spawning only one month each year. Given the long mutton snapper spawning season and the wide range of egg sizes in gonads of mutton snapper sampled in March through the beginning of July 2009 on St. Croix, individual females are more likely batch spawners that spawn more than one month in a spawning season, similar to predictions for gray snapper (Bortone and Williams 1986). Table 1.7: Number of eggs produced by female mutton snapper (Lutjanus analis). # of Eggs
Size of Female (mm)
1,365,975
512 FL
Location
Rojas (1960) cited in Bortone and Williams (1986) Thompson and Munro (1983) cited in SEDAR15A - SAR3 Stevens (2004) citing Barbieri and Colvocoresses (2003)
1,355,000 373,000 1,400,000 534,781
South Atlantic 460 FL
Reference
Three year old hatchery reared female from Florida induced to spawn
Watanabe (2001)
256,943 393 - 653 FL St. Croix, U.S. Virgin Islands This study 3,189,777* *Number of eggs >0.35mm in ovary. Eggs did not appear to be hydrated. Watanabe (2001) reported that the mean diameter of eggs one hour after fertilization was 0.783mm (range = 0.725 to 0.875mm).
If an individual mutton snapper female spawns in two or more months in a single spawning season, the number of eggs produced per female could double, triple, etc., depending on the length of the spawning season and the number of months the female spawns. Clearly more work needs to be done to clarify the annual spawning frequency of both male and female mutton snappers to determine not only individual female fecundity but to accurately estimate the size of the spawning population. Both these factors are important in determining the status of the stock and developing management measures. Conclusions The spawning aggregation of mutton snapper in or near the MSSCA appears to be fairly robust based on the high CPUE reported in this study. This is despite fairly heavy fishing pressure that continued until the seasonal prohibition on possession of mutton snapper in territorial and federal waters 2006 went into effect. The skewed sex ratio of the catches, a result of a high proportion of small males, which start reproducing at a smaller size than females, may reflect high fishing 37
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
pressure before 2006 and the initial recovery of the population. Given the high female fecundity reported in this study, recovery may occur quickly if fishers continue to respect the seasonal possession prohibition and enforcement is adequate. The actual site of the mutton snapper aggregation still needs to be confirmed. Effort should be made to make visual dive inspections of the reefs near the Red Buoy site during the annual spawning period of mutton snapper. Also, visual dive inspections of reefs in this area at the spawning times of other species observed at the site would provide information about the importance of this site for these species and other species, for example, there have been reports of red hind spawning/aggregating in this area (Martinez pers. com.).
38
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
LITERATURE CITED - CHAPTER 1 Anderson, W.D. 2002. Lutjanidae. Pp. 1479-1504 In: Carpenter, K.E. (Ed.) The Living Marine Resources of the Western Central Atlantic. Volume 2: Bony Fishes. Part 2 (Opistognathidae to Molidae), sea turtles and marine Mammals. FAO Species Identification Guide for Fishery Purposes and American Society of Ichthyologists and Herpetologists Special Publication No. 5. 2002. Rome, FAO, 2127 pp. Anon. 2004. Reef Fish Spawning Aggregation Monitoring Protocol for the Meso-American Reef and the Wider Caribbean, Ver. 2.0. <http://collaborations.wcs.org/Portals/3/pdfs/Spawning_Aggregation_Monitoring_Protoc ol_4_July_2004_%5B1%5D.pdf>. Downloaded January 13, 2011. Barbieri L, Colvocoresses JA (2003) Southeast Florida reef fish abundance and biology. Fiveyear final report to the Department of Interior by the Florida Marine Research Institute, St. Petersburg. Beets, J. 1987. Profile of a collapsing fishery: V. Proceedings of the Conference on Fisheries in Crisis. J. deGraaf and D. Moore, eds. St. Thomas, USVI. Beets, J. and A. Friedlander. 1992. Stock analysis and management strategies for red hind, Epinephelus guttatus, in the U.S.V.I. Proceedings of the 42nd Gulf and Caribbean Fisheries Institute. 42: 66-79. Bortone, S.A. and J.L. Williams. 1986. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (South Florida) -- gray, lane, mutton, and yellowtail snappers. U.S. Fish. Wildl. Serv. Biol. Rep. 82(11.52). U.S. Army Corps of Engineers, TR EL-82-4. 18 pp. Burton, M.L. 2002. Age, growth and mortality of mutton snapper, Lutjanus analis, from the east coast of Florida, with a brief discussion of management implications. Fish. Res. 59(1-2):3141. Burton ML, KJ Brennan, RC Munoz and RO Parker Jr. 2005. Preliminary evidence of increased spawning aggregations of mutton snapper (Lutjanus analis) at Riley's Hump two years after establishment of the Tortugas South Ecological Reserve. Fish Bull 103:404-410. Brown-Peterson, NJ, DM Wyanski, F. Saborido-Rey, BJ Macewicz, and S.K. Lowerre-Barbieri. (ms). A standardized terminology for describing reproductive development in fishes. CFMC. 1993. Amendment 2 to the Fishery Management Plan for the Shallow-water Reef Fish Fishery of Puerto Rico and the U.S. Virgin Islands. Caribbean Fishery Management Council, San Juan, PR. 564 pp. CFMC and NOAA NMFS 2005. Comprehensive Amendment to the Fishery Management Plans (FMPs) of the U.S. Caribbean to Address Required Provisions of the Magnuson-Stevens Fishery Conservation and Management Act. Caribbean Fishery Management Council, San Juan, PR. 39
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Carson, E.W., E. Saillant, M.A. Renshaw, N.J. Cummings, and J.R. Gold. ms. Population structure, connectivity, and effective size of mutton snapper (Lutjanus analis) in the Caribbean Sea and northern Gulf of Mexico. Claro R. 1981. Ecologia y ciclo de vida del pargo criollo, Lutjanus analis (Cuvier), en la plataforma cubana. Informacion Cientifica Tecnica, Academia de Ciencias de Cuba. 186:183. Claro, R. J.A. Baisre, K.C. Lindeman, and J.P. Garcia-Arteaga. 2001. Cuban fisheries: historical trends and current status. In: Ecology of the Marine Fishers of Cuba (R. Claro, K.C. Lindeman, L.R. Parenti, eds.). Smithsonian Institution Press, Washington, D.C. pp. 194:219. Claro, R. and K.C. Lindeman. 2003. Spawning aggregation sites of snapper and grouper species (Lutjanidae and Serranidae) on the insular shelf of Cuba. Gulf. Carib. Res. 14: 91-106. Claro, R., Y. Sadovy de Mitcheson, K.C. Lindeman, and A.R. Garcia-Cagide. 2009. Historical analysis of Cuban commercial fishing effort and the effects of management interventions on important reef fishes from 1960-2005. Fish Res. 99(1): 7-16. Craig, A.K. 1966. Geography of fishing in British Honduras and adjacent coastal waters. Coastal Studies Laboratory Louisiana State University, Baton Rouge. Abstract and 1st page downloaded 18 Jan 2011. Delgado, P. 2004. The U.S. Caribbean Region, Wetlands and Fish: A Vital Connection, Fish, Crustaceans, and Mollusks Found in U.S. Caribbean Wetlands. NOAA National Marine Fisheries Service, Silver Spring, MD. 89 pp. Domeier, M.L., C. Koenig and F. Coleman. 1996. Reproductive biology of the grapy snapper (Lutjanidae: Lutjanus griseus) with notes on spawning for other western Atlantic lutjanids. In: F. Arreguin-Sanchez, J.L. Munro, M.C. Balgos and D. Pauly, eds. Biology, Fisheries and Culture of Tropical Groupers and Snappers. ICLARM Conf. Proc. 48:189-201. Druzhinin, A.D. 1970. The range and biology of snapper (fam. Lutjanidae). J. Ichthyol. 10:715735. Erdman, D.S. 1976. Spawning patterns of fishes from the northeastern Caribbean. Cont. Serv. Esp. VIII (2):1-36. Esteves-Amador, R.F. 2005. Dispersal of Reef Fish Larvae from Known Spawning Sites in LaParguera. MSc. Thesis, University of Puerto Rico, Mayaquez, Puerto Rico. 53 pp. Figuerola, M., D. Matos-Caraballo and W. Torres. 1998. “Maturation and Reproductive Seasonality of Four Reef Fish Species in Puerto Rio.” Proc. Gulf Carib. Fish. Inst. 50: 938968. Figuerola-Fernandez, M. and W. Torres-Ruiz. 2001. Aspectos de la biologia reproductiva de la sama (Lutjanus analis) en Puerto Rico y recommendaciones para su manejo. Departmento de recursos naturales y ambientales area de recursos vivientes negociado de pesca y vida silvestre laboratorio de investigaciones pesqueras. Froese R. and D. Pauly. 2007. FishBase. www.fishbase.org.
Electronic source document available at
García-Cagide, A., R. Claro and B.V. Koshelev. 1994 Reproducción. p. 187-262. In R. Claro 40
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
(ed.) Ecología de los peces marinos de Cuba. Inst. Oceanol. Acad. Cienc. Cuba. and Cen. Invest. Quintana Roo (CIQRO) México. Garcia-Moliner, Graciela. 2009. Quick reference to the fishing regulations history in the US Caribbean. SEDAR Caribbean Data Workshop, January 26-29, 2009. Caribbean Fishery Management Council, San Juan, PR. 12 pp. Geophysics GPR International, Inc. 2003. Marine Habitat Mapping Offshore St. Thomas & St. Croix US Virgin Islands EEZ, Final Report to the CFMC. Volume 2. pp. 21. Gold, J.R., E. Saillant, N.J. Cummings, and M.S. Renshaw. ms. Genetic divergence and effective size among lane snapper (Lutjanus synagris) in U.S. waters of the Western Atlantic. Gold, Jr., E. Saillant, N.D. Ebelt and S. Lem. 2009. Conservation genetics of gray snapper (Lutjanus griseus) in U.S. waters of the northern Gulf of Mexico and Western Atlantic Ocean. Copeia 2:277-286. Graham, R.T., R.Carcamo, K.L. Rhodes, C.M. Roberts and N. Requena. 2008. Historical and contemporary evidence of a mutton snapper (Lutjanus analis Cuvier, 1828) spawning aggregation fishery in decline. Coral Reefs. 27:311-319. Downloaded 18 Jan 2011. DOI 10.107/200338-007-0329-4. Gundersen, A.C., O.S. Kjesbu, K.H. Nedreaas, and A. Stene. 1999. Fecundity of Northeast Arctic Greenland halibut (Reinhardtius hippoglossoides). J. Northw. Atl. Fish. Sci. 25:2936. Heyman, W.D. and B. Kjerfve. 2008. Characterization of transient multi-species reef fish spawning aggregations at Gladden Spit, Belize. Bull. Mar. Sc. 83(3): 531-551. Huntsman, G. 1996. Lutjanus analis. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4. <www.iucnredlist.org>. Downloaded on 09 January 2011. Karlsson, S., E. Saillant and J.R. Gold. 2009. Population structure and genetic variation of lane snapper (Lutjanus synagris) in the northern Gulf of Mexico. Mar. Biol. 156:1841-1855. Mason, D.L. and C.S. Manooch III. 1985. Age and growth of mutton snapper along the east coast of Florida. Fish. Res. 3:93-104 (abstract). Matos-Caraballo, D., M. Cartagena-Haddock and N. Pena-Alvarado. 2006. Portrait of the fishery of mutton snapper, Lutjanus analis, in Puerto Rico during 1988-2001. Proceedings of the 57st Gulf and Caribbean Fisheries Institute. 57: 343-356. Munro, J.L. 2005. The assessment and management of Caribbean coral reef fisheries. Proc. of Gulf and Caribbean Fisheries Institute. 58:1-19. Murua, H. and F. Saborido-Rey. 2003. Female reproductive strategies of marine fish species of the North Atlantic. 33:23-31. Nemeth, R.S. 2005. Population characteristics of a recovering US Virgin Islands red hind spawning aggregation following protection. Mar Ecol. Prog. Ser. 286: 31-97. Ojeda-Serrano, E., R. Appeldoorn, and I. Ruiz-Valentin. 2007. Reef fish spawning aggregations of the Puerto Rican shelf. Caribbean Coral Reef Institute. Puerto. University of Puerto Rico. 31 pp. 41
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
<http://www.sefsc.noaa.gov/sedar/download/S14RD51%20CCRI%20SpawnAgg%20ID.pdf ?id=DOCUMENT> downloaded 10 January 2011. Olsen, D.A. and J.A. LaPlace. 1978. A study of a Virgin Islands grouper fishery based on a breeding aggregation. Proceedings of the 31st Gulf and Caribbean Fisheries Institute 31: 130-144. Olsen, D.A. and R.S. Wood. 1984. Ciguatera in the Eastern Caribbean. Review. 46(1):13-18.
Marine Fisheries
Paris, C.B., R.K. Cowen, R. Claro, K.C. Lindeman. 2005. Larval transport pathways from Cuban snapper (Lutjanidae) spawning aggregations based on biophysical modeling. Mar. Ecol. Prog. Ser. 296:93-106. Roe, R. 1975. Distribution of snappers and groupers in the Gulf of Mexico and Caribbean Sea as determined from exploratory fishing. Proceedings: Colloquium on snapper-grouper fishery resources of the Western Central Atlantic Ocean. Florida Sea Grant Program Rep. No. 17, pp. 129-164. Rojas, L.E. 1960. Estudios estadisticos y biologicos sobre el pargo criollo, Lutjanus analis. Cent. Invest. Pesq. Notas sobre Invest. 2. 16 pp. Quinn, N.J. and B.L. Kojis. 2010. Habitat description of the St. Croix, U.S. Virgin Islands south coast Mutton Snapper (Lutjanus analis) Conservation Area. Proceedings of the 62nd Gulf and Caribbean Fisheries Institute 62: 59-68. Saillant, E., S.C. Bradfield and J.R. Gold. 2010. Genetic variation and spatial autocorrelation among young-of-the-year red snapper (Lutjanus campechanus) in the northern Gulf of Mexico. ICES Journal of Mar. Sc. 67:1240-1855. SEDARI4-SAR2 (Southeast Data, Assessment Review 14 - Stock assessment Report 2). 2007. SEDAR 14: Stock Assessment Report 2: Caribbean Mutton Snapper. North Charleston, SC 194 pp. SEDAR15A-SAR3 (Southeast Data, Assessment Review 15A - Stock Assessment Report 3). 2008. South Atlantic and Gulf of Mexico Mutton Snapper. South Atlantic Fishery Management Council, Charleston, SC. 410 pp. Stevens, M.M. 2004. Commercially important Gulf of Mexico/South Atlantic snappers (red snapper, vermillion snapper, yellowtail snapper, with minor reference to gray snapper, mutton snapper, and lane snapper). Seafood Watch, Seafood Report, Monterey Bay Aquarium. Final Rpt. April 20, 2004. 29pp. Thompson, R. and J.L. Munro. 1983. In: Caribbean Coral Reef Fishery Resources, 2nd ed. (J.L. Munro, ed.). ICLARM, Manila, Philippines. 276 pp. Ungaro, N. 2008. Field manual on macroscopic identification of maturity stages for the Mediterranean fishery resources. GCP/PER/ITA/MSM-TD-21. MedSudMed Technical Documents No.21:34 pp. Watanabe, W.O. 2001. Species Profile: Mutton Snapper. SARC Publication No. 275. 11 pp.
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Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Webber, J.L. and J. Brown. 2008a. Spawning Aggregations: A Six-year Study in Saint Croix, USVI (2003 - 2008). Unpublished booklet prepared by The Nature Conservancy Southeast Caribbean Program, Saint Croix, USVI. 28 pp. Webber, J.L. and J. Brown. 2008b. Using lessons learned from six years of reef fish spawning aggregation site validation, collaboration, and outreach in St. Croix, USVI.
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Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
APPENDIX 1 Abstract submitted by Liam Carr to Gulf and Caribbean Fishery Institute for poster presentation at meeting in Venezuela in 2010. Poster was not submitted.
Age-frequency distributions of a protected mutton snapper (Lutjanus analis) aggregation following 17 years of protection Snappers have historically been a n important economic stock for the U.S. Virgin Islands, annually contributing nearly 4% of total landings by weight prior to seasonal closures set in place to prevent stock collapse. Evidence of depleted mutton snapper (Lutjanus analis) stocks in St. Croix led the Caribbean Fisheries Management Council into developing the Mutton Snapper Seasonal Area Enclosure (MSSAE) in 1993. The MSSAE closes fishing off at a historical fish spawning aggregation (FSA) site, during the March-June mutton snapper spawning season. Between March 2009 and June 2010, 139 mutton snapper were collaboratively harvested with St. Croix fishers within the MSSAE from an anchored fishing vessel at coordinates provided by local fishers. From this sample, 61 otoliths were collected and analyzed to develop agefrequency distributions, an important tool for creating growth curves and examining population structures. This analysis is part of the first effort since the MSSAE was enacted for gauging how successful management programs have been over the past 17 years for rebuilding local mutton snapper stocks. Researchers determined that the sampled population had a mean age of 6.5 ± 1.8 yrs, with a mode of 7 yrs. Additional analyses on length-frequency and weight-frequency distributions, along with examinations of gonadal conditions, provide preliminary evidence that the MSSAE’s historical FSA site remains active, although the size of the spawning population continues to be difficult to assess.
44
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
CHAPTER 2 Habitat Description of the St. Croix, U.S. Virgin Islands Mutton Snapper Seasonal
INTRODUCTION The Mutton Snapper Seasonal Closed Area's (MSSCA) northern boundary is located approximately 4km off the south-western point of the island of St. Croix, U.S. Virgin Islands (USVI) (Fig. 2.1). The MSSCA lies north and south of the edge of the insular platform (approximately 25m contour) and is 4.5km long and 2.2km wide with depths from 12m to >200m (the shelf outer slope) (Fig. 2.2). Figure 2.3 is a bathymetric image of the MSSCA to depths of >50m showing the high rugosity of the southern half of the MSSCA and the steep drop off at the edge of the shelf.
Figure 2.1. Mutton Snapper Closed Area off St. Croix, USVI (see Fig. 1.1 for coordinates).
45
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.2. Example color bathymetry near the edge of the island shelf in the MSCA (GPR 2003). The red / orange colors represent depth around 12-18m with the dark blue colors represents depths 25-30m.
Figure 2.3. Multi-beam side scan sonar image of Mutton Snapper Closed Area (GRP 2003). The red / orange colors represent depths of 12-18m with yellow representing depths of 25-30m and green depths of around 25-30m. The depth legend on the chart is not entirely accurate for shallower depths according to GRP (2003). Some interesting topography was present in SSS images just before the outer reef on the southern shelf edge. Although no spawning aggregations were observed during ten dusk dives in April – June 2009, 65 ripe Lutjanus analis males and 30 ripe females were caught in a habitat similar to that depicted in Figures 2.2, 2.3 and 2.4 showing flat sandy moats separating raised reefs. 46
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.4. Side scan sonar mosaic showing sandy moat between two reefs (after Prada 2003). The reef to the south was the last reef before the shelf edge slope. The habitat depicted in this image is similar to the site where many reproductively mature Lutjanus analis were caught from April – June 2009. Using mosaics in geotiff format from Side Scan Sonar (SSS) imagery processed at 0.2m resolution, Prada (2003) generated detailed benthic habitat maps (Fig. 2.5) through visual interpretation and delineation. Rivera (et al 2005) used SSS to detect fish aggregations in three MPAs. Fish aggregations in the MSSCA were significantly smaller than fish aggregations at the Marine Conservation District off St Thomas and the Lang Bank closed area off St Croix (Rivera et al 2005). Prada (2003), however, was unable to provide an estimation of habitat classification accuracy of the maps for the MSSCA because of a lack of in water verification. GOPL and ALIN were two of the major habitat types in the MSSCA. She consequently considered that their classification may need correction and recommended that additional ground truth information be collected for the full set of habitats in order to:
better classify SSS mosaics not having distinct echo-returns nor sharp boundaries as observed, for instance at the Gorgonian Plain (GOPL) habitats, and be able to estimate map accuracy for the Algae with Invertebrates (ALIN) habitat type.
47
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
SAIN 1
Figure 2.5. Mutton Snapper Seasonal Closed Area showing topographic relief and depth. The benthic sites sampled are marked.
48
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
SAIN 1
Figure 2.5. Classification of benthic habitats in MSSCA (provided by J. Blondeau from images provided by Prada 2003) with sites sampled.
49
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Prada's (2003) habitat descriptions (Table 2.1) were derived from SSS and multi-beam data within the MSSCA. These habitats were defined by Prada (2003) using modifications of the scheme created by NOAA for the shallow waters of Puerto Rico and U.S. Virgin Islands (NOAA-NOS 2001). Having more detailed habitat information, will not only benefit future users with more accurate maps, but also will allow complete habitat definitions.
Knowledge of the spatial distribution patterns of habitat is essential information for scientists and managers in order to maintain important Essential Fish Habitat within areas under legal protection and conservation (Prada 2003). The purpose of this effort was to provide detailed in water verification of the classifications with metrics of dominant fauna / flora and substrate types and to characterize the temperature variation during the period of spawning. Prada's (2003) habitat descriptions (Table 2.1) were derived from SSS and multi-beam data within the MSSCA. These habitats were defined by Prada (2003) using modifications of the scheme created by NOAA for the shallow waters of Puerto Rico and U.S. Virgin Islands (NOAA-NOS 2001). Having more detailed habitat information, will not only benefit future users with more accurate maps, but also will allow complete habitat definitions.
Knowledge of the spatial distribution patterns of habitat is essential information for scientists and managers in order to maintain important Essential Fish Habitat within areas under legal protection and conservation (Prada 2003). The purpose of this effort was to provide detailed in water verification of the classifications with metrics of dominant fauna / flora and substrate types and to characterize the temperature variation during the period of spawning. The MSSCA comprises 692.4ha. The specific area of each of the benthic habitats as determined by Prada (2003) is listed in Table 2.2. In some cases the distinction between the habitats is clear, while in other cases the change is gradual so the values should be considered approximate.
50
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table 2.1. Hierarchical classification scheme developed by Prada (2003) to generate detailed habitat maps around the USVI. The table lists the benthic habitats found in the MSSCA. Description of the Habitat Codes follows. Meta Community Coral and gorgonians on consolidated sediments Submerged Aquatic Vegetation on unconsolidated sediments Bare or mixed invertebrates on unconsolidated sediments
Subcommunity
Habitat Types
Coral Patch
Coral Patch
COPA
Coral Low Relief
Coral Limestone
COLI
Plains
Gorgonian Plains
GOPL
Dense Algae
DEAL
Sparse Algae
SPAL
Algae and Invertebrates
ALIN
Sand Invertebrates
SAIN
Sand No Ripple
SANR
Sand Ripple
SARI
Community
Corals
Gorgonians
Macro-algae
Sand
Algae on Sand
Coarse Sand
Habitat Codes
Table 2.2. Total area (ha) of benthic habitats for the MSSCA (after Prada 2003)
Total (ha) % area
COPA 4.7
COLI 15.6
GOPL 102.9
ALIN 341.3
DEAL 2.8
SPAL 13.6
SANR 48.2
SARI 0.4
0.68% 2.25% 14.86% 49.29%
0.40%
1.96% 23.53% 6.96%
0.06%
51
SAIN 162.9
Total 692.4
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
METHODS - BENTHIC SURVEY Using an on board GPS device, a lead line with a float attached was tossed upon reaching the coordinates for each site. Divers then descended the line to the bottom and deployed the transect tape, usually in a radial pattern from the lead. Twenty quadrats (0.25m2) were photographed using an Olympus SW1030 digital camera along at least five 20m transect lines at each of the habitats described by Prada (2003) within the MSSCA. The sampling protocol assessed benthic composition using CPCe 3.6 software (Kohler and Gill 2006), habitat type, and coral health. The photos were classified into substrate categories and percent cover of nine substrate categories calculated. Corals, gorgonians, and some algae were identified to species or genus. Diseases and bleaching of hydrocoral and scleractinian coral colonies within the quadrat were recorded.
52
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
RESULTS – BENTHIC SURVEY A brief description of each habitat type found is presented below along with a sample of the Side Scan Sonar (SSS) imagery representative of the image/habitat variability. Each SSS image sample from (Prada 2003) is shown at the scale 1:1000 and represents an area of 625m 2 (0.0625ha). A summary table (Table 2.3) of the CPCe analysis shows the distribution of the benthic categories across habitats. Detailed summary descriptive statistics for each benthic category at each site in each habitat is listed in Appendices - Chapter 2 (A2), Tables A2-2.1 – A2-2.9. Detailed summary descriptive statistics for corals, gorgonians and algae at each site in ALIN, COLI, GOPL and SAIN habitat is list in Tables A2-3.1 – A2-3.10.
Table 2.3. Comparison of the percentage of invertebrate and substrate cover habitat classifications (Prada 2003) in the MSSCA. More detail for each site in each habitat is available in Tables A2-2.1 – A2-2.9. Tables A2-3.1 – A3.10 contain descriptive statistics for corals, gorgonians and algae in selected habitats. COPA COLI GOPL DEAL SPAL ALIN SAIN SANR SARI Coral
5.25
7.56
7.00
0.15
0.85
2.19
2.30
0.16
0.30
Gorgonian
0.75
3.87
3.43
0.00
0.00
0.09
0.48
0.00
0.00
Sponge
6.80
16.20
12.74
1.98
3.55
6.29
6.96
6.40
1.65
Zooanthids
0.00
0.05
0.00
0.00
0.00
0.01
0.00
0.00
0.00
Macro algae
33.90
26.16
17.69
1.33
19.73
23.70
22.18
4.94
1.25
Turf Algae & Other Live
2.25
20.99
14.85
5.83
40.94
50.79
29.68
22.91
14.70
Dead coral
36.35
16.72
10.40
1.90
0.38
0.34
2.23
2.14
0.00
Coralline algae
7.90
3.35
1.66
0.03
0.13
0.58
0.08
0.10
0.00
Diseased coral
0.00
0.11
0.05
0.00
0.00
0.00
0.04
0.09
0.00
Sand, rubble, etc. # sites surveyed for each habitat Area Sampled m2
6.80
5.01
32.19
88.8
34.43
16.03
36.08
63.26
82.10
1
5
4
2
2
4
4
4
1
25
125
100
50
50
100
100
100
25
Using the Agglomerative Hierarchical Clustering (XLSTAT 2010) analysis on the CPCe benthic categories by habitat matrix (Table 2.3), classifying Pearson correlation coefficients and agglomerating using weighted pair-group averages resulted in the clusters in Figure 2.6. At the 0.85 similarity level there are four major clusters. The first clusters are coral reef on consolidated sediments (COLI, COPA), coral and gorgonians on plains with a large amount of rubble (GOPL). The next clusters are on unconsolidated sediments ALIN, SPAL and SAIN are characterized by the large amount of macroalgae while SANR, DEAL and SARI are macroalgae depauperate, having the least macroalgae of all habitats.
53
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
0.06 0.16 0.26
Similarity
0.36 0.46 0.56 0.66 0.76 0.86
SARI
DEAL
SANR
GOPL
SAIN
SPAL
ALIN
COLI
COPA
0.96
Figure 2.6. Dendrogram of CPCe benthic categories by habitat matrix, classifying using Pearson correlation coefficients and agglomerating using weighted pair-group averages. Dotted line represents truncation into four major clusters at 0.85 similarity. Prada (2003) Habitat Type - Submerged Aquatic Vegetation on Unconsolidated Sediments ALIN - Algae with Invertebrates Algae with Invertebrates (ALIN) was surveyed at four sites in 2009 and 2010. ALIN is a flat carbonate pavement habitat with a thin veneer of sand and turf algae, with some cyanobacteria, collectively representing 66.82% of the substrate (Table 2.3). It is the largest habitat (341.3ha) with only 2.19% live coral cover with no diseased coral. Clypeaster rosaceus individuals were common at some sites, both as live individuals and dead tests (Fig. 2.7). Macroalgae (primarily Saragassum, Lobophora and some Dictyota) covered 23.70% of the substrate. The relief is uniformly flat except for occasional shallow depressions, some with holes and coral rubble; scattered heads of dead and living coral; and a few gorgonians and sponges.
54
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.7. ALIN 1 - Clypeaster rosaceus test. Figure 2.8 are SSS images of ALIN from Prada (2003). The middle image (b) does not look similar to the other images (a, c). No details were given by Prada (2003) as to why these images were considered representative of ALIN. The end images (a, c) show a light / dark banding pattern while image b appears to show more relief. This could represent the variation in algal cover and rugosity between ALIN habitats as exhibited in (Fig. 2.9 and Fig 2.10).
a b c Figure 2.8. Side Scan Sonar images (Prada 2003) of ALIN generally show few features.
55
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.9. ALIN 2 site in July 2, 2009 showing the sandy bottom interspersed with algal clumps, sponges and small coral heads.
Figure 2.10. Variation in ALIN habitat mapped by Prada (ALIN 1 - June 20, 2009) is demonstrated in this photo by the lack of macro algae on the flat, hardbottom substrate. Macroalgae primarily was found on dead coral in this variation of ALIN habitat. 56
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
SPAL - Sparse Algae SPAL covers only a relatively small area of the MSSCA. Prada (2003) described SPAL (Sparse Algae) as similar to ALIN except that ALIN had more invertebrates, which gave additional structure to the habitat. Both SPAL and ALIN were dominated by a combination of macro and turf algae (includes cyanobacteria) (ALIN - 74.49% algae: 23.70% macro algae, 50.79% turf algae; SPAL - 60.67% algae: 19.73% macro algae, 40.94% turf algae – Table 2.3). Both habitats only had a small amount of live coral with ALIN having >2 times the coral cover of SPAL: ALIN 2.19% and SPAL 0.85%. The mean density of sponges was also greater in ALIN, but this was due to a single ALIN site that had several large barrel sponges (Xestospongia muta). The irregular sea urchin, Clypeaster rosaceus, was common, camouflaged among the algae and the occasional shallow ledges and solution holes with rubble provided habitat for octopus and small to medium size fish (Fig. 2.11 a, b). The surface consists of areas of algae mixed with shallow sand patches, small primarily dead coral heads, occasional sponges with the bottom dominated by turf algae and patches of macroalgae (Sargassum, Lobophora and Dictyota) (Fig. 2.12). The habitat did not have distinct boundaries. SPAL is another hard bottom habitat with generally little vertical relief and is very similar to ALIN (Fig. 2.13). A
B
Figure 2.11. SPAL 1 - Clypeaster rosaceus were abundant (left) in this habitat. Sand channels with ledges added some rugosity to an otherwise two dimensional, flat habitat (right).
57
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.12. Close up of SPAL site showing high cover of macro and turf algae.
Figure 2.13. SPAL habitat showing lack of vertical relief, no live gorgonians, a solitary vase sponge and dense cover of macro and turf algae. 58
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
The uniformity of the habitat observed in 2009 / 2010 did not support Prada’s observation (2003) that the light and dark banding in the SSS images were associated with algae and sand patterns (Fig. 2.14 a, b, c). We suggest that the SSS images may be placing greater importance on the reflective nature of the substrate rather than the thin veneer of live biota.
a
b
c
Figure 2.14. Prada (2003) suggested that the dark and light bands in the side scan sonar images corresponded to the algae and sand respectively. DEAL - Dense Algae Prada (2003) considered that Dense Algae (DEAL) was characterized by dense fleshy algae patches which resulted in a dark and uniform side scan sonar return (Fig. 2.15). No suggestion was given by Prada (2003) to explain the banding observed.
a b c Figure 2.15. SSS images from Prada (2003) show the uniform dark signal (a) which was interpreted as dense algae. DEAL habitat consisted mainly of sand (63.26%) followed by turf algae/ cyanobacteria (22.91%) (Fig. 2.16, Table 2.3). Scattered primarily dead coral heads and some dead branches of A. cervicornis branches provided low relief (Fig. 2.17). The percent coral cover based on 4000 points from 200 quadrats (50m2) was 0.15%. Sand is at least 13cm deep in some places and is covered in many places with either tufts of brown cyanobacteria with dead white bases or brown, yellow or blue green cyanobacteria film. Some live green algae and the calcareous remains of Halimeda, were present, but live macro algae was rare (1.33% cover). The predominance of sand in the site (63.25%) makes it effectively indistinguishable from SANR (sand 88.80%, Table 2.3).
59
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.16. 2009 photo showing DEAL habit devoid of dense meadows of fleshy algae.
Figure 2.17. Coral rubble and remnants of Acropora cervicornis on the sandy bottom in DEAL in 2009. 60
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Prada (2003) Habitat Type - Bare or Mixed Invertebrate on Unconsolidated Sediments SANR - Sand No Ripple Sand No Ripple (SANR) was a flat, sand substrate, with low relief rocks, rubble (63.26%, Table 2.3) and small sponges (6.40%) (Fig. 2.18). SANR were biogenetic sandy channels between two linear coral limestone reef systems (COLI) or between COLI and GOPL habitats. Sand was generally deeper toward center of the channel with pavement along edges. Small to medium sized coral rubble was scattered on the sand, particularly along the edges of the channels where Strombus gigas were found (Fig. 2.19). Turf algae / cyanobacteria also covered large areas, 22.91% (Table 2.3, Fig. 2.20).
Figure 2.18. SANR is dominated by a sandy substrate with sporadic patches of turf algae / cyanobacteria and small clumps of limestone.
Figure 2.19. Queen conch, Strombus gigas, was commonly observed in SANR. 61
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.20. Film of cyanobacteria covers much of SANR and DEAL habitats. Dead coral covered 2.14% of the bottom. Of the 0.16% live coral sampled over half of it (0.09% of the total cover sampled; Table 2.3) was diseased. The habitat is similar to SAIN but without abundant invertebrates which function to increase habitat structure. The dominant biota is turf algae / cyanobacteria (22.91%). Prada (2003) offers no explanation for the obvious variation in light intensity SSS (Fig. 2.21 a, b) or for the distinctive uniform discontinuities in Fig. 2.21c considering that the habitat was termed Sand No Ripple.
a
b
c
Figure 2.21. Prada (2003) notes that the lack of large macro invertebrates in SANR results in a lack of habitat complexity and strong continuous reflections from the sand. SAIN - Sand Invertebrates The habitat termed sand invertebrates (SAIN) was described by Prada (2003) as coarse biogenic sand on unconsolidated sediments with sparse coral (2.30%) and gorgonian colonies (0.48%) (Table 2.3). We found that the habitat was primarily consolidated sediments with a thin veneer of sand with scattered sand patches where the sand was relatively deep (36.08%) (Fig. 2.22). 62
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.22. SAIN habitat had sandy patches over pavement with occasional gorgonians, sponges, and live and dead coral heads. Unlike SANR, SAIN contained a diverse invertebrate community which increased habitat structure as see on the SSS images (Fig. 2.23). Prada (2003) considered that the SSS pattern was characterized by its strong and continuous reflection from the sand. We suggest that consolidated sediment would reflect a stronger signal than unconsolidated sediment like sand.
a b c Figure 2.23. Side Scan Sonar images show irregularities caused by invertebrate and limestone clumps. SARI - Sand Ripple Sand Ripple (SARI) habitat was the smallest in area (0.4ha) of the habitats. Prada (2003) characterized SARI as small biogenetic sand patches. Sand comprised 82.10% of the cover (Table 2.3). Patches of SARI habitat were only large enough for a few 20m transects. The sand was commonly less than 10cm deep over the limestone pavement (Fig. 2.24). Turf algae / cyanobacteria were the dominant biota (14.70%, Table 2.3). Some coral rubble – old branches of A. cervicornis and & dead “coral heads” of primarily Montastrea annularis (complex) are scattered throughout in the habitat. Gorgonian Plains (GOPL) habitat was adjacent and there was a clear division between the two habitats (Fig. 2.25) which is evident by the sharp pattern changes on SSS images (Fig. 2.26). 63
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.24. Sand and Acropora cervicornis rubble dominant SARI habitat in 2009. The adjacent GOPL habitat can be seen in the background.
Figure 2.25. Sharp interface between SARI habitat on the right and GOPL habitat on the left.
64
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
a b c Figure 2.26. Sand with ripple marks but had distinct discontinuities in the SSS imagery (Prada, 2003). Arrows undefined in Prada.
Coral and Gorgonians on Consolidated Sediments COLI - Coral Limestone Prada (2003) noted that Coral Limestone (COLI) was divided by sand channels, which is commonly called “spur and groove” (Fig. 2.27). She also noted that it had a high vertical relief that exceeded 10m in some regions (Fig. 2.28). Over 78.8% of the substrate was covered with live biota. Although COLI had the highest percentage of live coral cover (7.56%, Table 2.3) and coralline algae (Porolithon pachydermum) (3.35% of the substrate) of the habitats within the MSSCA, coral and coralline algae cover were still considered low. The reef was not considered healthy and showed signs of stress. Coral disease was not prevalent. Only 1.5% of the live coral was diseased and only about 1.1% was considered “recently killed coral”. This suggests that while coral mortality owing to disease was occurring, there was no major disease outbreak during the sampling period. However, it was clear that coral cover had been much higher in the past as "dead coral" covered 16.72% of the substrate. The category "dead coral” was defined as substrate with obvious coral structure that was not recently killed but had not been eroded or covered with algae. The live coral in COLI had either died several years ago or had slowly died over several decades. Although there was extensive dead coral, coral plates that overhung the sand channels between reefs were still in place (Figs. 2.27, 2.29), suggesting that mortality had been relatively recent and insufficient time had passed for storms and/or boring organisms to erode and dislodge them. Also, gaps in the reef had not filled with sediment, coral rubble, or biota. While coral diversity was high in this habitat, coral cover was currently, and apparently historically, dominated by the Montastrea annularis species complex Table A2-3.1). This was evident from the preponderance of fragments of live M. annularis on the large hemispherical and the plate-like coral heads that dominated the COLI reefs and the hemispherical shape and relatively smooth surface (i.e. lack of ridges characteristic of Colpohyllia and Diploria colonies) of totally dead colonies (Fig. 2.30). Hemispherical and plate-like M. annularis overhung the grooves forming ledges. It is likely that the decline in coral cover has been occurring over a long period and events such as the 1993 (Quinn and Kojis 1999), 1998, and the 2005 coral bleaching episodes and accompanying disease-related mortality have been the main contributors to this decline.
65
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Sponges were the dominant animal in the habitat, comprising 16.20% of the substrate cover (Table 2.3). Macro algae, primarily Lobophora variegata, extensively covered the dead coral substrate.
Figure 2.27. Deep groves between limestone spurs were characteristic of coral limestone habitat.
Figure 2.28. The high relief of the coral limestone (COLI) habitat is visible in this photograph. 66
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.29. The edge of reef with coral colonies overhanging sand channel, creating ledges.
Figure 2.30. Montastrea annularis species complex coral head showing live fragments with partial mortality of the coral colony. 67
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
The “spur and groove” relief and structural complexity is evident in SSS imagery (Fig. 2.31). The structural complexity of the reef provides a lot of shelter for many species of fish.
a
b
c
Figure 2.31. The high vertical relief in the coral limestone habitat is easily recognized in the side scan sonar images. The characteristic “spur and groove” is very apparent in image c. COPA - Coral Patch Coral Patch was a small habitat of continuous corals and was considered similar to Coral Limestone habitat (COLI) in 2002 (Prada 2003) (Figure a, b). In 2009 / 2010 no COPA habitat was detected in areas labeled COPA on Prada's (2003) habitat maps in the northern half of the MSSCA (COPA 1 and 2). The habitat at COPA 1 and 2 (Fig. 2.32) was surrounded by SAIN and ALIN habitat on Prada's map. The habitat seen during dives at representative GPS coordinates for COPA in these two areas was flat pavement with sand (6.80%) and macro algae (33.90%, Table 2.3) with occasional large Xestospongia muta and many smaller sponges (6.80%, Table 2.3). COPA 1 and 2 habitats were similar to Algae and Invertebrates (ALIN) or Sparse Algae (SPAL). Large, shallow depressions filled with coral rubble and sand occurred throughout the habitat. These depressions have ledges along the edges and provide shelter for lobsters and several species of fish (Fig. 2.33). The subsurface strata may be different from the surrounding habitat resulting in the different acoustic signal Prada observed. The habitat has either changed drastically since Prada (2003) did her field work or was misidentified. Therefore, we have excluded it from further analysis. The COPA 3 site that we surveyed was a deeper water site located within COLI habitat. The site we surveyed was identical to the surrounding COLI habitat. However, in 2009, during a diver search for mutton snapper, COPA habitat was observed. This COPA habitat was within or adjacent to COLI habitat and was similar to COLI except for the lack of grooves for a couple hundred meters. COPA had high relief with a sharp boundary in SSS images (Fig. 2.34 a, b, c). We hypothesize that the solution holes (Fig. 2.35) in the substrate created the distinct boundaries in the SSS images. A variety of fish including squirrelfish and French and white grunts congregate in these depressions during the day.
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Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.32. Habitat observed at GPS coordinates for COPA 1 in June 2010. This habitat was a fairly flat carbonate pavement with a thin veneer of sand, which was dominated by algae with occasional sponges and dead and living coral heads.
Figure 2.33. Spiny lobster being photographed in the COPA habitat as it leaves its den in the depression at the right middle of the photograph (August 2009).
69
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
a
b
c
Figure 2.34. Side Scan Sonar of COPA from Prada (2003). The authors consider the sharp boundaries to probably be the solution pit ledges.
Figure 2.35. Pavement in sites designated COPA by Prada (2003) is disrupted by these depressions which are often have ledges around their perimeter and contain sand and coral rubble (photograph June 1, 2010). GOPL - Gorgonian Plain Gorgonian Plain (GOPL) was the third most abundant habitat in the MSSCA with 102.9 ha. Prada (2003) described this habitat as "flat and extensive areas covered by gorgonian colonies mixed with scleractinian corals." She noted that GOPL habitats in the USVI had a higher percentage of scleractinian corals compared to La Parguera, Puerto Rico. She also noted that this habitat did not have a distinct boundary with adjacent habitat. In contrast, we found that this was a distinctive habitat at the sites we surveyed. This habitat often had considerable vertical relief and usually consisted of large carbonate mounds with corals, gorgonians and sponges scattered over the surface (Figs. 2.36). These mounds rose above surrounding SPAL, ALIN, DEAL and SANR habitats. Vertical relief of GOPL habitat was 70
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
highest just north of COLI habitat, but declined as to the north. GOPL rises could have been part of a series of ancient reefs that paralleled the shelf edge. The inner reefs (GOPL habitat) may have declined as sea level rose and flooded the shelf making the habitat inimical to scleractinian coral survival. It is not clear, why, today, this habitat lacks evidence of extensive coral cover similar to COLI. GOPL may give an impression of pavement where this habitat is extensive. However, the edges of this habitat always showed a sharp rise above the surrounding substrate (Fig. 2.37). GOPL habitat was covered mostly by macroalgae (17.69%), sponges (12.74%), turf algae / cyanobacteria (14.85%), live coral (7.00%) and gorgonians (3.43%) (Table 2.3). Lobophora variegata was the dominant macro algae and Dictyota was the subdominant macro algae in the shallower GOPL sites. Gorgonians were as abundant in GOPL as they were in COLI (3.87%). The presence of dense invertebrate communities and limestone rocks cause the regular patterned SSS image in Fig. 2.38. About 32.19% of the substrate was sand or rubble. GOPL had the second highest occurrence of coralline algae (1.66%). Only 0.05% of the live coral was diseased (Fig. 2.39). A relatively large, healthy population of Acropora cervicornis about 10m x 15m was observed at 18m in July 2010 (Fig. 2.40). There were no sign of predation or disease in the population.
Figure 2.36. GOPL habitats were distinct from adjacent habitats (GOPL 3, photo May 5, 2010).
71
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.37. Sponges and gorgonians stand out among the macroalgae covering the dead coral colonies in GOPL 1 (left, June 26, 2009). Dense invertebrate populations and limestone rocks characterized GOPL (right, April 30, 2010).
72
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
a b c Figure 2.38. According to Prada (2003) GOPL (gorgonian plain) did not present a distinct boundary with its adjacent habitats.
Figure 2.39. White plague disease on Montastrea annularis at GOPL 4 (July 2, 2009).
73
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.40. Healthy population of Acropora cervicornis in GOPL (May 30, 2010), depth 13m. The lionfish, Pterois volitans, an invasive species to the Caribbean from the Pacific Ocean (Snyder and Burgess 2007), was observed for about 5 min. in GOPL habitat at 18m in July 2010 during a mutton snapper search dive (Fig. 2.41). The fish showed no defensive behavior and did not try to seek shelter. This was the only individual observed during the surveys. It was not killed owing to lack of equipment for killing or collecting when initially sighted and the inability to find it again at end of the dive when G. Martinez searched for it with spearfishing gear. Several Ginglymostoma cirratum, (nurse shark) were observed at several habitats in both years (Fig. 2.42). This was the only shark species observed.
Figure 2.41. The lionfish, Pterois volitans (~SL 15cm), an invasive species, observed in GOPL at 18m (July 2010). 74
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Figure 2.42. A nurse shark (Ginglymostoma cirratum), ~1.5m TL, observed cruising over GOPL habitat (GOPL 3, May 5, 2010). Note the ubiquitous consolidated substrate with shallow sand pockets, coral rubble, gorgonians, sponges and dead/live coral heads.
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Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
DISCUSSION - BENTHIC SURVEY Mean percent cover for the fauna / flora and substrate and depth for each survey site and each habitat is found in Appendicies - Chapter 2 Tables A2.2.1 - A2.2.9 covering a total of 675m2. Live scleractinian coral cover was very low. Habitats such as COLI and GOPL (Table A2.2.3) that had a strong 3D structure created by corals only had a coral cover of 7.56% and 7.00% respectively. The Montastrea annularis species complex was the dominant coral taxa in both COLI and GOPL (Table A2-3.4) habitats. Similarly, at a mesophotic coral reef on nearby St. Thomas (Smith et al 2010) M. annularis was also the dominant coral, though coral cover was higher on the mesophotic reefs (23% vs. 7% in COLI in the MSSCA on St. Croix). The dead coral skeletons COLI and GOPL had high macro algal cover, primarily Lobophora variegata. In shallower habitats such as ALIN Sargassum spp. were more common (Table A23.7) while Dictyota was most abundant in SAIN (Table A2-3.9). In the largest habitat, the predominately shallow ALIN and SAIN habitats, Siderastrea siderea was the most abundant coral. However, this species only covers 0.96% of the substrate (Table A2-3.6) in ALIN and 0.68% in SAIN (Table A2-3.8). Coral cover in similar habitats outside the MSCA had been around 30% prior to the 2005 bleaching event (T. Smith, pers. com.). Work by Adey et al (1981) on the southern St. Croix reefs only investigated inshore shallow reefs. Their closest site to the MSSCA, Airport Reef, was sampled to a depth of only 7m. Unlike the more eastern reefs that they sampled, no Acropora palmata was observed. The percent coral cover was 17.2%, with 69% macroalgae, 14% sand and 0.1% coralline algae. While not stating the reefs were overfished, they noted that studies involving fish (Randall 1963, 1967) and urchins (Sammarco et al. 1974) had demonstrated that herbivores were not only capable of lowering algal biomass but they also can create an environment that favors algal species with high rates of growth over the other, slow growing macroalgae which are better space competitors. They further noted that larger fleshy benthic algae, with more rapid growth rates than coral, are quite capable of out competing corals and coralline algae for space, and that without the effects of grazing, reefs could not develop their carbonate structure. Adey et al (1981) reported over 100 species of algae in the algal turfs in the shallow reefs at the east end of St. Croix. A relatively few species of blue-green algae dominated the turf. The taxonomy has changed and the Phylum is now referred to as Cyanobacteria. The very thin layer of sand over hard bottom led Prada (2003) to misidentify the Meta Community for SAIN, SPAL and ALIN as “unconsolidated sediments” from the side scan signal. This Meta Community should be renamed SAV on consolidated sediments. DEAL is also a hard bottom habitat, but with more sand. Prada described GOPL as flat areas covered mostly by gorgonian and sponge colonies and without a distinct boundary with adjacent habitats. In fact, this habitat often had considerable vertical relief and usually consisted of extensive carbonate mounds with corals, gorgonians and sponges scattered over the surface. GOPL appears to be the remnants of a relict reef system once likely similar to COLI. The underlying surface of the relict GOPL reef has been smoothed by infilling of interstices and erosion of the surface. It provides a hard, angular settlement surface for larvae and as a result has a relatively 76
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
high cover of sponges, gorgonians, and corals compared to the flat, hard bottom habitats, i.e. ALIN, SPAL, SAIN and DEAL.
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Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
WATER TEMPERATURE ON ST. CROIX INTRODUCTION Water temperature is an important driver of reef health and reproductive timing in invertebrates and possibly fish. Water temperature data were collected during this the main spawning months of Lutjanus analis.
MATERIALS AND METHODS - TEMPERATURE A ReefNet brand underwater temperature logger, attached to a diver, was used to measure subsurface sea water temperatures every 10 seconds during dives in May and June 2009 and May, June and July 2010. The temperature logger automatically recorded water temperature at preset intervals once it was immersed to 3m. Subsurface sea water temperatures were measured during several dives to depths ranging from 10-28m. The monthly mean was calculated from observations starting at least 5 min into the dive. A detailed analysis of temperature variation is beyond the scope of this report.
RESULTS - TEMPERATURE The mean temperature in May 2009 was 27.7oC (N = 8) and was 28.4oC in June 2009 (N = 3). The temperature range in May was only about 0.2oC while it ranged nearly 0.8oC in June. Heavy rains in June 2009 resulted in the discharge of freshwater at a depth of 22 - 28m at SANR 5 (sand channel behind the outer shelf edge reef, COLI) creating a cooler, lower salinity layer (Fig. 2.43). The increase in temperature from May to June was consistent with ten years of subsurface sea water temperature observations from a reef in St. Thomas, USVI (Quinn and Kojis 2003).
Figure 2.43. Mean subsurface sea water temperature during dives in May 2009 (N=8) and June 2009 (N=3). 78
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Subsurface sea water temperatures were much warmer in 2010. The mean temperature in May 2010 was 28.31oC (N = 5), 29.22oC in June 2010 (N = 4) and 29.40oC in July 2010 (N=3). May 2010 was 1.61oC warmer than 2009 and June 2010 was 0.91oC warmer (Fig. 2.44). As expected, temperature varied slightly with depth.
Table 2.4. Mean monthly subsurface seawater temperature in the MSSCA in 2009 and 2010. Temperature oC Difference oC
Date May-09
27.30
May-10
28.91
Jun-09
28.31
Jun-10
29.22
Jul-10
29.40
1.61
0.91
Annual Variation in Subsurface Seawater Temperature in 2009 and 2010 at the MSSCA Water temperature oC
29.7 29.2 28.7 2009 28.2
2010
27.7 27.2 May
June
July
Figure 2.44. Subsurface sea water temperatures warmer in 2010 during the period of closure.
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Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
DISCUSSION - TEMPERATURE Variations in mean monthly water temperature between 2009 and 2010 did not appear to affect the timing of the onset of spawning. The presence of immature gonads in Lutjanus analis caught in March 2009 and 2010 suggests that the increased water temperature in 2010 had not altered the timing of gonad development in 2010. However, the effects of sustained increases in water temperature on fish populations are unknown and require further study if fisheries management policy is going to adapt to climate change. No bleaching of corals was observed during dives from April to early August 2009 and during May to July 2010. Bleaching would not be expected, even with the higher water temperatures in 2010, during these months. Corals historically have bleached, even in warmer years, primarily in September and October. To protect coral reef habitat, especially because of its importance to fisheries, the Caribbean Fishery Management Council (CFMC) banned bottom tended fishing gear (traps, bottom long lines, etc.) in the MSSCA. However, the USVI, which has jurisdiction over most of the MSSCA has not followed suit. It would behoove the USVI to also ban bottom tended gear within at least a portion of the MSSCA under its jurisdiction. The seaward or southern half of the MSCA contains the remnants of magnificent reef structures which, over time, might recover from the 2005 bleaching event which affected all Virgin Islands reefs (Miller et al 2006, Rothenberger et al 2008). Nearly thirty years ago Adey et al (1981) observed that the surest approach to maintaining natural conditions is to prohibit all land and water use in the neighborhood of the reef. However, this statement is less true in 2010. While local impacts to reefs can certainly degrade or destroy reefs, regional and global factors are having more of an impact on reefs today. The current low coral cover in the MSSCA is largely a function of coral bleaching and disease, perhaps assisted by the components in dust blowing from Africa. Coral bleaching in the USVI is related to higher than normal water temperatures, which in turn is related to global climate change. Bleaching stresses corals and makes them more susceptible to disease (Miller et al 2006).
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LITERATURE CITED - CHAPTER 2 Adey, W.H., C.S. Rogers, R.S. Steneck and N.H. Salesky. 1981. The south St. Croix reef: A study of reef metabolism as related to environmental factors and an assessment of environmental management. Department of Conservation and Cultural Affairs, Government of the Virgin Islands. 74p. Adey, W.H., W. Gladfelter, J. Ogden and R. Dill. 1977. Field Guidebook to the reefs and reef communities of St. Croix, Virgin Islands. 3rd International Symposium on Coral Reefs. 52p. Geophysics GPR International, Inc. 2003. Marine Habitat Mapping Offshore St. Thomas & St. Croix US Virgin Islands EEZ, Final Report to the CFMC. Volume 2. pp. 21. Herzlieb, S., E. Kadison, J. Blondeau and R.S. Nemeth. 2006. Comparative assessment of coral reef systems located along the insular platform south of St. Thomas, US Virgin Islands and the relative effects of natural and human impacts. Proc 10th International Coral Reef Symposium 4-2:1144-1151. Kohler, K.E. and S.M. Gill. 2006. Coral Point Count with Excel extensions (CPCe): A Visual Basic program for the determination of coral and substrate coverage using random point count methodology. Computers Geosciences 32:1259-1269. Kojis, B.L. and N.J. Quinn. 2010. Validation of a Mutton Snapper (Lutjanus analis) spawning aggregation off St. Croix, U.S. Virgin Islands. Proceedings of the 62nd Gulf and Caribbean Fisheries Institute 62: 279-285. Miller, J., R. Waara, E. Muller and C.S. Rogers. 2006. Coral bleaching and disease combine to cause extensive mortality on reefs in U.S. Virgin Islands. Coral Reefs 25(3): 418-426. Smith, T.B., J. Blondeau, R.S. Nemeth, S.J. Pittman, J.M. Calnan, E. Kadison and J. Gass. 2009. Benthic structure and cryptic mortality in a Caribbean mesophotic coral reef bank system, the Hid Bank Marine Conservation District, U.S. Virgin Islands. Coral Reefs 29:289-308. Prada, M. 2003. Delineation of benthic habitats from side scan sonar mosaics from the Marine conservation District, St. Thomas, Lang Bank and Mutton Snapper Closed Area in St. Croix, U.S. Virgin Islands. Report to Caribbean Fishery Management Council, October 2003. Note: Side scan images depicting habitat types are taken from Prada 2003. pp 23. NOAA-NOS 2001. Benthic habits of Puerto Rico and the U.S. Virgin Islands, National Oceanic and Atmospheric Administration. Quinn, N.J. and B.L. Kojis. 1999. Subsurface seawater temperature variation and the recovery of corals from the 1993 coral bleaching event in waters off St Thomas, US Virgin Is. Bulletin of Marine Science 65(1):201-214. Quinn, N.J. and B.L. Kojis. 2003. Variation in subsurface seawater temperature off Discovery Bay, Jamaica and the U.S. Virgin Islands. International Journal of Tropical Biology & Conservation / Revista de Biología Tropical 51(4):181-187. Randall, J. 1963. An analysis of the fish populations of artificial and natural reefs in the Virgin Islands. Carib. J. Sci. 3:31-47. Randall, J. 1967. Food habits of the reef fishes of the West Indies. Studies in Tropical Ocean81
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ography, Inst. of Marine Sci., Univ. of Miami. 5:665-847. Rivera, J.A., M.C. Prada, J.-L. Arsenault, G. Moody and N. Benolt. 2005. Detecting fish aggregations from reef habitats mapped with high resolution side scan sonar imagery. NMFS PAP 5:88-104. website:http://www.sefsc.noaa.gov/sedar/download/S14RD11%20Rivera%20 Carib% 20Reef%20Sonar%202005.pdf?id=DOCUMENT Rothenberger, P., et al. 2008. The state of coral reef ecosystems of the U.S. Virgin Islands. NOAA Technical Memorandum NOS NCCOS 11. Silver Spring, MD. 522 pp. Sammarco, P., J. Leighton and J. Ogden. 1977. Grazing and control of coral reef community structure by Diadema antillarum Philippi (Echinodermata:Echinoides): a preliminary study. Journ. of Mar. Res. 32:47-53. Snyder, D.B. and G.H. Burgess. 2007. The Indo-Pacific red lionfish, Pterois volitans (Pisces: Scorpaenidae), new to Bahamian ichthyofauna. Coral Reefs 26:(1):175.
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APPENDICIES CHAPTER 2
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Appendix 1 - Abstract 63rd Gulf and Caribbean Fisheries Institute Meeting Age-frequency distributions of a protected mutton snapper (Lutjanus analis) aggregation following 17 years of protection LIAM CARR and BARBARA LOUISE KOJIS Snappers have historically been an important economic stock for the U.S. Virgin Islands, annually contributing nearly 4% of total landings by weight prior to seasonal closures set in place to prevent stock collapse. Evidence of depleted mutton snapper (Lutjanus analis) stocks in St. Croix led the Caribbean Fisheries Management Council into developing the Mutton Snapper Seasonal Area Enclosure (MSSAE) in 1993. The MSSAE closes fishing off at a historical fish spawning aggregation (FSA) site, during the March-June mutton snapper spawning season. Between March 2009 and June 2010, 139 mutton snapper were collaboratively harvested with St. Croix fishers within the MSSAE from an anchored fishing vessel at coordinates provided by local fishers. From this sample, 61 otoliths were collected and analyzed to develop agefrequency distributions, an important tool for creating growth curves and examining population structures. This analysis is part of the first effort since the MSSAE was enacted for gauging how successful management programs have been over the past 17 years for rebuilding local mutton snapper stocks. Researchers determined that the sampled population had a mean age of 6.5 ± 1.8 yrs, with a mode of 7 yrs. Additional analyses on length-frequency and weight-frequency distributions, along with examinations of gonadal conditions, provide preliminary evidence that the MSSAE’s historical FSA site remains active, although the size of the spawning population continues to be difficult to assess.
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Appendix 2 - Summary of Benthic Habitat Analysis: Benthic Categories Table A2-2.1 – Descriptive statistics of benthic categories by site in Algae and Invertebrates (ALIN) habitat. Transect Name Number of frames Total points MAJOR CATEGORY Coral Gorgonians Sponges Zoanthids Macro algae Turf algae Dead coral Coralline algae Diseased corals Sand, pavement, rubble Sum depth m
ALIN 1 100 2000 % of Transect 3.55 0.05 16.90 0.00 8.50 70.00 0.35 0.10 0.00
ALIN 2 ALIN 3 100 100 2000 2000 % of % of Transect Transect 0.25 4.10 0.00 0.05 5.00 3.90 0.00 0.05 28.25 27.05 11.00 62.95 0.25 0.05 1.25 0.05 0.00 0.00
ALIN 4 100 2000 % of Transect Mean 0.55 2.11 0.10 0.05 2.95 7.19 0.00 0.01 31.75 23.89 9.00 38.24 0.75 0.35 2.15 0.89 0.00 0.00
0.55
54.00
1.80
52.75
100.00
100.00
100.00
100.00
12.80
13.90
14.90
15.80
85
27.28
Std. Dev 1.99 0.04 6.53 0.03 10.45 32.74 0.29 1.01 0.00
Std. Error 1.00 0.02 3.26 0.01 5.23 16.37 0.15 0.50 0.00
30.15
15.07
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A2-2.2 – Descriptive statistics of benthic categories by site in Sand and Invertebrates (SAIN) habitat. TRANSECT NAME Number of frames Total points MAJOR CATEGORY Coral Gorgonians Sponges Zoanthids Macro algae Turf algae Dead coral Coralline algae Diseased corals Sand, pavement, rubble Sum depth m
SAIN 1 SAIN 2 SAIN 3 SAIN 4 Total 100 100 100 100 400 1600 1600 1600 1600 6400 % of % of % of % of Transect Transect Transect Transect Mean Std Dev. 2.25 4.30 2.10 0.55 2.30 1.54 0.00 0.80 1.10 0.00 0.48 0.56 6.05 11.50 7.40 2.90 6.96 3.56 0.00 0.00 0.00 0.00 0.00 0.00 9.05 17.75 6.60 55.30 22.18 22.60 82.10 6.85 1.05 28.70 29.68 36.92 0.10 0.50 8.30 0.00 2.23 4.06 0.10 0.05 0.15 0.00 0.08 0.06 0.00 0.00 0.15 0.00 0.04 0.08 0.35 58.25 73.15 12.55 36.08 35.10 100.00 100.00 100.00 100.00 13.40
13.70
86
22.30
13.90
Std. Error 0.77 0.28 1.78 0.00 11.30 18.46 2.03 0.03 0.04 17.55
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A2-2.3 - Descriptive statistics of benthic categories by site in Sand No Ripple (SANR) habitat. TRANSECT NAME Number of frames Total points Major Category Coral Gorgonians Sponges Zoanthids Macroalgae Turf algae / cyanobacteria Dead coral with algae Coralline algae Diseased corals Sand, pavement, rubble Sum depth m
SANR 1 SANR 2 100 100 2000 2000 % of % of transect transect 0.20 0.05 0.00 0.00 7.20 14.55 0.00 0.00 4.35 1.75
SANR 3 100 2000 % of transect 0.05 0.00 1.50 0.00 0.40
SANR 4 Total 100 400 2000 8000 % of transect Mean 0.35 0.16 0.00 0.00 2.35 6.40 0.00 0.00 13.25 4.94
Std. Dev. 0.14 0.00 5.99 0.00 5.78
Std. Error 0.07 0.00 2.99 0.00 2.89
27.10 0.05 0.00 0.00
30.00 0.00 0.00 0.00
2.20 8.15 0.05 0.30
32.35 0.35 0.35 0.05
22.91 2.14 0.10 0.09
13.97 4.01 0.17 0.14
6.99 2.01 0.08 0.07
61.10 100.00
53.65 100.00
87.35 100.00
50.95 100.00
63.26
16.62
8.31
29.90
25.60
21.30
13.70
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Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A2-2.4 – Descriptive statistics of benthic categories by site in Sparse Algae – (SPAL) habitat. TRANSECT NAME Number of frames Total points MAJOR CATEGORY Coral Gorgonians Sponges Zoanthids Macro algae Turf algae/cyanobacteria Dead coral Coralline algae Diseased corals Sand, pavement, rubble Sum depth m
SPAL 1 100 2000 % of transect 1.15 0.00 4.56 0.00 15.90 76.34 0.05 0.00 0.00 2.00 100.00
SPAL 2 100 2000 % of transect 0.55 0.00 2.55 0.00 23.55 5.55 0.70 0.25 0.00 66.85 100.00
11.00
15.24
88
Total 200 4000 Mean 0.85 0.00 3.55 0.00 19.73 40.94 0.38 0.13 0.00 34.43
Std. Dev. 0.42 0.00 1.42 0.00 5.41 50.06 0.46 0.18 0.00 45.86
Std. Error 0.30 0.00 1.00 0.00 3.82 35.39 0.32 0.13 0.00 32.42
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A2-2.5 – Descriptive statistics of benthic categories by site in Sand Ripple (SARI) habitat. TRANSECT NAME Number of frames Total points MAJOR CATEGORY Coral Gorgonians Sponges Zoanthids Macro algae Turf algae/cyanobacteria Dead coral Coralline algae Diseased corals Sand, pavement, rubble Sum depth m
SARI 100 2000 % of transect 0.30 0.00 1.65 0.00 1.25 14.70 0.00 0.00 0.00 82.10
100.00 11.00
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Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A2-2.6 – Descriptive statistics of benthic categories by site in Dense Algae (DEAL) habitat. TRANSECT NAME Number of frames Total points Major Category Coral Gorgonians Sponges Zoanthids Macroalgae Turf algae, cy bacteria Dead coral with algae Coralline algae Diseased corals Sand, pavement, rubble Sum Depth m
DEAL 1 100 2000 % of transect 0.05 0.00 2.45 0.00 2.40 10.95 0.00 0.00 0.00 84.15 100.00
DEAL 2 100 2000 % of transect 0.25 0.00 1.50 0.00 0.25 0.70 3.80 0.05 0.00 93.45 100.00
19.9
16.5
90
Total 200 4000 Mean 0.15 0.00 1.98 0.00 1.33 5.83 1.90 0.03 0.00 88.80
Std. 0.14 0.00 0.67 0.00 1.52 7.25 2.69 0.04 0.00 6.58
Std Error 0.10 0.00 0.48 0.00 1.08 5.13 1.90 0.03 0.00 4.65
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A2-2.7 - Descriptive statistics of benthic categories by site in Coral Patch (COPA) habitat. TRANSECT NAME Number of frames Total points MAJOR CATEGORY Coral Gorgonians Sponges Zoanthids Macro algae Turf algae Dead coral Coralline algae Diseased corals Sand, pavement, rubble Sum depth m
COPA 3 20 400 % of Transect 5.25 0.75 6.80 0.00 33.90 2.25 36.35 7.90 0.00 6.80 100.00 21.3
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Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A2-2.8 - Descriptive statistics of benthic categories by site in Coral Limestone (COLI) habitat. TRANSECT NAME COLI 1 COLI 2 COLI 3 COLI 4 COLI 5 Number of frames 20 20 20 20 20 Total points 400 400 400 400 400 MAJOR % of % of % of % of % of CATEGORY transect transect transect transect transect Coral 5.46 7.45 9.90 8.25 6.75 Gorgonians 2.00 2.65 8.20 1.75 4.75 Sponges 18.38 15.50 6.30 21.05 19.75 Zoanthids 0.04 0.00 0.20 0.00 0.00 Macro algae 28.75 35.15 17.40 25.25 24.25 Turf algae / cyanobacteria 34.83 22.00 2.00 11.60 34.50 Dead coral 0.13 7.25 51.75 24.45 0.00 Coralline algae 0.00 9.45 2.30 5.00 0.00 Diseased corals 0.04 0.05 0.40 0.05 0.00 Sand, pavement, rubble 10.38 0.50 1.55 2.60 10.00 Sum 100.00 100.00 100.00 100.00 100.00 depth m
17.10
25.60
22.60
92
19.80
22.50
Total 100 2000 Std. Dev. 1.66 2.69 5.90 0.09 6.50
Std Error 0.74 1.20 2.64 0.04 2.90
20.99 14.35 16.72 21.97 3.35 3.98 0.11 0.16
6.42 9.83 1.78 0.07
5.01
2.14
Mean 7.56 3.87 16.20 0.05 26.16
4.79
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A2-2.9 - Descriptive statistics of benthic categories by site in Gorgonian Plain (GOPL) habitat. TRANSECT NAME Number of frames Total points MAJOR CATEGORY Coral Gorgonians Sponges Zoanthids Macro algae Turf algae / cyanobacteria Dead coral Coralline algae Diseased corals Sand, pavement, rubble Sum depth m
GOPL 1 GOPL 2 GOPL 3 GOPL 4 Total 100 100 100 100 400 2000 2000 2000 2000 8000 % of % of % of % of transect transect transect transect Mean 5.85 5.15 5.30 11.70 7.00 1.80 3.30 2.60 6.00 3.43 10.05 11.55 17.20 12.15 12.74 0.00 0.00 0.00 0.00 0.00 17.55 4.95 8.80 39.45 17.69
Std. Dev 3.15 1.82 3.10 0.00 15.44
Std. Error 1.57 0.91 1.55 0.00 7.72
35.20 0.10 0.00 0.00
9.00 12.20 0.90 0.15
12.05 11.90 0.00 0.05
3.15 17.40 5.75 0.00
14.85 10.40 1.66 0.05
14.06 7.32 2.76 0.07
7.03 3.66 1.38 0.04
29.45 100.00
52.80 100.00
42.10 100.00
4.40 100.00
32.19
20.84
10.42
16.2
13.70
12.20
31.6
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Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Appendix 3 - Summary of Benthic Habitat Analysis: Coral Species Table A2-3.1 - Mean percent cover of coral species (+SE) (N=5) in the COLI habitat. Species are listed in order of abundance. Mean % Cover 2.71 1.24 1.14 0.75 0.48 0.23 0.16 0.14 0.06 0.06 0.05 0.03 0.02 0.02 0.01 0.01 0.01
Montastrea annularis Porites astreoides Montastrea cavernosa Millepora alcicornis Siderastrea siderea Porites porites Meandrina meandrites Acropora cervicornis Agaricia agaricites Colpophyllia natans Eusimilia fastigiata Diploria strigosa Madracis mirabilis Stephanocoenia michelini Diploria labyrinthiformis Porites divaricata Scolymia cubensis
SE 0.84 1.21 0.73 0.52 0.33 0.16 0.09 0.09 0.05 0.04 0.03 0.02 0.02 0.02 0.01 0.01 0.01
Table A2-3.2 - Mean percent cover of gorgonian genera (+SE) (N=5) in the COLI habitat. Genera are listed in order of abundance.
Pseudopterogorgia Muricea Eunicea Plexaurella Pseudoplexaura Gorgonian Briareum Pterogorgia Plexaura
Mean % Cover 1.59 0.60 0.34 0.27 0.18 0.10 0.02 0.02 0.01
94
SE 0.41 0.14 0.24 0.15 0.03 0.10 0.02 0.02 0.01
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A2-3.3 - Mean percent cover of algal genera (+SE) (N=5 in the COLI habitat. Genera are listed in order of abundance.
Lobophora Wrangelia Dictyota Halimeda Amphiroa Sargassum
Mean % Cover 21.63 1.72 0.79 0.26 0.02 0.02
SE 1.76 1.72 0.21 0.07 0.01 0.02
Table A2-3.4 - Mean percent cover of coral species (+SE) (N=4) in the GOPL habitat. Species are listed in order of abundance. Mean % Cover 8.75 4.40 3.90 3.00 2.70 2.25 0.75 0.60 0.55 0.15 0.15 0.15 0.15 0.15 0.10 0.10 0.05 0.05 0.05
Montastrea annularis Millepora alcicornis Siderastrea siderea Montastrea cavernosa Montastrea faveolata Porites astreoides Meandrina meandrites Agaricia agaricites Diploria strigosa Porites porites Colpophyllia natans Mycetophyllia danaana Mycetophyllia ferox Porites divaricata Dichocoenia stokesii Madracis mirabilis Colpophyllia natans Diploria clivosa Stephanocoenia michelini
95
SE 3.26 1.23 1.22 1.44 2.40 1.23 0.57 0.49 0.55 0.15 0.06 0.15 0.15 0.10 0.10 0.06 0.05 0.05 0.05
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A2-3.5 - Mean percent cover of gorgonian genera (+SE) (N=4) in the GOPL habitat. Genera are listed in order of abundance.
Pseudopterogorgia Plexaurella Eunicea Gorgonian Muricea Pseudoplexaura Briareum Pterogorgia
Mean % Cover 1.43 1.38 0.25 0.14 0.14 0.08 0.01 0.01
SE 0.61 0.51 0.15 0.14 0.08 0.06 0.01 0.01
Table A2-3.6 - Mean percent cover of coral species (+SE) (N=4) in the ALIN habitat. Species are listed in order of abundance. Mean % Cover 0.96 0.34 0.31 0.21 0.13 0.10 0.05 0.03 0.03 0.03 0.01
Siderastrea siderea Montastrea cavernosa Millepora alcicornis Montastrea annularis Porites astreoides Stephanocoenia michelini Meandrina meandrites Diploria labyrinthiformis Porites divaricata Porites porites Eusimilia fastigiata
96
SE 0.35 0.19 0.10 0.16 0.08 0.05 0.04 0.02 0.03 0.03 0.01
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A2-3.7 - Mean percent cover of algal genera (+SE) (N=4) in the ALIN habitat. Genera are listed in order of abundance.
Sargassum Lobophora Dictyota Amphiroa Halimeda Padina Schizothrix
Mean % Cover 11.74 6.68 4.41 0.74 0.09 0.03 0.03
SE 1.83 1.47 0.88 0.07 0.04 0.03 0.02
Table A2-3.8 - Mean percent cover of coral species (+SE) (N=4) in the SAIN habitat. Species are listed in order of abundance. Mean % Cover 0.68 0.54 0.45 0.14 0.10 0.09 0.08 0.05 0.04 0.03 0.03 0.03 0.03 0.01 0.01 0.01 0.01
Siderastrea siderea Millepora alcicornis Montastrea cavernosa Porites astreoides Montastrea annularis Meandrina meandrites Colpophyllia natans Diploria labyrinthiformis Colpophyllia natans Dichocoenia stokesii Diploria strigosa Madracis mirabilis Porites porites Eusimilia fastigiata Millepora squarrosa Scolymia cubensis Stephanocoenia michelini
97
SE 0.24 0.18 0.32 0.07 0.09 0.08 0.05 0.05 0.02 0.02 0.03 0.03 0.03 0.01 0.01 0.01 0.01
Chapter 2: Habitat Description of the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A2-3.9 - Mean percent cover of algal genera (+SE) (N=4) in the SAIN. Genera are listed in order of abundance.
Dictyota Lobophora Wrangelia Turbinaria Sargassum Halimeda Liagora Schizothrix
Mean % Cover 10.98 7.16 3.66 0.13 0.11 0.11 0.01 0.01
98
SE 1.19 1.60 2.20 0.05 0.09 0.07 0.01 0.01
Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
CHAPTER 3 Habitat Focused Fish Surveys in the Mutton Snapper Seasonal Closed Area
INTRODUCTION The Mutton Snapper Seasonal Closed Area (MSSCA) was initially created to protect a Lutjanus analis (mutton snapper) spawning aggregation during the known spawning season by prohibiting fishing in the MSSCA for four months of the year (March 1 - June 30). Subsequently, with the approval of the SFA Amendment (CFMC and NMFS 2005), which amended the Spiny Lobster and Reef Fish Fishery Management Plans in 2005, all bottom tended gear, including bottom long lines, gill and trammel nets, and pots or traps, was prohibited on coral or hard bottom habitat within the MSSCA year round (50 CFR 622.33). The latter regulatory provision was adopted to protect essential fish habitat (EFH). EFH is defined in the Magnuson-Stevens Act as "those waters and substrate necessary for spawning, breeding, feeding or growth to maturity" (CFMC 1998). The MSSCA met the criteria for EFH because it was presumed to contain habitat necessary for the spawning and breeding of the mutton snapper (Lutjanus analis) and, likely, other species of fish as well. In order to characterize the distribution and abundance of fish species within the habitats identified by Prada (2003) in the MSSCA, roving fish and fish transect surveys were conducted in each habitat. Also, the presence and life stage (juvenile, subadult and adult) of mutton snapper were recorded.
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Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
MATERIALS AND METHODS Fish surveys were conducted in eight of the nine the benthic habitats identified by Prada (2003). One habitat, COPA (Coral Patch), comprising < 5 ha total area within the MSSCA could not be uniquely identified. Chapter 2 of this study characterizes these habitats. Habitat was identified using Prada's habitat maps created in Arc View GIS. Latitude and longitude coordinates for specific habitat sites identified by the authors were provided by Jeremiah Blondeau of the University of the Virgin Islands using Prada habitat map database and Arc View GIS. The number of sites surveyed in each habitat was a function of the abundance of that habitat within the MSSCA (see Chapter 2 of this study). To ensure that divers were conducting fish surveys in the identified habitat, a Garmin WAAS enabled GPSmap 76Cx was used to locate habitats based on habitat locations on Prada's habitat maps and coordinates provided by Blondeau. When the specified coordinates were located using the GPS, a weight with dive flag attached to a rope was dropped from the boat to mark the habitat. Roving fish surveys and fish transect surveys were all carried out in the vicinity of the marked area. Most surveys were carried out in the morning between 7:00 and 11:00 am in June and July 2009. A few surveys were conducted in 2010 during May and June in mid-afternoon from about 2:30 - 5:00 pm. Note: Common names for fish in the following text, tables and appendices are based on Humann (undated). Fish and Caribbean Spiny Lobster and Queen Conch Transects At each site, a total of five 20m transects were laid haphazardly on the substrate within the habitat to record benthos (see Chapter 2) and fish populations within specific habitat types. A total area of 400m2 was surveyed for fish at each site. One to four sites were surveyed for each habitat type. More sites were surveyed in habitats comprising more of the area of the MSSCA. All fish two meters each side of each transect were identified to species and numbers of individuals counted. The recording diver stopped every five meters along the transect line and recorded the fish observed. Most blennies, gobies, and other very small fish were not recorded. Most of these species are cryptic and it would have been time consuming and difficult to accurately count them. Fish census surveys were primarily conducted by Dr. Barbara Kojis. Counts of Acanthurus bahianus (ocean surgeonfish) and A. chirurgus (doctorfish) in both transects and roving fish surveys (see below) were combined because the two species are primarily distinguished underwater by the presence of body bars in A. chirurgus. However, these bars can be "quite faint" according to Humann ( undated). Acanthurids with bars were seldom seen during transects. Because A. chirurgus is commonly seen in fishers catches (A. chirugus body bars were clearly seen in dead surgeonfish in fisher's coolers), we suspected that A. chirurgus was not being accurately counted underwater. Lobsters (Panulirus argus) were also recorded in transects. Lobsters are found under ledges and in crevasses. They can be difficult to find unless a concerted effort is made to look in every crack and crevasse. Given the limited bottom time, especially in deeper sites, and the large 100
Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
number holes in COLI (Coral Limestone - deepwater coral reef habitat), P. argus presence and abundance in most habitats is likely under-represented in this study. Roving Fish Censuses At each site, one to three roving fish counts were conducted for 15 minutes. When more than one fish count was conducted at a site, they were usually done on different days. Divers swam in a slow steady fashion around an imaginary outer circumference of the study site and in the vicinity of the site marker, recording species and number of fish observed. Divers were instructed to record fishes within the marked habitat. However, this was difficult for habitat characterized by small sand patches such as SARI (see Chapter 2) or sand channels surrounded by COLI and GOPL habitats (see Chapter 2) and bisected by limestone/coral "bridges", which served as super highways for fish, e.g. SANR habitat. Divers were also instructed not to count small species in the roving fish censuses, (i.e. blennies, gobies, pomacentrids, small species of pufferfish, and all wrasses except the three larger wrasses listed in the CFMC reef fish FMP: puddingwife (Halichoeres radiatus), hogfish (Lachnolaimus maximus) and Spanish hogfish (Bodianus rufus). When schools of fish were encountered, the number of fish in the school was estimated. Roving fish censuses were conducted primarily by Liam Carr, Texas A&M University, and Gerson Martinez, commercial fisher, St. Croix. Fish Biodiversity Habitat biodiversity was compared using the Shannon Diversity Index (H'). H' takes into account the number of species and the evenness (relative abundance) of the species. Values increase when there are more unique species or the numbers of individuals of each species are similar (greater evenness).
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Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
RESULTS A total of 132 species (not including species only identified to family or genus unless it was clear that the species was unique, e.g. only species recorded in family or genus) and 24,225 individual fish were recorded (Tables A3-1.1 and A3.1.2) . Of these 21,564 individual fish were included in analyses (see Materials and Methods for rationale): 107 species and 13,417 individuals (Table 3.1) in benthic transects and 87 species and 8,147 individuals in roving fish surveys (Table 3.2). Most of the species removed from the analyses were species inconsistently recorded in the roving fish survey (small wrasses, damselfish, etc.) and, therefore, omitted so that comparisons could be more accurately made between habitats. The mean number of species per site and individuals 100m-2 in each habitat for the benthic transect method ranged from 16 - 31.6 and 42 - 176.9, respectively (Table 3.1). Only one lionfish (Pterois volitans) was observed (in July 2010) in the MSSCA in over 250 diver hours from April 2009 to July 2010. In the transect surveys Coral Limestone (COLI) and Gorgonian Plain (GOPL) had the most species and individuals in the benthic transect surveys with an average of 31.6 and 26.5 species per site and 176.9 and 170.4 individuals 100m-2 (Table 3.1), respectively. Sand Ripple (SARI) had the fewest species and individuals 100m-2. Dense Algae (DEAL - hard bottom with some sand) had the greatest biodiversity (H') and SAIN (Sand with Invertebrates - hard bottom with some sand) had the least. The Coral Patch (COPA) habitat identified by Prada (2003) was not recognized in situ (see Chapter 2) and will not be considered in the subsequent analysis. Table 3.1. Summary of fish transect data in the Mutton Snapper Seasonal Closed Area. Prada (2003) habitat types in column headers are described in Chapter 2. ALIN
COLI
DEAL
GOPL
SAIN
SANR
Total # individuals
2406
3537
478
2726
2315
809
168
978
# individuals 100m-2
150.4
176.9
59.8
170.4
144.7
50.6
42.0
122.3
39
61
29
52
42
42
16
29
1
18.3
31.6
19.5
26.5
19.5
19.3
16
21
Shannon Diversity Index (H')
2.41
3.16
3.45
3.11
2.20
3.26
2.40
2.95
# Lobster
1
2
0
0
0
0
0
0
Number of sites surveyed
4
5
2
4
4
4
1
2
Total # species Mean # species site-
SARI SPAL
In the roving fish surveys (Table 3.2), DEAL had the highest mean number of individuals recorded, owing to two schools of scads recorded by surveyors. COLI had the highest mean number of species and biodiversity (H') (Table 3.2). SANR had the lowest mean number of individuals and the second lowest number of species after ALIN. SANR is primarily a sand
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Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
habitat with coral rubble around its periphery. ALIN is a flat, pavement habitat with algae and scattered macro-invertebrates. Lobsters were very rare and were only present in Algae Invertebrates (ALIN) and Coral Limestone (COLI) (Table 3.1). However, as noted above, lobsters are cryptic and the focus of the surveys was fish species. Intensive searches in cracks and crevasses (lobster habitat) were not conducted. It is likely that lobsters, especially juvenile lobsters, are present in the hard bottom habitats (DEAL, GOPL, SARI, SPAL), which have cracks, crevasses, and ledges, preferred by juvenile and adult lobsters, as well as sponges and algae covered coral heads preferred by newly settled lobsters. Table 3.2. Summary of roving fish surveys in the Mutton Snapper Seasonal Closed Area. Prada (2003) habitat types in column headers are described in Chapter 2.
Total # individuals Mean # individuals survey-1 (SD)
ALIN
COLI
DEAL
GOPL
SAIN
SANR
SARI
SPAL
1233
1489
1064
1302
1028
820
200
1011
176.10 (119.08)
186.61 354.67 217.00 205.6 102.50 252.75 200.0 (52.64) (288.70) (145.77) (97.88) (60.08) (271.22)
Total # species
34
57
29
43
38
43
17
27
Mean # species survey -1 (SD) # roving surveys Shannon Diversity Index (H')
12.28 (3.20)
23.0 (3.2)
18.67 (2.52)
17.83 (5.42)
17.80 (4.97)
14.50 (3.29)
17
12.75 (4.57)
7
8
3
6
5
8
1
4
3.20
4.19
3.53
3.71
3.65
3.79
3.05
2.46
Habitat Overview Using the Agglomerative Hierarchical Clustering (XLSTAT 2010) analysis of the fish species recorded in transects by habitat (fish abundance was standardized by 100m-2 and only species comprising >1% of total were included), we correlated the fish with habitats using Pearson correlation coefficients and then agglomerated the habitats using weighted pair-group averages, which resulted in the clusters shown in Figure 3.1. At the 0.80 similarity level there are three major clusters. The first cluster is coral reef on consolidated sediments (COLI, GOPL) characterized primarily by the presence or absence of parrotfishes: princess, striped and stoplight; the black durgon; French grunt; blackbar soldierfish; and blue chromis. The second cluster is comprised of ALIN, SPAL and SAIN, which were flat pavement habitats (SAV on consolidated sediments), are characterized primarily by the yellowhead wrasse, spotted goatfish, bridled goby, slippery dick, bicolor damselfish, queen triggerfish, sand tilefish, and yellowhead jawfish. SANR, DEAL and SARI, the third cluster comprise two unconsolidated sediment habitats (SANR and SARI) and DEAL, which is more of a consolidated sediment habitat but has 103
Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
pockets of deep sand. Fish characterizing these habitats primarily include the bluehead wrasse, coney, longspine squirrelfish, squirrelfish, three species of surgeonfish, brown chromis, banded butterfly fish, redband parrotfish, foureye butterfly fish and rock beauty.
0.66 0.71
Similarity
0.76 0.81 0.86 0.91
SANR
DEAL
SARI
SAIN
ALIN
SPAL
GOPL
COLI
0.96
Figure 3.1. Dendrogram of habitats using Agglomerative Hierarchical Clustering (XLSTAT 2010). Pearson correlation coefficients were used to correlate fish species distribution and abundance with habitat and habitats were agglomerated using weighted pair-group averages. The dotted line divides the habitats into three major clusters at 0.80 similarity. Habitat Summaries ALIN - Algae Invertebrates ALIN is a hard bottom habitat with sponges and small to medium sized coral heads, which are mostly dead and covered in macroalgae and small sessile invertebrates, and some gorgonians. Crevasses and shallow solution holes partially filled with sand and coral rubble were distributed throughout the habitat and, along with the larger invertebrates, provide shelter for small and medium sized fish.
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Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Fish Surveys – Transects A variety of small wrasses, pomacentrids, and serranids were recorded in transects in ALIN habitat (Appendices Chapter 3 (A3) Table A3-1.1). Two species, Thalassoma bifasciatum (bluehead wrasse) and Eupomacentrus partitus (bicolor damsel fish), comprised a total of 75.4% of the fish recorded in this habitat using transect methodology (Table A3-2.1). Only a few species targeted by fishers were recorded in transects in this habitat. These were primarily grazers (ocean/doctor surgeonfish (comprising 1.9% of individuals recorded), redband parrotfish) (0.7%), princess parrotfish (0.2%), redtail parrotfish (<0.1%), yellowtail parrotfish (<0.1%)), the longspine squirrelfish (1.9%), and a pelagic baitfish, the round scad, locally known as "round robin" (4.2%). Only two predator species targeted by fishers, the coney (0.8%) and barracuda (<0.1%) were recorded. Roving Fish Census A total of 32 species and 1,234 individuals were recorded in the four sites surveyed (Table A32.2). The schooling Decapterus punctatus (25.1% of individuals recorded) was the most abundant fish observed in the roving censuses (Table A3-2.1). Doctor/ocean surgeon fish were the second most abundant species comprising 22% of individuals recorded. Twenty-three species targeted by fishers were recorded, including surgeonfish, parrotfish, angelfish, squirrelfish, queen triggerfish, barracuda, filefish, goatfish, and trunkfish. Eight species, seven of which were commercial fisheries species, comprised almost 90% of the individuals recorded. One large mutton snapper was recorded. COLI - Coral Limestone This habitat is comprised of primarily dead, algae covered coral forming spurs and groove reefs (see Chapter 2). These reefs were historically dominated by corals, particularly the Montastrea annularis species complex. The habitat was still structurally complex and had the highest mean number of fish species and individuals per 100m-2 in the transect surveys (Table 3.1) and the highest mean number of species and highest biodiversity (H') in the roving surveys (Table 3.2). Sixty-one species of fish were recorded in the transect surveys and 57 in the roving surveys. Fish Surveys – Transects Blue chromis (Chromis cyanea), (32.57%), bluehead wrasse (Thalassoma bifasciatum) (24.77%) and bicolor damselfish (Eupomacentrus partitus) (11.70%) comprised almost 70% the fish recorded in COLI transects (69.04%) (Table A3-2.3). The princess parrotfish (Scarus taeniopterus) was the most abundant commercial species (6.33% of total). Nine species, of which three were commercial species, comprised almost 90% of the individuals recorded. Roving Fish Census The black durgon (Melichthys niger) (16.52%), princess parrotfish (Scarus taeniopterus) (16.45%) and ocean/doctor surgeonfish (Acanthurus chirurgus/bahianus) were the most abundant fish in the roving census, comprising 44.53% of the total (Table A3-2.4) Seventeen species made up almost 90% of the individuals recorded, At least 14 of which are marketable fish on St. Croix. Among the species comprising the 90% were two groupers, the small coney 105
Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
(Cephalopholis fulvus - 3.63% of individuals recorded) and graysby (Epinephelus cruentatus 1.81%), and one snapper, the mahogany snapper (Lutjanus mahogoni - 1.75%). Two mutton snapper (L. analis) were recorded comprising 0.13% of fish recorded in a total of 8 roving surveys conducted in this habitat. DEAL - Dense Algae DEAL is a hard bottom habitat with primarily a thin layer of sand with macroalgae and scattered invertebrates. It has deeper, coral rubble filled, sand pockets in depressions scattered throughout the habitat. The larger invertebrates (coral heads, sponges, and gorgonians), crevasses, ledges and depressions provide habitat for small fish and limited habitat for larger species. Fish Surveys – Transects Nine species made up 90% of the fish recorded (Table A3-2.5) in this habitat. Only two were marketable fish: Caranx ruber and the baitfish Decapterus punctatus comprising 10.67% and 10.46% of the recorded fish, respectively. The ubiquitous bicolor damselfish was the most abundant comprising 27.82% of fish recorded. The sand burrowing yellowhead jawfish, Opistognathus aurifrons was the second most abundant species comprising 15.27%. Its high relative abundance indicated that this habitat had extensive areas of deeper sand, even though it is primarily a hard bottom habitat. DEAL had the highest biodiversity (H' = 3.45) (Tables 3.1 and A3-2.5). Roving Fish Census The French grunt, Haemulon flavolineatum (20.43%), black durgon, Melichthys niger (19.77%), doctor/ocean surgeonfish, Acanthurus chirurgus/bahianus (15.63%), and coney, Cephalopholis fulvus (7.06%), comprised 62.90% of the fish recorded (Table A3-2.6). A total of 25 commercially marketable species were recorded, including seven species of parrotfish, which comprised 10.44% of the fish recorded (Table A3-2.6). GOPL - Gorgonian Plain Fish Surveys – Transects The ubiquitous bluehead wrasse, Thalassoma bifasciatum, and bicolor damselfish, Eupomacentrus partitus, comprised more than half the fish recorded in the benthic transects in the GOPL habitat (Table A3-2.7). Ten species comprised nearly 90% of the individuals recorded. Of these three were species that are commercially caught on St. Croix: doctor/ocean surgeonfish, Acanthurus chirurgus/bahianus (5.10% of individuals recorded); princess parrotfish, Scarus taeniopterus (3.74%); and coney, Cephalopholis fulvus (1.39%). Roving Fish Census Acanthurus chirurgus/bahianus was the most abundant fish (25.04% of individuals recorded) of the 43 species recorded in the six roving surveys in GOPL (Table A3-2.8). The black durgon, Melichthys niger (19.82%), and the coney, Cephalopholis fulvus (7.3%), were the next most abundance species. These three species comprise more than half the individual fish counted.
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Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Twelve species make up nearly 90% of individual fish counted and include ten commercially harvested species. SAIN - Sand Invertebrates SAIN is flat, hard bottom habitat with a layer of sand and algae with scattered invertebrates (live and dead coral heads, sponges, and a few gorgonians). This habitat does not support large numbers of commercial fisheries species. Fish Surveys – Transects Thalassoma bifasciatum (56.72%) was overwhelmingly the most abundant fish in these surveys. Eupomacentrus partitus (23.11%) was next most abundant and together with T. bifasciatum comprised 79.83% of the benthic survey total (Table A3-2.9). Roving Fish Census A total of 809 individuals and 42 species were observed in the roving survey (Table A3-2.10). The ocean/doctor surgeonfish, Acanthurus chirurgus/bahianus (31.23%),, black durgon, Melichthys niger (13.13%), French grunt, Haemulon flavolineatum (9.73%) comprised more than 50% of individuals counted in the roving fish censuses. Fourteen species comprised almost 90% of the individual fish recorded and included ten commercially important species (two of the smaller parrotfish species, three species of surgeonfish, the French grunt, the queen triggerfish, and two species of squirrelfish). SANR - Sand No Ripple SANR habitat is positioned between GOPL and COLI habitats. It is a deep sand habitat with coral rubble on its margins. Sand dwelling fish and small fish sheltering in and around coral rubble are the main resident species. Individuals and schools of larger species live on the periphery of the habitat, migrate along the edges of the habitat, and cross the habitat primarily where "bridges" of coral bisect the habitat. Fish Surveys – Transects The bluehead wrasse, Thalassoma bifasciatum (30.53%) and Eupomacentrus partitus (25.09%) comprised more than 50% of the individual fish recorded (Table A3-2.11). Ten species comprised nearly 90% of the individual fish recorded. Small wrasses, damselfish, jawfish, and gobies comprising nearly 83% of individual fish in the top ten species. Roving Fish Census Roving divers generally recorded and counted fish species not only in SANR habitat but also those that were associated with adjacent habitats (usually COLI and/or GOPL). In one case, the SANR sand channel was crossed by a raised carbonate "bridge" with corals, sponges, and gorgonians. These bridges are used as highways by fish (Gerson Martinez, pers. com.). Smaller fish, e.g. parrotfish, are known by fishers to avoid swimming over sand channels (SANR) to
107
Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
move from one habitat to the next or to migrate on to the shelf during the day and off the shelf at night. The diver recorded the fish streaming over the bridge. The ocean/doctor surgeonfish, Acanthurus chirurgus/bahianus (30.37%), coney, Cephalopholis fulvus (9.51), and scad, Decapterus sp. (8.54%), all commercially marketable fish, were the most abundant fish in the roving fish censuses, comprising 48.41% of the 820 individuals recorded (Table A3-2.12). SARI - Sand Ripple This is a minor habitat in the MSSCA comprising only 0.4 ha. It is a shallow water (13 - 15m depth) SANR type of habitat with sand channels lying between low rises of GOPL habitat, almost like the grooves of an old spur and groove reef system. The relative shallowness of the habitat means that it is more susceptible to wave action than SANR resulting in sand ripples when seas are heavy. Coral rubble, primarily dead branches of Acropora cervicornis, are scattered on the sand within the habitat. Fish Surveys – Transects When SARI habitat and fish populations were surveyed using transects, only one or two transects could be conducted in each SARI "groove" because of the limited size of the SARI habitat at the site surveyed. Thalassoma bifasciatum (53.57%), Eupomacentrus partitus (14.29%) and Opistognathus aurifrons (10.71%) comprised 78.57% of the 168 individuals in these surveys (Table A3-2.13). Eight commercially marketed species were recorded, but they comprised a total of only 22 of the total individuals recorded. This site had a low biodiversity (H' - 2.40) and lowest number of individuals 100m-2. Roving Fish Census Only one roving fish census was conducted in this habitat. Because of the small size of the SARI habitat patches, divers inevitably incorporated fish inhabiting both SARI and the adjacent lowrise GOPL habitat in their censuses. Acanthurus chirurgus/bahianus (27.50%), Melichthys niger (25.50%) and Holocentrus sp. (9.50%) collectively comprised 62.50% of the roving fish census (Table A3-2.14). This was the least diverse habitat with Shannon Diversity Index of 3.05 (Tables 3.2 and A3-2.14) with only seven species comprising almost 90% of the individual fish recorded. SPAL - Sparse Algae SPAL is a hard bottom habitat with a thin covering of sand and algae. Like the other hard bottom habitats in the MSSCA it contains cracks, crevasses and depressions and widely scattered invertebrates (dead and live coral heads and sponges), which provide habitat, primarily for small species of fish and the juveniles of some larger species. Fish Surveys – Transects Eight species comprised just over 90% of individual fish recorded. Six of these were small parrotfish, wrasses and damselfish (Table A3-2.15). The other two species were the doctor/ocean surgeon (Acanthurus chirurgus/bahianus) and the redband parrotfish (Sparisoma 108
Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
aurofrenatum), which together comprised 6.54% of fish recorded. A total of eight of 29 species recorded, were commercially marketable species. Roving Fish Census Six species, all commercially marketable, comprised 90.77% of the individual fish recorded in this habitat (Table A3-2.16). The round scad, Decapterus punctatus) comprised 54.40% of individuals recorded. The other five species included three acanthurid species (two are combined in this study), the longspine squrrelfish, H. rufus, (10.68%), the French grunt, H. flavolineatum, (12.96%) and the redband parrotfish, S. aurofrenatum (3.26%). A total of twenty-two marketable species were recorded in this habitat. Population Abundance of Marketable Fish Marketable fish (MF) is defined in this study as fish commonly recognized as commercially saleable fish on St. Croix, U.S. Virgin Islands. Determination of MF was obtained from a list of port samples (McCarthy and Gedamke, 2009), a list of fishes retained in bycatch studies carried out by MRAG on St. Croix (Anon. 2009), and from discussions with St. Croix fishers (Martinez and Dailey pers. com.) (Table 3.3). Species that can be consumed, i.e. small pomacentrids and chaetodons, have been excluded from the analysis because they are not considered marketable because of their small size. Black durgon were omitted because the meat is considered tough and this species is seldom marketed. Creole-fish (Paranthias furcifer), Saragassum triggerfish (Xanthichthys ringens) and sand tile fish (Malacanthus plumieri) were also omitted because they are not commonly targeted on St. Croix. The estimated relative abundance of the MF species in each family was calculated for each habitat using the benthic transect data (Table 3.4). Species in the five families, Acanthuridae (surgeonfishes) (30.88% - three MF), Carangidae (jacks and scads, 19.39% - four MF), Holocentridae (squirrelfishes) (17.20% - three MF), Scaridae (parrotfishes) (18.59% - seven MF), and Serranidae (7.72% - five MF).had the greatest estimated relative abundance totaling 93.79% of the MF families (Tables 3.3 and 3.5). The high relative abundance of groupers was a function of the high abundance of the coney (Cephalopholis fulvus) in most habitats. Lutjanids (six MF species - including Lutjanus analis) were not common and comprised only 0.13% of the MF species in the MSSCA (Table 3.5). Fish were relatively more abundant (ratio of % fish to % habitat: >1) in rugose habitats (COLI and GOPL) than in the less rugose hard bottom and sand habitats (Table 3.5). The relative proportion of fish in most of the flat, hard bottom habitats was 0.74 - 0.94 (ALIN, DEAL, SAIN, and SPAL). The two unconsolidated sediment habitats (SANR and SARI) had relatively few fish (ratio of fish to habitat <0.33).
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Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table 3.3: List of the species recorded in this study that are marketable fish species on St. Croix. The determination of marketable species on St. Croix was based on advice of St. Croix fishers Gerson Martinez and Tom Daley, a list of species caught and retained by fishers on St. Croix (Table 14 in Anon. 2009) and a list of fishes with >300 individuals recorded from commercial port samples taken on St. Croix (McCarthy and Gedamke 2009). Family Acanthuridae Acanthuridae Balistidae Balistidae Carangidae Carangidae Carangidae Carangidae Ephippidae Haemulidae Haemulidae Haemulidae Haemulidae Haemulidae Haemulidae Holocentridae Holocentridae Holocentridae Labridae Labridae Lutjanidae Lutjanidae Lutjanidae Lutjanidae Lutjanidae Lutjanidae Monacanthidae Monacanthidae Monacanthidae
Scientific Name Acanthurus coeruleus Acanthurus bahianus and A. chirurgus Balistes vetula Canthidermis sufflamen Caranx crysos Caranx ruber Decapterus punctatus Decapterus sp. Chaetodipterus faber Anisotremus virginicus Haemulon carbonarium Haemulon aurolineatum Haemulon flavolineatum Haemulon plumieri Haemulon sciurus Holocentrus adscensionis Holocentrus rufus Myripristis jacobus Bodianus rufus Halichoeres radiatus Lutjanus analis Lutjanus apodus Lutjanus mahogoni Lutjanus synagris Ocyurus chrysurus Rhomboplites aurorubens Aluterus scriptus Cantherhines macrocerus Cantherhines pullus
Common Name Blue Tang Surgeon - Doctor and Ocean Queen triggerfish2 Ocean triggerfish Blue runner Bar jack3 Round scad (Round robin) Scad Atlantic spadefish Porkfish Caesar grunt Tomtate French grunt White grunt Bluestriped grunt Squirrelfish Longspine squirrelfish Blackbar soldierfish2 Spanish hogfish2 Puddingwife (doesn't sell well) Mutton snapper2 Schoolmaster snapper2 Mahogany snapper2 Lane snapper Yellowtail snapper Vermillion snapper Scrawled filefish5 Whitespotted filefish5 Orangespotted filefish4,5
110
CFMC FMP Unit1 Surgeonfishes Unit Surgeonfishes Unit Triggerfishes Unit Triggerfishes Unit Jacks Unit Jacks Unit
Grunts Unit Grunts Unit Grunts Unit4 Grunts Unit Grunts Unit Grunts Unit Squirrelfishes Unit Squirrelfishes Unit Squirrelfishes Unit Wrasses Unit Wrasses Unit Snapper Unit 3 Snapper Unit 3 Snapper Unit 3 Snapper Unit 3 Snapper Unit 4 Snapper Unit 1 Filefish Unit Filefish Unit
Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Scientific Name Common Name CFMC FMP Unit1 Mullidae Mulloidichthys martinicus Yellow goatfish Goatfish Unit Mullidae Pseudupeneus maculatus Spotted goatfish Goatfish Unit Ostraciidae Acanthstracion polygonia Honeycomb cowfish Boxfishes Unit Ostraciidae Acanthstracion quadricornis Scrawled cowfish Boxfishes Unit Ostraciidae Lactophrys triqueter Smooth trunkfish Boxfishes Unit Ostraciidae Lactrophrys bicaudalis Spotted trunkfish Boxfishes Unit Ostraciidae Lactrophrys trigonus Trunkfish Boxfishes Unit Pomacanthidae Holacanthus ciliaris Queen angelfish Angelfishes Unit 4 Pomacanthidae Holacanthus tricolor Rock Beauty Angelfishes Unit Pomacanthidae Pomacanthus arcuatus Gray angelfish Angelfishes Unit Scaridae Scarus coeruleus Blue parrotfish Parrotfishes proposed Unit 2 Scaridae Scarus taeniopterus Princess parrotfish Parrotfishes proposed Unit 1 Scaridae Scarus vetula Queen parrotfish Parrotfishes proposed Unit 1 Scaridae Sparisoma aurofrenatum Redband parrotfish4 Parrotfishes proposed Unit 1 Scaridae Sparisoma chrysopterum Redtail parrotfish Parrotfishes proposed Unit 1 Scaridae Sparisoma rubripinne Yellowtail or Redfin parrotfish Parrotfishes proposed Unit 1 Scaridae Sparisoma viride Stoplight parrotfish Parrotfishes proposed Unit 1 Scombridae Scomberomorus maculatus Spanish mackerel Scombridae Scomberomorus regalis Cero Serranidae Cephalopholis fulvus Coney Grouper Unit 3 Serranidae Epinephelus adscensionis Rock Hind Grouper Unit 3 Serranidae Epinephelus cruentatus Graysby4 Grouper Unit 3 Serranidae Epinephelus guttatus Red hind Grouper Unit 3 Sphyraenidae Sphyraena barracuda Great barracuda3 1 50 CFR Part 622 - Table 2 of Appendix A to Part 622 - Caribbean Reef Fish - list of species of fish managed by the Caribbean Fishery Management Council. 2 Frequent ciguatera poisoning occurs (Olsen 1988). 3 High risk of ciguatera poisoning (Olsen 1988) though still fished and sold on St. Croix. 4 Only large individuals marketable. 5 Filefish are only occasionally sold. Customers are reticent to buy them because they consider them ugly fish. Sometimes fishers cut heads off to help sell fish. 5 Species generally considered too small to sell but are commonly recorded in port samples.
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Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table 3.4: Number of individuals 100m-2 of marketable species in each commercially harvested family recorded in Mutton Snapper Seasonal Closed Area (MSSCA) habitats. See Table 3.3 for list of marketable species recorded in roving and transect fish surveys.
Acanthuridae Balistidae
ALIN COLI DEAL GOPL SAIN SANR SARI SPAL 2.88 4.75 0.88 10.38 7.75 1.06 1.75 4.13 0 0.05 0 0.31 0.13 0.19 0.25 0
Total 33.58 0.93
Carangidae Haemulidae Holocentridae Labridae Lutjanidae Monacathidae Mullidae
6.31 0 3.25 0.06 0 0 0
0.10 1.15 2.85 0.20 0.05 0.35 1.2
12.63 0 0.63 0 0 0 0
0 1.38 2.50 0.13 0.13 0.19 0.6
0.06 0 2.75 0.06 0 0 0.38
0.19 0 1.19 0.06 0 0 0
0 0 1.00 0 0 0 0
0 0 2.13 0 0 0 0.5
19.29 2.53 16.3 0.51 0.18 0.54 2.68
Ostraciidae Pomacanthidae Scaridae Serranidae Sphyraenidae
0.063 0.13 1.44 1.25 0.06
0.1 0.55 16.05 1.00 0.15
0 0 0.38 0.38 0.13
0.25 0.50 9.31 2.88 0.06
0.06 0.13 1.44 0.63 0
0.13 0.06 0.75 0.69 0.06
0.25 0 1.75 0.5 0
0.13 0.13 5.25 0 0
0.983 1.5 36.37 7.33 0.46
Total fish 100m-2
15.44
28.55
15.03
28.62
13.39
4.38
5.50
12.27 123.18
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Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table 3.5: Estimate of total number of marketable fish by family in the Mutton Snapper Seasonal Closed Area based on the number of fish 100m-2 and size of habitat. Table 3.3 lists the marketable species recorded in roving and transect surveys. ALIN
COLI
Acanthuridae Balistidae
98,294 0
9,643 102
Carangidae Haemulidae Holocentridae Labridae Lutjanidae Monacanthidae
215,360 0 110,923 2,048 0 0
203 2,335 5,786 406 102 711
Mullidae Ostraciidae Pomacanthidae Scaridae Serranidae Sphyraenidae Total fish 100m-2
0 2,436 2,150 203 4,437 1,117 49,147 32,582 42,663 2,030 2,048 305 527,070 57,957
0 6,174 6,190 0 0 2,573 977 627 0 5,145 2,118 289 106 95,800 23,458 3,615 106 29,635 10,263 3,326 36 617 0 289 4,208 294,500 218,123 21,112
% Total fish Habitat area (ha) % Total habitat
46.24% 341.3 49.29%
0.37% 2.8 0.40%
25.84% 102.9 14.86%
19.14% 162.9 23.53%
0.93
1.74
0.81
5.08% 20.3 2.93%
Relative fish abundance 0.94 1.73 In proportion to habitat1 1 Ratio of % Total Fish to % Total habitat
DEAL
Percent of Total
SAIN
SANR
SARI
SPAL
Total
246 106,810 126,248 0 3,190 2,118
5,109 916
70 10
5,617 0
352,037 6,336
30.88% 0.56%
916 0 5,736 289 0 0
0 0 40 0 0 0
0 0 2,897 0 0 0
220,992 16,535 196,081 5,058 1,440 2,666
19.39% 1.45% 17.20% 0.44% 0.13% 0.23%
0 680 15,480 10 177 6,717 0 177 13,282 70 7,140 211,918 20 0 88,043 0 0 3,295 220 16,687 1,139,881
1.36% 0.59% 1.17%
3,536 0 176 0 0 0
GOPL
0 14,200 25,725 1,338 1,338 1,955
113
977 0 44,798 977 0 0
1.85% 0.02% 48.2 0.4 6.96% 0.06% 0.27
0.33
1.46% 13.6 1.96% 0.74
100% 692.40 100%
18.59% 7.72% 0.29% 100%
Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
DISCUSSION Of the 132 species observed only eleven common species (occurrence >1%) were ubiquitous in the eight MSSCA habitats included in this analysis (Table A3-1.1). COLI and GOPL benthic transects had highest average number of species and individuals per site. These are the two habitats with the most rugosity. The blue head wrasse (Thalassoma bifasciatum) and the bicolor damsel fish (Eupomacentrus partitus), recorded only in the transect surveys, were the most abundant fish and were ubiquitous throughout all the MSSCA habitats (Table A3-3.1). The numerical dominance of these two species is consistent with the findings of Garcia-Sais (2004), where they dominated the reef top habitat of Bajo de Sico (depth 25-30m). This was the shallowest habitat surveyed at Bajo de Sico. In this study, they were the 2nd and 3rd most abundant fish, respectively, in COLI (Coral Limestone) habitat of the MSSCA (depth 25 - 30m), the habitat most similar to the reef top at Bajo de Sico. Blue chromis (Chromis cyanea) was the most abundant species in COLI habitat and the sixth most abundant in the reef top habitat at Bajo de Sico. The blue chromis was uncommon on the wall, but the second most abundant species on the rhodolith reef at Bajo de Sico. Density of the bluehead wrasse and bicolor damselfish were much lower in COLI than the reef top at Bajo de Sico. Bluehead wrasse density was 43.8 100m-2 at COLI and 148.3 100m-2 at Bajo de Sico. Density of bicolor damselfish was 20.7 100m-2 at COLI and 400 100m-2 at the reef top at Bajo de Sico. In deeper habitats in Bajo de Sico such as the reef wall (30-40m) and the rhodolith reef (45-53m), the bluehead wrasse was less dominant, while still among the top five most abundant species, though its density fell off dramatically with depth (148.3 100m-2 at 25-30m to 7.3 100m-2 at 45-53m). The bicolor damselfish remained the first or second most abundant species in all habitats in Bajo de Sico with a density of 400 100m-2 on the reef top (2530m), 58.3 100m-2 on the reef wall (30-40m) and 160 100m-2 on the rhodolith reef (45-53m). All three species are planktivores and, along with other small species of wrasses (Labridae), gobies (Gobiidae), sea basses (Serranidae), and basslets (Grammatidae) provide an important food resource for juvenile and adult piscivorous and demersal predatory fish (Garcia-Sais, et al. 2004). Differences in abundance at these sites may relate to higher planktonic food availability at Bajo de Sico compared to COLI in the MSSCA and/or a higher number of predators at COLI. These hypotheses need to be tested. Of the eleven ubiquitous species, six were marketable species: Acanthurus chirurgus/bahianus., Cephalopholis fulvus, Holocentrus rufus, Haemulon flavolineatum, Mulloidichthys martinicus, and Scarus taeniopterus. Clepticus parrae was the most habitat specific species of with >80 individuals, occurring only in COLI, and GOPL. The percentage of ubiquity for all species is given in Tables A3-1.1 and A3-1.2. Commercially Harvested Fish Recorded in the MSSCA Commercially harvested fish recorded in the MSSCA are discussed below in relation to their trophic level, their importance to the St. Croix commercial fishery, and their habitat distribution. Clavijo et al (1980), Randall (1967) and the Froese and Pauly (2007) were used to categorize fish
114
Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
families and species by general trophic level. Below we discuss selected families, including the most common, commercially important species recorded in transects and in port samples (McCarthy and Gedamke 2009). We assumed that the number of measured fish summed across all years and gears for St. Croix (McCarthy and Gedamke 2009) reflected their importance in the St. Croix fishery. We recognize that port sampling was not randomized among gears and fishers and that there have likely been changes in the relative abundance of species in catches over time, however, these data provide information on species that are important to the fishery. Note: that while the percentage of marketable fish for each family is based only on the fish recorded in transects, the habitat distribution is based on both the roving fish census and transect techniques. Carnivorous species Eight families that are considered generalized carnivores or piscivorous species (Randall 1967) were recorded and were either commercially important, relatively common, and/or ecologically important because they are top predators. These eight families were the Carangidae (jacks), Holocentridae (squirrelfishes), Lutjanidae (snappers), Pomadasyidae (grunts), Rhincodontidae (nurse shark), Serranidae (groupers), Scombridae (mackerels), Sphyraenidae (barracuda). Four species of Carangidae were recorded comprising 6.57% of commercially marketable fish. The schooling, Decapterus punctatus (the Round Scad) made up the 83% of the carangids recorded. This is an important baitfish on St. Croix which is sometimes eaten. Bar jacks were the only carangid recorded in port samples with >300 individuals sampled (McCarthy and Gedamke 2009). This species was present in all but one habitat (SARI) in this study but comprised only <0.05% of individuals recorded in transect and roving surveys.
The Holocentridae comprised 14.77% of the marketable fish recorded in transects. Squirrelfishes made up only 1.5% of species with >300 fish port sampled (McCarthy and Gedamke 2009). The longspine squirrelfish, Holocentrus rufus, was the most common holocentrid in this study, comprising 63.8% of squirrelfish recorded. It was also the most common squirrelfish in port samples (1.3%) (McCarthy and Gedamke 2009). The Lutjanidae are considered generalized carnivores (Randall 1967) consuming fish, crabs, etc. and comprised only 1.46% of the marketable fish recorded in transects (Table 3.4). The most common snapper recorded was the mahogany snapper (Lutjanus mahogoni). Only 4 individuals (all adults) of the mutton snapper (L. analis) were recorded in two habitats in roving fish and transect surveys: ALIN and COLI (Table A3-1.2), though L. analis was observed in COLI and GOPL habitats during mutton snapper searches. No snappers were recorded in SANR, SARI or SPAL habitat. A few nurse sharks (Ginglymostoma cirratum) were caught while fishing for mutton snapper and six individuals were recorded from two habitats, COLI and DEAL. This was the only species of shark recorded during this study during any of the activities. The paucity of other shark species is consistent with the findings of (Ward-Paige et al. 2010), who found that "contemporary sharks, 115
Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
other than nurse sharks, are largely absent on reefs in the greater-Caribbean," owing, primarily, to fishing pressure. The Serranidae made up 6.34% of the commercially harvested species (Table 3.4). Four small to medium sized grouper species made up the marketable grouper. The largest of the 4 species, the rock hind, Epinephelus adscensionis, grows to 60 cm maximum total length and most commonly inhabits reefs at depths of 1 - 15 m (Clavijo et al., 1980), though it inhabits depths to 30 m (Humann, undated; Randall, 1967). It was recorded as common on St. Croix by Clavijo et al. (1980) in the 1970's and comprised 2.31% of the landings in the US Virgin Islands in the 1980's (Olsen, 1988). Only 4 individuals of this species in two habitats (COLI and SAIN) were recorded. However, depths sampled ranged from about 14m to 35m, outside the depth range where they are most commonly found. The next largest species is the red hind, E. guttatus (45 cm max total length), which is a reef dwelling species that occurs in both shallow and deep water (Clavijo et al. 1980). A total of 33 individuals were recorded in six of the eight habitats surveyed. It comprised 8.71% of the landings in the US Virgin Islands in the 1980's (Olsen, 1988) and was common on St. Croix in the 1970's (Clavijo et al. 1980). This is a very desirable commercial species. The CFMC implemented a seasonal area closure on St. Croix to protect a spawning aggregation on Lang Bank in 1993 (CFMC 1993). The coney, Cephalopholis fulvus, and graysby, E. cruentatus, both have a maximum size of 30 cm (Clavijo et al. 1980). Both were common on St. Croix in the 1970's (Clavijo et al. 1980), but only the coney is listed in the U.S. Virgin Islands' commercial landings >0.01% (Olsen, 1988) comprising 2.37% of the landings. It is reportedly more common on St. Croix than St. Thomas, comprising >6% of the landings on St. Croix vs <2% of landings on St. Thomas/St. John District between 1984 and 1989 (Beets et al. 1994). The differences in commercial landings between districts were thought to be a function of habitat and recruitment differences on the two shelves (Beets et al. 1994). When Beets et al. (1994) analyzed port sample data from 1984 - 1989, they found significant declines in mean length and the proportional representation of coneys in the total catch, providing evidence of a declining stock. A more recent analysis of port samples from St. Croix found that the coney (locally known as the "butterfish" for its yellow hue) was the most common grouper in port samples and ranked sixth in total number of measured fish on St. Croix (McCarthy and Gedamke 2009). It also comprised 43.54% of the biomass (kg. of fish caught) recorded in SEAMAP catches in 1993/4 on St. Croix and 55.37% of biomass in 2002 (Whiteman 2005). It was also the only grouper with >300 records in port samples. In this study, 80 graysby were recorded in six habitats and 749 coney in all eight habitats. The relatively high relative abundance of the Serranidae in samples was primarily a function of the ubiquitous presence and high abundance of the coney in the sampled habitats. The coney was also the most abundant grouper in transects at Bajo de Sico, Puerto Rico (Garcia-Sais 2004). Despite the high fishing pressure on coney, it clearly remains relatively abundant on St. Croix and in other parts of the Caribbean. Spear fishers on St. Croix tend to target only larger individuals of this species, which may protect spawning stock. Comparing density of coney in
116
Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
visual transects between this study and that of Chiappone et al. (2000), density of coney on hard bottom habitats in the MSSCA on St. Croix was similar to if not higher than sites surveyed by the latter. Density of coney (no. individuals 100m-2) ranged from 0.38 - 2.50 on St. Croix while density in the six sites surveyed by Chiappone et al. (2000) ranged from 0.1 in the heavily fished and highly managed Florida Keys to 1.3 in the lightly fished South Exumas, Bahamas. Chiappone et al. (2000) indicated that coneys were not targeted at intensively fished sites. This contrasts with the intense fishing pressure on this species in the Virgin Islands. Further study of its fishery status, life history including reproduction, recruitment, and spawning behavior would provide important information as to why this species was so resilient on St. Croix in the face of high fishing pressure and would help in establishing annual catch limits for this species. How important is life history in comparison with release from predation pressure and habitat? One item to note is that no spawning aggregations have been reported for coney in the literature (Beets et al. 1994, Claro and Lindeman 2003). Fishers in the US Virgin Islands have not mentioned targeting spawning aggregations of this species. Both pair spawning (Colin et al. 1987 cited in Beets et al. 1994) and haremic spawning have been reported (Beets et al. 1994) for this species. In general, grouper abundance decreased with the increasing maximum size of species; the largest of the 4 species, the rock hind, was only represented by four individuals. No large (>60 cm total length) grouper species were recorded in 135 dives in the MSSCA. Many of the larger grouper are primarily found in water deeper than surveyed in this study. However, Nassau (E. striatus) and goliath grouper (E. itajara) commonly inhabit the habitats and depths surveyed in this study (this includes roving fish censuses, transect surveys and mutton snapper searches within the MSSCA and to the west of the MSSCA) (Clavijo et al. 1980, Kojis pers. obs.). The goliath grouper was not reported in landings from the 1980's (Olsen, 1988). However, goliath grouper may have been harvested in low numbers because Olsen only reported on species that comprised at least 0.1% of total landings. In contrast to the goliath grouper, the Nassau grouper was a significant component of U.S. Virgin Islands landings in the 1980's comprising 2.25% of total landings (Olsen 1988). It was surprising that Nassau grouper were not observed in the MSSCA. Two species of Sphyraenidae were recorded: the great barracuda (Sphyraena barracuda) and the southern sennet (S. picudilla). Great barracuda were found in seven of the nine habitat surveyed (Table A3.1), missing only in SAIN and SARI, and comprised only 0.25% of the marketable fish. A total of 40 great barracuda were recorded. At each site, usually one or two medium to large barracuda, an estimated 2- 2.5 m in length, hovered in the water column near the divers. The southern sennet was recorded only in COLI. Herbivorous Fish Two families of herbivores, Acanthuridae and Scaridae, made up a total of 62.48% of the marketable fish recorded in transects (Table 3.4). These two families make up a significant portion of the catch on St. Croix. The top three species in port samples on St. Croix were two parrotfish species (redtail and stoplight parrotfish) and the blue tang (McCarthy and Gedamke 2009). Other parrotfish measured >300 times were redband, princess, redfin, queen, and unidentified parrotfishes. Parrotfishes comprised 30.5% of fish port sampled >300 times on St. 117
Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Croix and acanthurids 16.6%., comprising a total of 47% of fish port sampled >300 times (McCarthy and Gedamke 2009). Crucians have a preference for parrotfish or "bluefish". Not only do they enjoy eating parrotfish, especially red parrotfish (initial phase stoplight and redtail parrotfishes), but also they sell for less ($4/lb) than some of the other prized fish such as mutton snapper, which can sell for $6 - $8 per lb (pers. obs. - Kojis). Parrotfish are also largely caught as plate sized fish, the preferred eating size in the Virgin Islands. Mutton snapper and some other snappers are often caught at large sizes. Large fish are more expensive because of the poundage and don't meet the plate size requirement. While dolphinfish and other large pelagic fish are often cut into steaks and sold in portions, large snappers and groupers are usually sold whole making them expensive fish to buy. However, despite the cost mutton snapper is a prized food fish in the U.S. Caribbean. Of the three large Caribbean parrotfish, midnight (Scarus coelestinus), rainbow (S. guacamaia) and blue (S. coeruleus) (maximum length 3 - 4 ft (Humann, undated)), only a two juvenile blue parrotfish was recorded. Olson (1988) reported species comprising >0.01 percent of landings in the U.S. Virgin Islands. While the midnight and rainbow parrotfish were not reported in landings by Olson (1988), the blue parrotfish comprised a significant portion of total landings (1.84%); more than any other parrotfish species with exception of the stoplight parrotfish (3.99% of landings). Rainbow parrotfish may be more common in near shore in shallow water than offshore waters. Fishers report that rainbow parrotfish were once fairly common in very shallow water close to shore. Because of their size (length >1m), they were sometimes harvested by shooting them with a rifle from shore (J. LaPlace, St. Thomas, pers. com and E. Schuster, St. Croix, pers. com.). There are still reports of small schools of rainbow parrotfish grazing in shallow water on the very eastern tip of St. Croix. Juvenile rainbow parrotfish have also been observed in Secret Harbor Bay, St. Thomas, and adults in St. Thomas just off the southern reef slope at Buck Island and in shallow water in Lindberg Bay (Kojis, obs.). In conclusion, the MSSCA harbors a high diversity of fish species and a high abundance of commercially harvested coneys, surgeonfishes and parrotfishes. None of the larger grouper species and few of the large snapper and parrotfish species were observed.
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Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
LITERATURE CITED Anon. 2009. Caribbean Fisheries Data Evaluation, SEDAR Procedures Workshop 3. NOAA, NMFS, SEFSC. San Juan, PR. pp. 195. Beets, J., A. Friedlander and W. Tobias. 1994. Stock analysis of coney, Epinephelus fulvus, in St. Croix, U.S. Virgin Islands. Proc. Gulf and Caribbean Fisheries Institute. 43:403-416. Caribbean Fishery Management Council (CFMC). 1993. Amendment 2 to the Fishery Management Plan for the Shallow-water Reef Fishery of Puerto Rico and the U.S. Virgin Islands. San Juan, Puerto Rico. CFMC. San Juan, PR. 574 pp. Caribbean Fishery Management Council (CFMC). 1998. Essential Fish Habitat (EFH) Generic Amendment to the Fishery Management Plans (FMPs) of the U.S. Caribbean, Including a Draft Environmental Assessment. Vol. 1. CFMC, San Juan, PR. Caribbean Fishery Management Council (CFMC) and National Marine Fisheries Service (NMFS). 2005. Comprehensive Amendment to the Fishery Management Plans (FMPs) of the U.S. Caribbean to Address Required Provisions of the Magnuson-Stevens Fishery Conservation and Management Act. CFMC, San Juan, PR. 624 pp. http://www.caribbeanfmc.com/SCANNED%20FMPS/06%20FINAL%20SFA%20%20MAY%2003,2005/Caribbean_SFA_DSEIS/Text/SECTION%201-3.pdf. Accessed 14 Feb 2011. Chiappone, M., R.Sluka, and K. Sullivan-Sealey. 2000. Groupers (Pisces: Serranidae) in fished and protected areas of the Florida Keys, Bahamas, and northern Caribbean. Mar Ecol Prog Ser. 198:261-272. Claro, R. and K.C. Lindeman. 2003. Spawning aggregation sites of snapper and grouper species (Lutjanidae and Serranidae) on the insular shelf of Cuba. Gulf and Caribbean Research. 14(2):91-106. Clavijo, I.E., J.A. Yntema, J.C. Ogden. 1980. An annotated List of the Fishes of St. Croix, U.S. Virgin Islands. West Indies Laboratory, St. Croix, U.S. Virgin Islands. 49 pp. Colin, P.L., D.Y. Shapiro, and D. Weiler. 1987. Aspects of the reproduction of two groupers, Epinephelus guttatus and E. striatus in the West Indies. Bull. Mar. Sci. 40(2):220-230. Froese R. and D. Pauly. 2007. FishBase. www.fishbase.org.
Electronic source document available at
Garcia-Sais, J.R., R. Castro, J. Sabater-Vlavel, M. Carlo, R Esteves. 2004. Characterization of benthic Habitats and Associated Reef Communities at Bajo de Sico Seamount, Mona Passage, Puerto Rico. CFMC, San Juan, PR. 98 pp. McCarthy, K. and T. Gedamke. 2009. United States Virgin Islands Fisheries Description and Available Data: Preliminary Evaluation. NOAA, NMFS SEFSC, Sustainable Fisheries Division Contribution. SFD-2009-02. 13 pp. Olsen, D.A. 1988. The impact of ciguatera fish poisoning within a changing Caribbean environment. Population and Environment: A Journal of Interdisciplinary Studies. 10(1):1531.
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Chapter 3: Habitat Focused Fish Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Prada, M. 2003. Delineation of benthic habitats from side scan sonar mosaics from the Marine conservation District, St. Thomas, Lang Bank and Mutton Snapper Closed Area in St. Croix, U.S. Virgin Islands. Report to Caribbean Fishery Management Council, October 2003. pp 23. Randall, J.E. 1967. Food Habits of the Reef Fishers of the West Indies. Hawaii Institute of Marine Biology, University of Hawaii and Bernice P. Bishop Museum. Honolulu, HI. 94 pp. Ward-Paige, CA, C. Mora, H.K. Lotze, C. Pattengill-Semmens, L. McClenachan, E. AriasCastro, R.A. Myers. 2010. Large-scale absence of reefs in the Greater-Caribbean: A footprint of human pressures. PLoS ONE 5(8): e11968. doi:10.1371/journal.pone.0011968. Whiteman, E.A. 2005. St. Croix & St. Thomas/St. John Fisheries Independent Trap and Line Survey, 1992-2002 Summary Report: Data analysis and Conclusions. UPR Sea Grant College Program/NMFS Cooperative SEAMAP-C. UPR, Mayagüez, PR.
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APPENDICIES - CHAPTER 3
121
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Appendix 1: List of Presence / Absence of Fish Species by Habitat Table A3-1.1. Presence / Absence List of species by habitat in MSSCA in rank order of abundance. All fish recorded using roving fish census and transect techniques are combined. This table includes individuals of small species of fish originally recorded in a few roving fish censuses, but omitted from roving fish analyses in all other tables, except this table and A3.1.2. COPA habitat was omitted because the habitat described by Prada (2003) was not identified in the MSSCA. Family
Scientific name
Common Name
ALIN
COLI
DEAL
GOPL
SAIN
SANR
SARI
SPAL
Bluehead wrasse Bicolordamselfish Surgeon - Doctor or Ocean Blue chromis Black durgon
X X
X X
X X
X X
X X
X X
X X
Acanthuridae Pomacentridae Balistidae
Thalassoma bifasciatum Eupomacentrus partitus Acanthurus s chirurgus/bahianus Chromis cyanea Melichthys niger
X X X
X X X
X X X
X X X
X X X
X X X
X
Carangidae Labridae Scaridae
Decapterus punctatus Halichoeres garnoti Scarus taeniopterus
Round scad (Round robin) Yellowhead wrasse Princess parrotfish
X X X
X X
X X X
X X
X X X
X X
X X
Holocentridae Serranidae
Holocentrus rufus Cephalopholis fulvus
Longspine squirrelfish Coney
X X
X X
X X
X X
X X
X X
French grunt
X
X
X
X
X
Redband parrotfish
X
X
X
X
Blue tang Creole wrasse
X
X X
X
X X X
X X X
Labridae Pomacentridae
Pomadasyidae Scaridae Acanthuridae Labridae Mullidae Labridae Pomadasyidae
Haemulon flavolineatum Sparisoma aurofrenatum Acanthurus coeruleus Clepticus parrae Mulloidichthys martinicus Halichoeres bivittatus Haemulon plumieri
Yellow goatfish Slippery Dick White grunt
X X
122
Total
Ubiquity
X X
5563 2810
100.0% 100.0%
X X X
2273 1616 1099
100.0% 87.5% 100.0%
X X
1041 854 854
50.0% 100.0% 87.5%
X X
X X
751 749
100.0% 100.0%
X
X
X
622
100.0%
X
X
X
X
609
100.0%
X X
X
X
X
X
481 461
100.0% 25.0%
X X X
X X X
X X X
X X
X X
277 246 214
62.5% 100.0% 100.0%
X
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family
Scientific name
Opistognathidae Holocentridae Malacanthidae
Opistognathus aurifrons Myripristis jacobus Malacanthus plumieri
Yellowhead jawfish Blackbar soldierfish Sand tilefish
X
Gobidae
Coryphopterus glaucofraenum
Bridled goby
X
Chaetodontidae Balistidae Lutjanidae
Chaetodon capistratus Balistes vetula Lutjanus mahogoni
Foureye butterflyfish Queen triggerfish Mahogany snapper
X X
Scaridae Carangidae
Sparisoma rubripinne Caranx ruber
Chaetodontidae
Chaetodon striatus
Holocentridae Scaridae
Holocentrus sp. Sparisoma viride
Scaridae Mullidae Scaridae Pomacentridae Pomacanthidae Serranidae Carangidae Scaridae Labridae
Sparisoma radians Pseudupeneus maculatus Scarus iserti Chromis multilineata Holacanthus tricolor Epinephelus cruentatus Decapterus sp. Scarus vetula Bodianus rufus
Holocentridae
Holocentrus sp.
Common Name
Yellowtail or Redfin parrotfish Bar jack Banded butterflyfish Squirrelfish (adscensionis or rufus) Stoplight parrotfish Bucktooth parrotfish
ALIN
COLI
DEAL
GOPL
SAIN
SANR
SARI
X X X
X
X X
X X X
X
X X X
X X X
X
X
X
X
X X X
X X X
X X X
X X X
X X
X X
X X
X X
X X
X X
X
X
X
X
X X
X X
X
X
Spotted goatfish Striped parrotfish Brown chromis Rock beauty Graysby Scad Queen parrotfish Spanish hogfish
X
X X X X X
X
X X
unidentified
X
X
X X
X
Total
Ubiquity
X X
212 208 163
62.5% 75.0% 100.0%
X
154
75.0%
X X
150 140 116
87.5% 100.0% 50.0%
X X
X X
114 102
87.5% 87.5%
X
X
X
101
75.0%
X X
X
97 95
62.5% 50.0%
X
93
50.0%
X
X
X
X X X
91 91 89 81 80 71 67 61
100.0% 50.0% 75.0% 87.5% 75.0% 12.5% 62.5% 87.5%
59
62.5%
X
X X X X X
X X X X X
X X X X
X X X X
SPAL
X
123
X X
X X
X X
X
X
X
X X X
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family
Scientific name
Common Name
ALIN
COLI
DEAL
GOPL
SAIN
SANR
SARI
Total
Ubiquity
58
87.5%
X X
56 55
62.5% 100.0%
X X X
X X X X
53 50 42 42 40
50.0% 62.5% 75.0% 75.0% 37.5%
X
X
X
39 36
62.5% 25.0%
X X
X
X
36 33
25.0% 75.0%
X X X
X X X
X X X
31 31 30
62.5% 50.0% 62.5%
X
X
30 26
25.0% 37.5%
X
X
26 23
37.5% 62.5%
X
22 21
25.0% 75.0%
19
12.5%
Serranidae
Serranus tigrinus
Harlequin bass
X
X
X
X
X
X
X
Labridae Tetraodontidae
Halichoeres maculipinna Canthigaster rostrata
Clown wrasse Sharpnose puffer
X X
X
X
X X
X X
X X
X
Scaridae Serranidae Pomadasyidae Sphyraenidae Pomadasyidae
Sparisoma chrysopterum Serranus baldwini Haemulon carbonarium Sphyraena barracuda Haemulon sciurus
Redtail parrotfish Lantern bass Caesar grunt Great barracuda Bluestriped grunt
X X
Holocentridae Grammatidae
Holocentrus adscensionis Gramma loreto
Squirrelfish Fairy basslet
X
Lutjanidae Serranidae
Rhomboplites aurorubens Epinephelus guttatus
Vermillion snapper Red hind
Scaridae Serranidae Pomacanthidae
Sparisoma atomarium Serranus tabacarius Holacanthus ciliaris
Scaridae Carangidae
Caranx crysos
Greenblotch parrotfish Tobaccofish Queen angelfish Small unidentified parrotfish Blue runner
Monacanthidae Ostraciidae
Cantherhines pullus Lactophrys triqueter
Orangespotted filefish Smooth trunkfish
Holocentridae Ostraciidae
Neoniphon marianus Lactrophrys bicaudalis
Longjaw squirrelfish Spotted trunkfish
Gobidae
Coryphopterus personatus/hyalinus
Masked/Glass goby
X
X X X X
X X X X
X X
X X X X
X X
X
X
X X
X
X X X
X
X
SPAL
X
X X
X X
X X
X X
X
X X
X X
X
124
X
X
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family
Scientific name
Lutjanidae Labridae
Lutjanus apodus Xyrichtys splendens
Schoolmaster snapper Green razorfish
X
Pomadasyidae
Haemulon aurolineatum
Tomtate
X
Gobidae
Common Name
unidentified
Pomacentridae Rhincodontidae Chaetodontidae Pomacentridae Tetraodontidae
Microspathodon chrysurus Ptereleotris helenae Chaetodon ocellatus Chromis insolata Diodon hystrix
Yellowtail damselfish Hovering dartfish Spotfin butterfyfish Sunshinefish Porcupinefish
Ostraciidae
Lactrophrys sp.
Pomacentridae Scombridae
Stegastes planifrons Scomberomorus maculatus
Trunkfish unid. Three spot damselfish Spanish mackerel
Labridae Ostraciidae Pomadasyidae Blenniidae Serranidae Serranidae Chaetodontidae Labridae Monacanthidae
Lactrophrys trigonus Stegastes variabilis Hypoplectrus puella Paranthias furcifer Chaetodon sedentarius Halichoeres pictus Cantherhines macrocerus
Monacanthidae Sphyraenidae Chaetodontidae
Serranus tortugarum Prognathodes aculeatus
Labridae
Halichoeres radiatus
unidentified Trunkfish Cocoa damselfish Blenny Barred hamlet Creole-fish Reef butterflyfish Rainbow wrasse Whitespotted filefish Filefish unidentified Chalk bass Longsnout butterflyfish Puddingwife
ALIN
COLI
DEAL
GOPL
SAIN
X
X
SANR
SARI
X
X
SPAL
X X
X
X
X
X X
X X
X X
X
X
X X
X
X
X
X X
X
X
X
X
X
X X
X
X
X
X
X
X X X X
X
X X X
X
X X
X
X
X
125
X X X X
X
Total
Ubiquity
16 15
37.5% 25.0%
15
37.5%
14
37.5%
14 14 13 13 13
12.5% 25.0% 25.0% 12.5% 50.0%
12
50.0%
12 12
12.5% 37.5%
11 11 11 10 10 10 9 9
37.5% 25.0% 12.5% 37.5% 25.0% 12.5% 25.0% 12.5%
9
37.5%
9 9 8
50.0% 12.5% 25.0%
8
37.5%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family
Scientific name
Common Name
Pomacentridae Pomadasyidae Dactylopteridae
Eupomacentrus leucostictus Haemulon chrysargyreum Dactylopterus volitans
Beaugregory Smallmouth grunt Flying gurnard
Lutjanidae Balistidae
Ocyurus chrysurus Canthidermis sufflamen
Yellowtail snapper Ocean triggerfish
Chaenopsidae
Chaenopsis limbaughi
Yellowface / Bluethroat Pikeblenny
Dasyatidae Monacanthidae Muraenidae
Dasyatis americana Aluterus scriptus Gymnothorax moringa
Southern stingray Scrawled filefish Spotted moray
Acanthstracion polygonia Hypoplectrus unicolor Rypticus saponaceus
Honeycomb cowfish Butter hamlet Greater soapfish unknown
X X
Ostraciidae Serranidae Serranidae Muraenidae Ostraciidae
Acanthstracion quadricornis
Scrawled cowfish
Pomadasyidae Apogonidae Aulostomidae Carangidae Gobidae Gobidae Lutjanidae
Haemulon macrostomum Apogon sp. Aulostomus maculatus Caranx hippos Elacatinus genie Elactinus cf. prochilos Lutjanus analis
Spanish grunt Black spot on tail Trumpetfish Crevalle jack Cleaning goby Broadstripe goby Mutton snapper
Ostraciidae Rhincodontidae Serranidae
Ginglymostoma cirratum Epinephelus adscensionis
Boxfish unidentified Nurse shark Rock Hind
ALIN
COLI
DEAL
X X
GOPL
SAIN
SANR
SARI
SPAL
X
X
25.0% 12.5% 12.5%
7 6
25.0% 25.0%
X
6
25.0%
X
6 6 6
37.5% 25.0% 25.0%
6 6 6 5
37.5% 25.0% 25.0% 25.0%
5
12.5%
5 4 4 4 4 4 4
25.0% 25.0% 12.5% 12.5% 25.0% 25.0% 25.0%
4 4 4
25.0% 25.0% 25.0%
X
X
X X X X
X X
X X X
X X X X
X
X
X
X X
X
X X X
X X
X
X
X
X
X X X
126
X X
Ubiquity 8 8 7
X X
Total
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family
Scientific name
Common Name
Serranidae Synodontidae Pomadasyidae
Hypoplectrus chlorurus Synodus intermedius Haemulon sp.
Yellowtail hamlet Sand diver
Scorpaenidae
Scorpaena plumieri
Spotted scorpionfish
Sphyraenidae
Sphyraena borealis/picudilla
Northern/Southern sennet
Balistidae Bothidae
Xanthichthys ringens Bothus sp.
Saragassum triggerfish Flounder
Cirrhitidae Diodontidae Gobidae Holocentridae
Amblycirrhitus pinos Diodon hystrix Elacatinus evelynae (cf.) Sargocentron vexillarium Xyrichtys martinicensis Aetobatus narinari Lactrophrys triqueter Anisotremus virginicus Haemulon striatum Heteropriacanthus cruentatus Cryptotomus roseus Scarus coeruleus Equetus punctatus Pareques acuminatus Scomberomorus regalis Sphoeroides spengleri
Labridae Myliobatidae Ostraciidae Pomadasyidae Pomadasyidae Priacanthidae Scaridae Scaridae Sciaenidae Sciaenidae Scombridae Tetraodontidae
ALIN
COLI
DEAL
GOPL
SAIN
X X
SANR
SARI
SPAL
X X
Redspotted hawkfish Porcupinefish Sharknose goby Dusky squirrelfish
X X X X X X X X
Rosy razorfish Spotted eagle ray Smooth trunkfish Porkfish Striped grunt Glasseye snapper Bluelip parrotfish Blue parrotfish Spotted drum Highhat Cero Bandtail puffer
X X X X X X X X
X
X X X X Total # Individuals
127
Total
Ubiquity 4 4 3
12.5% 25.0% 12.5%
3
12.5%
3
12.5%
2 2
12.5% 12.5%
2 2 2 2
12.5% 12.5% 12.5% 12.5%
2 2 2 2 2
12.5% 12.5% 12.5% 12.5% 12.5%
2 2 2 2 2 2 2 24,223
12.5% 12.5% 12.5% 12.5% 12.5% 12.5% 12.5%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-1.2. Presence / Absence List of fish species by habitat in MSSCA, alphabetical order by family and then species. Total = total number of individuals recorded in all habitats. All fish recorded using roving fish census and transect techniques are combined. This table includes individuals of small species of fish originally recorded in a few roving fish censuses, but omitted from roving fish analyses in all tables except A3.1 and A3.2. COPA habitat was omitted because the habitat described by Prada (2003) was not identified in the MSSCA (see Chapter 2 for explanation). Family Acanthuridae Acanthuridae Apogonidae Aulostomidae Balistidae Balistidae Balistidae Balistidae Blenniidae Bothidae Carangidae Carangidae Carangidae Carangidae Carangidae
Chaenopsidae Chaetodontidae Chaetodontidae Chaetodontidae Chaetodontidae
Scientific name Acanthurus coeruleus Acanthurus chirurgus/bahianus Apogon sp. Aulostomus maculatus Balistes vetula Canthidermis sufflamen Melichthys niger Xanthichthys ringens Bothus Caranx crysos Caranx ruber Caranx cf. hippos Decapterus punctatus Decapterus sp. Chaenopsis limbaughi Chaetodon capistratus Chaetodon ocellatus Chaetodon sedentarius Chaetodon striatus
Common name
ALIN
COLI
DEAL
GOPL
SAIN
SANR
SARI
SPAL
Total
Ubiquity
X
X
X
X
X
X
X
X
481
100.0%
X
X
X
X
X X
X X
X
X
2273 4
100.0% 25.0%
Trumpetfish Queen triggerfish
X
X X
X
X
X
X
X
X
4 140
12.5% 100.0%
Ocean triggerfish Black durgon
X X
X X
X
X
X
X
X
X
6 1099
25.0% 100.0%
2 10 2 26 102 4
12.5% 37.5% 12.5% 37.5% 87.5% 12.5%
X
1041 71
50.0% 12.5%
X
6
25.0%
150
87.5%
13
25.0%
9 101
25.0% 75.0%
Blue tang Surgeon - Doctor or Ocean
Saragassum triggerfish Blenny Flounder Blue runner Bar jack Crevalle jack Round scad (Round robin) Scad Yellowface Pikeblenny/Bluethroat Pikeblenny Foureye butterflyfish
X X
X
X
X
X
X
X X
X
X X
Spotfin butterfyfish Reef butterflyfish Banded butterflyfish
X X
X
X
X
X
X
X
X
128
X X X X X
X
X
X
X
X
X
X
X
X X
X X
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Chaetodontidae Cirrhitidae Dactylopteridae Dasyatidae Dasyatidae Diodontidae Gobidae Gobidae Gobidae Gobidae Gobidae Gobidae Grammatidae Holocentridae Holocentridae Holocentridae Holocentridae Holocentridae Holocentridae Holocentridae Labridae Labridae Labridae Labridae Labridae Labridae
Scientific name Prognathodes aculeatus Amblycirrhitus pinos Dactylopterus volitans Dasyatis americana Dasyatis sabina Diodon hystrix Coryphopterus glaucofraenum Coryphopterus personatus/hyalinus Elacatinus cf. evelynae Elacatinus genie Elactinus cf prochilos sp. Gramma loreto Holocentrus Holocentrus adscensionis Holocentrus rufus Holocentrus sp. Myripristis jacobus Neoniphon marianus Sargocentron vexillarium Bodianus rufus Clepticus parrae Halichoeres bivittatus Halichoeres garnoti Halichoeres maculipinna Halichoeres pictus
Common name Longsnout butterflyfish Redspotted hawkfish Flying gurnard Southern stingray Atlantic stingray Porcupinefish Bridled goby
ALIN
Broadstripe goby unidentified Fairy basslet Squirrelfish unidentified Squirrelfish Longspine squirrelfish Squirrelfish (adscensionis or rufus) Blackbar soldierfish Longjaw squirrelfish
DEAL
GOPL
X
SAIN
SANR
SARI
SPAL
X
X
X
X X
X
X X
Masked/Glass Goby Sharknose goby Cleaning goby
COLI
X
X
X
X
X
X X X
X X X
X X X
X
X X
X X
X
X X X
Ubiquity
8 2
25.0% 12.5%
7 6 0 2
12.5% 37.5% 0.0% 12.5%
154
75.0%
19
12.5%
2 4
12.5% 25.0%
4 14 36
25.0% 37.5% 25.0%
59
62.5%
X
X
X
X X
X X
X
X X
39 751
62.5% 100.0%
X X
X
X
97 208 22
62.5% 75.0% 25.0%
X
2 61 461
12.5% 87.5% 25.0%
X X
246 854
100.0% 100.0%
X
56 9
62.5% 12.5%
X
X
X X X
X X X
X
X
Dusky squirrelfish Spanish hogfish Creole wrasse
X
X X X
X
X X
X
X
Slippery Dick Yellowhead wrasse
X X
X X
X X
X X
X X
X X
Clown wrasse Rainbow wrasse
X X
X
X
X
129
Total
X X
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Labridae Labridae Labridae Labridae Labridae Lutjanidae Lutjanidae Lutjanidae Lutjanidae Lutjanidae Lutjanidae Malacanthidae Monacanthidae Monacanthidae Monacanthidae Monacanthidae Mullidae Mullidae Muraenidae Muraenidae Myliobatidae Ophichthidae Opistognathidae Ostraciidae Ostraciidae Ostraciidae
Scientific name Halichoeres radiatus Thalassoma bifasciatum Xyrichtys martinicensis Xyrichtys splendens Lutjanus analis Lutjanus apodus Lutjanus mahogoni Lutjanus synagris Ocyurus chrysurus Rhomboplites aurorubens Malacanthus plumieri Aluterus scriptus Cantherhines macrocerus Cantherhines pullus Mulloidichthys martinicus Pseudupeneus maculatus Gymnothorax moringa Aetobatus narinari Myrichthys ocellatus Opistognathus aurifrons Acanthstracion polygonia Acanthstracion quadricornis Lactophrys triqueter
Common name
ALIN
COLI
Puddingwife
X
X
Bluehead wrasse
X
X
Rosy razorfish Green razorfish unidentified Mutton snapper Schoolmaster snapper Mahogany snapper Lane snapper Yellowtail snapper
GOPL
SAIN
SANR
SARI
SPAL
Total
Ubiquity
8
37.5%
5563
100.0%
2 15 11 4 16 116 0 7
12.5% 25.0% 37.5% 25.0% 37.5% 50.0% 0.0% 25.0%
36
25.0%
163 6
100.0% 25.0%
9 26 9
37.5% 37.5% 50.0%
277
62.5%
X
91
100.0%
X
6 5 2 0
25.0% 25.0% 12.5% 0.0%
212
62.5%
X X
X
X
X
X
X
X X X X
Vermillion snapper
X X X X
X X
Whitespotted filefish Orangespotted filefish Filefish unidentified
X X
Yellow goatfish Spotted goatfish
X
Spotted moray unidentified Spotted eagle ray Goldspotted eel
X X
X
X X
X
X
Sand tilefish Scrawled filefish
X X
X X
X
X
X X X
X X
X
X
X X X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Honeycomb cowfish
X
X X X
X
130
X
X
X
X
Yellowhead jawfish
Scrawled cowfish Smooth trunkfish
DEAL
X
X
X
X
X
6
37.5%
X
X
5 23
12.5% 62.5%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Ostraciidae Ostraciidae Ostraciidae Ostraciidae Ostraciidae Pomacanthidae Pomacanthidae Pomacentridae Pomacentridae Pomacentridae Pomacentridae Pomacentridae Pomacentridae Pomacentridae Pomacentridae Pomacentridae Pomadasyidae Pomadasyidae Pomadasyidae Pomadasyidae Pomadasyidae Pomadasyidae Pomadasyidae Pomadasyidae Pomadasyidae
Scientific name Lactrophrys bicaudalis Lactrophrys sp. Lactrophrys trigonus Lactrophrys triqueter Holacanthus ciliaris Holacanthus tricolor Chromis cyanea Chromis insolata Chromis multilineata Eupomacentrus leucostictus Eupomacentrus partitus Microspathodon chrysurus Stegastes planifrons Stegastes sp. Stegastes variabilis Anisotremus virginicus Haemulon aurolineatum Haemulon carbonarium Haemulon chrysargyreum Haemulon flavolineatum Haemulon macrostomum Haemulon plumieri Haemulon sciurus Haemulon sp.
Common name Spotted trunkfish Trunkfish unidentifed
ALIN
COLI
DEAL
GOPL
SAIN
SANR
SARI
X
X
X
X X
X
X X
X
Trunkfish
X
Smooth trunkfish Boxfish unidentified Queen angelfish Rock beauty Blue chromis Sunshinefish
X X X X
X X X
Brown chromis
X
Total
Ubiquity
X
21 12
75.0% 50.0%
X
11
25.0%
2 4 30 81 1616 13
12.5% 25.0% 62.5% 87.5% 87.5% 12.5%
89
75.0%
8
25.0%
2810
100.0% 12.5% 12.5% 0.0% 12.5%
X
Beaugregory Bicolordamselfish
SPAL
X
X X X X
X X X
X X X X
X
X
X
X
X
X
X
X X
X
X
X
X
X
X X
X
X
Yellowtail damselfish Three spot damselfish
X X
Cocoa damselfish
X
14 12 0 11
Porkfish
X
2
12.5%
Tomtate
X
15
37.5%
Caesar grunt
X
42
75.0%
Smallmouth grunt
X
8
12.5%
X X
X
X X
X
X
French grunt
X
X
X
X
X
X
X
X
622
100.0%
Spanish grunt White grunt Bluestriped grunt
X
X X X
X
X X X
X X
X
X
X X
5 214 40 3
25.0% 100.0% 37.5% 12.5%
131
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Pomadasyidae Priacanthidae Ptereleotridae Rhincodontidae Scaridae Scaridae Scaridae Scaridae Scaridae Scaridae Scaridae Scaridae Scaridae Scaridae Scaridae Scaridae Sciaenidae Sciaenidae Scombridae Scombridae Scorpaenidae Serranidae Serranidae Serranidae Serranidae
Scientific name Haemulon striatum Heteropriacanthus cruentatus Ptereleotris helenae Ginglymostoma cirratum Cryptotomus roseus Scarus coeruleus Scarus iserti Scarus taeniopterus Scarus vetula Sparisoma atomarium Sparisoma aurofrenatum Sparisoma chrysopterum Sparisoma radians Sparisoma rubripinne Sparisoma viride
Equetus punctatus Pareques acuminatus Scomberomorus maculatus Scomberomorus regalis Scorpaena plumieri Cephalopholis fulvus Epinephelus adscensionis Epinephelus cruentatus Epinephelus guttatus
Common name Striped grunt
ALIN
COLI X
Glasseye snapper Hovering dartfish Nurse shark Bluelip parrotfish Blue parrotfish Striped parrotfish Princess parrotfish Queen parrotfish
X
SAIN
SANR
SARI
SPAL
Total 2
Ubiquity 12.5%
X
2 14
12.5% 25.0%
4 2 2 91 854 67
25.0% 12.5% 12.5% 50.0% 87.5% 62.5%
31
62.5%
X
609
100.0%
X
X X
53 93
50.0% 50.0%
X
X
114 95
87.5% 50.0%
30 2
25.0% 12.5%
2
12.5%
12
37.5%
2 3
12.5% 12.5%
749
100.0%
4
25.0%
80 33
75.0% 75.0%
X
X X
X
X X X X
X
Redband parrotfish
X
X
Redtail parrotfish Bucktooth parrotfish Yellowtail or Redfin parrotfish Stoplight parrotfish
X X
X X
X
X X
Small parrotfish Spotted drum
X X
X X X
X X X
X X X
X X
X
X
X
X
X
X
X
X
X X
X
X
X X
X X
X X
X
Highhat
X
Spanish mackerel
X
Cero Spotted scorpionfish
X
X
X
X X
Rock hind Graysby Red hind
GOPL
X
Greenblotch parrotfish
Coney
DEAL
X
X
X
X X X
132
X
X
X
X
X X X
X X
X X
X
X X
X
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Serranidae Serranidae Serranidae Serranidae Serranidae Serranidae Serranidae Serranidae Serranidae Sphyraenidae Sphyraenidae Synodontidae Tetraodontidae Tetraodontidae Tetraodontidae
Scientific name Hypoplectrus chlorurus Hypoplectrus puella Hypoplectrus unicolor Paranthias furcifer Rypticus saponaceus Serranus baldwini Serranus tabacarius Serranus tigrinus Serranus tortugarum Sphyraena barracuda Sphyraena borealis/picudilla Synodus intermedius Canthigaster rostrata Diodon hystrix Sphoeroides spengleri
Common name
ALIN
COLI
Yellowtail hamlet Barred hamlet
X X
Butter hamlet Creole-fish Greater soapfish Lantern bass Tobaccofish Harlequin bass Chalk bass
X X
DEAL
GOPL
X
X
Great barracuda Northern/Southern sennet Sand diver
X
X
X
Sharpnose puffer Porcupinefish
X X
X X
X
X X X X
X X X X
SPAL
Total
Ubiquity
4 10
12.5% 25.0%
X
6 10 6 50 31 58 9
25.0% 12.5% 25.0% 62.5% 50.0% 87.5% 12.5%
X
42
75.0%
3 4
12.5% 25.0%
55 13
100.0% 50.0%
2 24,223
12.5%
X
X
X X
Bandtail puffer
SARI
X
X X X
X X
SANR
X
X X
SAIN
X X
X X
X X
X
X
X
X Total # individuals
133
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Appendix 2: Benthic Transect Fish Abundance by Habitat Table A3-2.1. Benthic Transect Fish Counts: Fish species in rank order of abundance in ALIN (Algae Invertebrates) habitat. Family
Species
Labridae Pomacentridae Labridae Carangidae Labridae Acanthuridae Holocentridae Pomacentridae Pomacentridae Serranidae Scaridae Scaridae Scaridae Scaridae Serranidae Holocentridae Holocentridae Labridae Labridae Scaridae Serranidae Gobidae Gobidae Balistidae Chaetodontidae
Thalassoma bifasciatum Eupomacentrus partitus Halichoeres garnoti Decapterus punctatus Halichoeres bivittatus Acanthurus chirurgus/bahianus Holocentrus rufus Chromis cyanea Chromis multilineata Cephalopholis fulvus Sparisoma aurofrenatum Sparisoma atomarium Sparisoma radians Serranus baldwini Holocentrus sp. Holocentrus adscensionis Halichoeres maculipinna Halichoeres pictus Scarus taeniopterus Serranus tigrinus Coryphopterus glaucofraenum Melichthys niger Chaetodon capistratus
Common name* Bluehead wrasse Bicolor damselfish Yellowhead wrasse Round scad (Round robin) Slippery dick Surgeonfish - Doctor or Ocean Longspine squirrelfish Blue chromis Brown chromis Coney Small unidentified parrotfish Redband parrotfish Greenblotch parrotfish Bucktooth parrotfish Lantern bass Squirrelfish unidentified Squirrelfish Clown wrasse Rainbow wrasse Princess parrotfish Harlequin bass Bridled goby unidentified Black durgon Foureye butterflyfish
134
Total
Grand %
Cum %
1266 549 127 100 55 46 46 46 24 20 17 16 12 10 10 7 6 6 6 5 4 3 3 2 2
52.6% 22.8% 5.3% 4.2% 2.3% 1.9% 1.9% 1.9% 1.0% 0.8% 0.7% 0.7% 0.5% 0.4% 0.4% 0.3% 0.2% 0.2% 0.2% 0.2% 0.2% 0.1% 0.1% 0.1% 0.1%
52.6% 75.4% 80.7% 84.9% 87.2% 89.1% 91.0% 92.9% 93.9% 94.7% 95.4% 96.1% 96.6% 97.0% 97.4% 97.7% 98.0% 98.2% 98.5% 98.7% 98.8% 99.0% 99.1% 99.2% 99.3%
# fish 100 m-2 79.13 34.31 7.94 6.25 3.44 2.88 2.88 2.88 1.50 1.25 1.06 1.00 0.75 0.63 0.63 0.44 0.38 0.38 0.38 0.31 0.25 0.19 0.19 0.13 0.13
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Malacanthidae Muraenidae Pomacanthidae Tetraodontidae Carangidae Chaetodontidae Cirrhitidae Gobidae Labridae Labridae Ostraciidae Scaridae Scaridae Sphyraenidae
Species Malacanthus plumieri Gymnothorax moringa Holacanthus tricolor Canthigaster rostrata Caranx ruber Chaetodon striatus Amblycirrhitus pinos Elacatinus genie Bodianus rufus
Sparisoma chrysopterum Sparisoma rubripinne Sphyraena barracuda
Common name* Sand tilefish Spotted moray Rock beauty Sharpnose puffer Bar jack Banded butterflyfish Redspotted hawkfish Cleaning goby Spanish hogfish unidentified unidentified Redtail parrotfish Yellowtail or Redfin parrotfish Great barracuda Total Total # sites surveyed Shannon Diversity Index (H') Total # species
*Common names based on Humann (undated).
135
Total
Grand %
Cum %
2 2 2 2 1 1 1 1 1 1 1 1 1 1 2406 4 2.41 39
0.1% 0.1% 0.1% 0.1% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0%
99.3% 99.4% 99.5% 99.6% 99.6% 99.7% 99.7% 99.8% 99.8% 99.8% 99.9% 99.9% 100.0% 100.0%
# fish 100 m-2 0.13 0.13 0.13 0.13 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 150.38
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.2. Roving Diver Fish Counts: Fish species in rank order of abundance in ALIN (Algae Invertebrates) habitat. Family
Species
Common name*
Carangidae Acanthuridae Holocentridae Serranidae Pomadasyidae Scaridae Acanthuridae Malacanthidae Balistidae
Decapterus punctatus Acanthurus chirurgus/bahianus Holocentrus rufus Cephalopholis fulvus Haemulon plumieri Sparisoma aurofrenatum Acanthurus coeruleus Malacanthus plumieri Balistes vetula
Holocentridae Scaridae Chaetodontidae Balistidae Chaetodontidae Holocentridae Serranidae Sphyraenidae Monacanthidae Monacanthidae Ostraciidae Balistidae Muraenidae Tetraodontidae Dasyatidae Labridae Lutjanidae
Holocentrus sp. Sparisoma chrysopterum Chaetodon capistratus Melichthys niger Chaetodon striatus Holocentrus adscensionis Epinephelus guttatus Sphyraena barracuda Aluterus scriptus Cantherhines pullus Acanthstracion quadricornis Canthidermis sufflamen
Round scad (Round robin) Surgeonfish - Doctor or Ocean Longspine squirrelfish Coney White grunt Redband parrotfish Blue tang Sand tilefish Queen triggerfish Squirrelfish (adscensionis or rufus) Redtail parrotfish Foureye butterflyfish Black durgon Banded butterflyfish Squirrelfish Red hind Great barracuda Scrawled filefish Orangespotted filefish Scrawled cowfish Ocean triggerfish unidentified Porcupinefish Southern stingray Puddingwife Mutton snapper
Diodon hystrix Dasyatis americana Halichoeres radiatus Lutjanus analis
136
320 272 145 138 135 41 36 21 20
Grand % 26.0% 22.1% 11.8% 11.2% 10.9% 3.3% 2.9% 1.7% 1.6%
Rov Cum % 26.0% 48.0% 59.8% 71.0% 81.9% 85.2% 88.2% 89.9% 91.5%
20 20 9 7 7 7 6 4 3 3 3 2 2 1 1 1 1
1.6% 1.6% 0.7% 0.6% 0.6% 0.6% 0.5% 0.3% 0.2% 0.2% 0.2% 0.2% 0.2% 0.1% 0.1% 0.1% 0.1%
93.1% 94.7% 95.5% 96.0% 96.6% 97.2% 97.6% 98.0% 98.2% 98.5% 98.7% 98.9% 99.0% 99.1% 99.2% 99.3% 99.4%
Roving Total
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Monacanthidae Mullidae Ostraciidae Ostraciidae Pomacanthidae Pomadasyidae Scaridae Sciaenidae
Species Pseudupeneus maculatus Lactophrys triqueter Lactrophrys bicaudalis Holacanthus ciliaris Haemulon flavolineatum Sparisoma rubripinne Equetus punctatus
Common name* Filefish unidentified Spotted goatfish Smooth trunkfish Spotted trunkfish Queen angelfish French grunt Yellowtail or Redfin parrotfish Spotted drum Total # individuals Total # roving fish surveys Shannon Diversity Index (H') Total # of species
*Common names based on Humann (undated).
137
Roving Total 1 1 1 1 1 1 1 1 1233 7 3.20 34
Grand % 0.1% 0.1% 0.1% 0.1% 0.1% 0.1% 0.1% 0.1%
Rov Cum % 99.4% 99.5% 99.6% 99.7% 99.8% 99.8% 99.9% 100.0%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.3. Benthic Transect Fish Counts: Fish species in rank order of abundance in COLI (Coral Limestone) habitat. Family
Scientific name
Common name*
Total
Grand %
Cum %
# fish 100 m-2
Pomacentridae Labridae Pomacentridae Labridae Scaridae Labridae Acanthuridae Scaridae Chaetodontidae Holocentridae Balistidae Grammatidae Pomacentridae Mullidae Pomadasyidae Scaridae Holocentridae
Chromis cyanea Thalassoma bifasciatum Eupomacentrus partitus Halichoeres garnoti Scarus taeniopterus Clepticus parrae Acanthurus chirurgus/bahianus Sparisoma aurofrenatum Chaetodon capistratus Myripristis jacobus Melichthys niger Gramma loreto Chromis multilineata Mulloidichthys martinicus Haemulon flavolineatum Scarus iserti Holocentrus rufus Coryphopterus personatus/hyalinus Epinephelus cruentatus Sparisoma viride Holacanthus tricolor Microspathodon chrysurus Acanthurus coeruleus Cantherhines pullus Cephalopholis fulvus Stegastes planifrons
Blue chromis Bluehead wrasse Bicolor damselfish Yellowhead wrasse Princess parrotfish Creole wrasse Surgeonfish - Doctor or Ocean Redband parrotfish Foureye butterflyfish Blackbar soldierfish Black durgon Fairy basslet Brown chromis Yellow goatfish French grunt Striped parrotfish Longspine squirrelfish
1152 876 414 226 224 100 88 62 38 38 36 23 22 22 21 20 18
32.57% 24.77% 11.70% 6.39% 6.33% 2.83% 2.49% 1.75% 1.07% 1.07% 1.02% 0.65% 0.62% 0.62% 0.59% 0.57% 0.51%
32.57% 57.34% 69.04% 75.43% 81.76% 84.59% 87.08% 88.83% 89.91% 90.98% 92.00% 92.65% 93.27% 93.89% 94.49% 95.05% 95.56%
57.60 43.80 20.70 11.30 11.20 5.00 4.40 3.10 1.90 1.90 1.80 1.15 1.10 1.10 1.05 1.00 0.90
17 13 11 8 8 7 7 7 7
0.48% 0.37% 0.31% 0.23% 0.23% 0.20% 0.20% 0.20% 0.20%
96.04% 96.41% 96.72% 96.95% 97.17% 97.37% 97.57% 97.77% 97.96%
0.85 0.65 0.55 0.40 0.40 0.35 0.35 0.35 0.35
Gobidae Serranidae Scaridae Pomacanthidae Pomacentridae Acanthuridae Monacanthidae Serranidae Pomacentridae
Masked/Glass goby Graysby Stoplight parrotfish Rock beauty Yellowtail damselfish Blue tang Orangespotted filefish Coney Three spot damselfish
138
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Pomacentridae Tetraodontidae Labridae Chaetodontidae Serranidae Holocentridae Pomacentridae Pomacanthidae Chaetodontidae Sphyraenidae Carangidae Chaetodontidae Serranidae Serranidae Mullidae Scaridae Serranidae Ostraciidae Aulostomidae Balistidae Tetraodontidae Pomadasyidae Pomadasyidae Pomadasyidae Pomadasyidae Holocentridae Holocentridae Ostraciidae Lutjanidae
Scientific name Stegastes variabilis Canthigaster rostrata Bodianus rufus Chaetodon striatus Hypoplectrus puella Neoniphon marianus Eupomacentrus leucostictus Holacanthus ciliaris Prognathodes aculeatus Sphyraena barracuda Caranx ruber Chaetodon ocellatus Hypoplectrus chlorurus Hypoplectrus unicolor Pseudupeneus maculatus Scarus vetula Serranus tigrinus Acanthstracion polygonia Aulostomus maculatus Balistes vetula Diodon hystrix Haemulon aurolineatum Haemulon carbonarium Haemulon chrysargyreum Haemulon striatum Holocentrus Holocentrus adscensionis Lactrophrys triqueter Lutjanus mahogoni
Common name*
Total
Grand %
Cum %
# fish 100 m-2
Cocoa damselfish Sharpnose puffer Spanish hogfish Banded butterflyfish Barred hamlet Longjaw squirrelfish Beaugregory Queen angelfish Longsnout butterflyfish Great barracuda Bar jack Spotfin butterfyfish Yellowtail hamlet Butter hamlet Spotted goatfish Queen parrotfish Harlequin bass Honeycomb cowfish Trumpetfish Queen triggerfish Porcupinefish Tomtate Caesar grunt Smallmouth grunt Striped grunt Squirrelfish unidentified Squirrelfish Smooth trunkfish Mahogany snapper
7 5 4 4 4 4 3 3 3 3 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 1 1
0.20% 0.14% 0.11% 0.11% 0.11% 0.11% 0.08% 0.08% 0.08% 0.08% 0.06% 0.06% 0.06% 0.06% 0.06% 0.06% 0.06% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03%
98.16% 98.30% 98.42% 98.53% 98.64% 98.76% 98.84% 98.93% 99.01% 99.10% 99.15% 99.21% 99.26% 99.32% 99.38% 99.43% 99.49% 99.52% 99.55% 99.58% 99.60% 99.63% 99.66% 99.69% 99.72% 99.75% 99.77% 99.80% 99.83%
0.35 0.25 0.20 0.20 0.20 0.20 0.15 0.15 0.15 0.15 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05
139
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Holocentridae Scaridae Scaridae Scaridae Synodontidae Labridae
Scientific name Sargocentron vexillarium Scarus coeruleus Sparisoma radians Sparisoma rubripinne Synodus intermedius
Common name*
Total
Dusky squirrelfish Blue parrotfish Bucktooth parrotfish Yellowtail or Redfin parrotfish Sand diver unidentified Total Total # sites surveyed Shannon Diversity Index (H') Total # species
1 1 1 1 1 1 3537 5 3.16 61
*Common names based on Humann (undated).
140
Cum %
# fish 100 m-2
0.03% 99.86% 0.03% 99.89% 0.03% 99.92% 0.03% 99.94% 0.03% 99.97% 0.03% 100.00%
0.05 0.05 0.05 0.05 0.05 0.05 176.85
Grand %
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.4. Roving Diver Fish Counts: Fish species in rank order of abundance in COLI (Coral Limestone) habitat. Family Balistidae Scaridae Acanthuridae Mullidae
Species Melichthys niger Scarus taeniopterus Acanthurus chirurgus/bahianus Mulloidichthys martinicus
Common Name* Black durgon Princess parrotfish Surgeonfish - Doctor or Ocean Yellow goatfish
Roving Total 246 245 172 123
Grand % 16.52% 16.45% 11.55% 8.26%
Rov Cum % 16.52% 32.98% 44.53% 52.79%
Scaridae Acanthuridae Pomadasyidae Serranidae Holocentridae Scaridae Holocentridae Scaridae Serranidae Lutjanidae Pomadasyidae Scaridae Holocentridae Pomacanthidae Carangidae Serranidae Holocentridae Scaridae Scaridae Lutjanidae Pomadasyidae Sphyraenidae Balistidae
Sparisoma aurofrenatum Acanthurus coeruleus Haemulon flavolineatum Cephalopholis fulvus Myripristis jacobus Sparisoma viride Holocentrus rufus Scarus vetula Epinephelus cruentatus Lutjanus mahogoni Haemulon sciurus Scarus iserti Holocentrus sp. Holacanthus tricolor Caranx ruber Paranthias furcifer Neoniphon marianus Sparisoma chrysopterum Sparisoma rubripinne Lutjanus apodus Haemulon carbonarium Sphyraena barracuda Balistes vetula
Redband parrotfish Blue tang French grunt Coney Blackbar soldierfish Stoplight parrotfish Longspine squirrelfish Queen parrotfish Graysby Mahogany snapper Bluestriped grunt Striped parrotfish Squirrelfish unidentified Rock beauty Bar jack Creole-fish Longjaw squirrelfish Redtail parrotfish Yellowtail or Redfin parrotfish Schoolmaster snapper Caesar grunt Great barracuda Queen triggerfish
100 75 67 54 46 33 29 27 27 26 26 21 15 12 9 9 8 8 8 7 7 7 6
6.72% 5.04% 4.50% 3.63% 3.09% 2.22% 1.95% 1.81% 1.81% 1.75% 1.75% 1.41% 1.01% 0.81% 0.60% 0.60% 0.54% 0.54% 0.54% 0.47% 0.47% 0.47% 0.40%
59.50% 64.54% 69.04% 72.67% 75.76% 77.97% 79.92% 81.73% 83.55% 85.29% 87.04% 88.45% 89.46% 90.26% 90.87% 91.47% 92.01% 92.55% 93.08% 93.55% 94.02% 94.49% 94.90%
141
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Malacanthidae Chaetodontidae Labridae Labridae Mullidae Pomadasyidae Chaetodontidae Pomacanthidae Pomadasyidae Chaetodontidae Scombridae Balistidae Carangidae Lutjanidae Lutjanidae Ostraciidae Pomadasyidae Pomadasyidae Sphyraenidae Aulostomidae Labridae Monacanthidae Monacanthidae Ostraciidae Pomadasyidae Rhincodontidae Sciaenidae Scombridae Serranidae Tetraodontidae
Species Malacanthus plumieri Chaetodon striatus Bodianus rufus Halichoeres bivittatus Pseudupeneus maculatus Haemulon chrysargyreum Chaetodon ocellatus Holacanthus ciliaris Haemulon aurolineatum Chaetodon capistratus Scomberomorus maculatus Canthidermis sufflamen Caranx crysos Lutjanus analis Rhomboplites aurorubens Lactophrys triqueter Haemulon macrostomum Haemulon plumieri Sphyraena borealis/picudilla Aulostomus maculatus Halichoeres radiatus Cantherhines macrocerus Cantherhines pullus Lactrophrys bicaudalis Anisotremus virginicus Ginglymostoma cirratum Pareques acuminatus Scomberomorus regalis Epinephelus adscensionis Diodon hystrix
Common Name* Sand tilefish Banded butterflyfish Spanish hogfish Slippery dick Spotted goatfish Smallmouth grunt Spotfin butterfyfish Queen angelfish Tomtate Foureye butterflyfish Spanish mackerel Ocean triggerfish Blue runner Mutton snapper Vermillion snapper Smooth trunkfish Spanish grunt White grunt Northern/Southern sennet Trumpetfish Puddingwife Whitespotted filefish Orangespotted filefish Spotted trunkfish Porkfish Nurse shark Highhat Cero Rock hind Porcupinefish 142
Roving Total 6 5 5 5 5 5 4 4 4 3 3 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 1
Grand % 0.40% 0.34% 0.34% 0.34% 0.34% 0.34% 0.27% 0.27% 0.27% 0.20% 0.20% 0.13% 0.13% 0.13% 0.13% 0.13% 0.13% 0.13% 0.13% 0.07% 0.07% 0.07% 0.07% 0.07% 0.07% 0.07% 0.07% 0.07% 0.07% 0.07%
Rov Cum % 95.30% 95.63% 95.97% 96.31% 96.64% 96.98% 97.25% 97.52% 97.78% 97.99% 98.19% 98.32% 98.46% 98.59% 98.72% 98.86% 98.99% 99.13% 99.26% 99.33% 99.40% 99.46% 99.53% 99.60% 99.66% 99.73% 99.80% 99.87% 99.93% 100.00%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family
Species
Common Name* Total # individuals Total # roving fish surveys Shannon Diversity Index (H') Total # species
*Common names based on Humann (undated).
143
Roving Total 1489 8 4.19 57
Grand %
Rov Cum %
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.5. Benthic Transect Fish Counts: Fish species in rank order of abundance in DEAL (Dense Algae) habitat. Family
Species
Common name*
Total
Grand %
Cum %
Pomacentridae Opistognathidae Carangidae Carangidae Labridae Gobidae Labridae Labridae Balistidae Acanthuridae Ptereleotridae Holocentridae Gobidae Serranidae Labridae Scaridae Serranidae Serranidae Chaetodontidae Malacanthidae Scaridae Tetraodontidae Blenniidae
Eupomacentrus partitus Opistognathus aurifrons Caranx ruber Decapterus punctatus Thalassoma bifasciatum Coryphopterus glaucofraenum Halichoeres bivittatus Halichoeres garnoti Melichthys niger Acanthurus chirurgus/bahianus Ptereleotris helenae Holocentrus rufus
133 73 51 50 45 26 20 14 12 7 7 5 4 4 3 3 3 3 2 2 2 2 1
27.82% 15.27% 10.67% 10.46% 9.41% 5.44% 4.18% 2.93% 2.51% 1.46% 1.46% 1.05% 0.84% 0.84% 0.63% 0.63% 0.63% 0.63% 0.42% 0.42% 0.42% 0.42% 0.21%
27.82% 43.10% 53.77% 64.23% 73.64% 79.08% 83.26% 86.19% 88.70% 90.17% 91.63% 92.68% 93.51% 94.35% 94.98% 95.61% 96.23% 96.86% 97.28% 97.70% 98.12% 98.54% 98.74%
Chaenopsidae Gobidae
Chaenopsis limbaughi Elactinus evelynae (cf.)
Bicolor damselfish Yellowhead jawfish Bar jack Round scad (Round robin) Bluehead wrasse Bridled goby Slippery dick Yellowhead wrasse Black durgon Surgeonfish - Doctor or Ocean Hovering dartfish Longspine squirrelfish unidentified Lantern Bass Green razorfish Redband parrotfish Coney Harlequin bass Foureye butterflyfish Sand tilefish Greenblotch parrotfish Sharpnose puffer Blenny Yellowface Pikeblenny/Bluethroat Pikeblenny Sharknose goby
# fish 100 m-2 16.63 9.13 6.38 6.25 5.63 3.25 2.50 1.75 1.50 0.88 0.88 0.63 0.50 0.50 0.38 0.38 0.38 0.38 0.25 0.25 0.25 0.25 0.13
1 1
0.21% 0.21%
98.95% 99.16%
0.13 0.13
Serranus baldwini Xyrichtys splendens Sparisoma aurofrenatum Cephalopholis fulvus Serranus tigrinus Chaetodon capistratus Malacanthus plumieri Sparisoma atomarium Canthigaster rostrata
144
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Gobidae Pomacentridae Serranidae Sphyraenidae
Species Elactinus prochilos (cf.) Chromis cyanea Serranus tabacarius Sphyraena barracuda
Common name*
Total
Grand %
Cum %
Broadstripe goby Blue chromis Tobaccofish Great barracuda Totals Total # sites surveyed Shannon Diversity Index (H') Total # species
1 1 1 1 478 2 3.54 29
0.21% 0.21% 0.21% 0.21%
99.37% 99.58% 99.79% 100.00%
*Common names based on Humann (undated).
145
# fish 100 m-2 0.13 0.13 0.13 0.13 59.75
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.6. Roving Diver Fish Counts: Fish species in rank order of abundance in DEAL (Dense Algae) habitat. Family Family Pomadasyidae Balistidae Acanthuridae Serranidae Lutjanidae Holocentridae Scaridae Acanthuridae Mullidae Scaridae Scaridae Malacanthidae Mullidae Holocentridae Carangidae Balistidae Serranidae Pomadasyidae Scaridae Labridae Scaridae Pomacanthidae Serranidae Monacanthidae Ostraciidae Pomadasyidae
Species Species Haemulon flavolineatum Melichthys niger Acanthurus spp. Cephalopholis fulvus Lutjanus mahogoni Holocentrus rufus Sparisoma rubripinne Acanthurus coeruleus Mulloidichthys martinicus Sparisoma aurofrenatum Scarus taeniopterus Malacanthus plumieri Pseudupeneus maculatus Myripristis jacobus Caranx ruber Balistes vetula Epinephelus cruentatus Haemulon plumieri Sparisoma viride Bodianus rufus Scarus vetula Holacanthus tricolor Epinephelus guttatus Aluterus scriptus Lactrophrys bicaudalis Haemulon carbonarium
Common name* Common name French grunt Black Durgon Surgeonfish - Doctor or Ocean Coney Mahogany snapper Longspine (Flag) squirrelfish Yellowtail or Redfin parrotfish Blue Tang Yellow goatfish Redband parrotfish Princess parrotfish Sand tilefish Spotted goatfish Blackbar soldierfish Bar jack Queen Triggerfish Graysby White grunt Stoplight parrotfish Spanish hogfish Queen parrotfish Rock Beauty Red hind Scrawled filefish Spotted trunkfish Caesar grunt 146
Roving Total
Grand %
ROV Total ROV % 217 20.43% 210 19.77% 166 15.63% 75 7.06% 68 6.40% 57 5.37% 41 3.86% 40 3.77% 35 3.30% 31 2.92% 30 2.82% 17 1.60% 16 1.51% 12 1.13% 9 0.85% 6 0.56% 6 0.56% 5 0.47% 5 0.47% 4 0.38% 3 0.28% 2 0.19% 2 0.19% 1 0.09% 1 0.09% 1 0.09%
Rov Cum % Rov Cum 20.43% 40.21% 55.84% 62.90% 69.30% 74.67% 78.53% 82.30% 85.59% 88.51% 91.34% 92.94% 94.44% 95.57% 96.42% 96.99% 97.55% 98.02% 98.49% 98.87% 99.15% 99.34% 99.53% 99.62% 99.72% 99.81%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Rhincodontidae Scaridae
Species Ginglymostoma cirratum Scarus iserti
Common name* Nurse shark Striped parrotfish Total # individuals Total # roving fish surveys Shannon Diversity Index (H') Total # species
*Common names based on Humann (undated).
147
Roving Total
Grand %
1 1 1062 3 3.54 28
0.09% 0.09%
Rov Cum % 99.91% 100.00%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.7. Benthic Transect Fish Counts: Fish species in rank order of abundance in GOPL (Gorgonian Plain) habitat. Family Labridae Pomacentridae Pomacentridae Labridae Acanthuridae Scaridae Labridae Balistidae Scaridae Serranidae Chaetodontidae Holocentridae Acanthuridae Pomadasyidae Labridae Chaetodontidae Labridae Pomacentridae Pomacentridae Serranidae Pomacanthidae Scaridae Balistidae Holocentridae Scaridae Labridae Serranidae Holocentridae
Species Thalassoma bifasciatum Eupomacentrus partitus Chromis cyanea Halichoeres garnoti Acanthurus chirurgus/bahianus Scarus taeniopterus Clepticus parrae Melichthys niger Sparisoma aurofrenatum Cephalopholis fulvus Chaetodon capistratus Holocentrus rufus Acanthurus coeruleus Haemulon flavolineatum Halichoeres maculipinna Chaetodon striatus Halichoeres bivittatus Chromis insolata Chromis multilineata Serranus tigrinus Holacanthus tricolor Balistes vetula Myripristis jacobus Sparisoma viride Epinephelus guttatus Holocentrus sp.
Common name* Bluehead wrasse Bicolor damselfish Blue chromis Yellowhead wrasse Surgeon - Doctor or Ocean Princess parrotfish Creole wrasse Black durgon Redband parrotfish Coney Foureye butterflyfish Longspine squirrelfish Blue Tang French grunt Clown wrasse Banded butterflyfish Slippery dick Sunshinefish Brown chromis Harlequin bass Rock beauty Small unidentified parrotfish Queen triggerfish Blackbar soldierfish Stoplight parrotfish unidentified Red hind Squirrelfish (adscensionis or 148
Total 1144 444 276 147 143 99 70 55 40 40 36 32 23 22 18 14 14 11 11 9 8 6 5 5 5 4 4 3
Grand % 41.97% 16.29% 10.12% 5.39% 5.25% 3.63% 2.57% 2.02% 1.47% 1.47% 1.32% 1.17% 0.84% 0.81% 0.66% 0.51% 0.51% 0.40% 0.40% 0.33% 0.29% 0.22% 0.18% 0.18% 0.18% 0.15% 0.15% 0.11%
Cum % 41.97% 58.25% 68.38% 73.77% 79.02% 82.65% 85.22% 87.23% 88.70% 90.17% 91.49% 92.66% 93.51% 94.31% 94.97% 95.49% 96.00% 96.40% 96.81% 97.14% 97.43% 97.65% 97.84% 98.02% 98.20% 98.35% 98.50% 98.61%
# fish 100 m-2 71.50 27.75 17.25 9.19 8.94 6.19 4.38 3.44 2.50 2.50 2.25 2.00 1.44 1.38 1.13 0.88 0.88 0.69 0.69 0.56 0.50 0.38 0.31 0.31 0.31 0.25 0.25 0.19
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Holocentridae Monacanthidae Ostraciidae Scaridae Gobidae Labridae Lutjanidae Opistognathidae Serranidae Tetraodontidae Balistidae Dasyatidae Gobidae Grammatidae Mullidae Muraenidae Ostraciidae Pomacentridae Scaridae Scaridae Scaridae Serranidae Serranidae Sphyraenidae
Species Neoniphon marianus Cantherhines pullus Lactophrys triqueter Scarus iserti Coryphopterus glaucofraenum Bodianus rufus Ocyurus chrysurus Opistognathus aurifrons Epinephelus cruentatus Canthigaster rostrata Xanthichthys ringens Dasyatis americana Elacatinus genie Gramma loreto Pseudupeneus maculatus Lactrophrys sp. Eupomacentrus leucostictus Sparisoma atomarium Sparisoma chrysopterum Sparisoma rubripinne Hypoplectrus unicolor Serranus tabacarius Sphyraena barracuda
Common name*
Total
rufus) Longjaw squirrelfish Orangespotted filefish Smooth trunkfish Striped parrotfish Bridled goby Spanish hogfish Yellowtail snapper Yellowhead jawfish Graysby Sharpnose puffer Saragassum triggerfish Southern stingray Cleaning goby Fairy basslet Spotted goatfish unknown Trunkfish Beaugregory Greenblotch parrotfish Redtail parrotfish Yellowtail or Redfin parrotfish Butter hamlet Tobaccofish Great barracuda Total Total # sites surveyed Shannon Diversity Index (H') Total # species
3 3 3 3 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2726 4 3.11 52
*Common names based on Humann (undated).
149
Cum %
# fish 100 m-2
0.11% 98.72% 0.11% 98.83% 0.11% 98.94% 0.11% 99.05% 0.07% 99.12% 0.07% 99.19% 0.07% 99.27% 0.07% 99.34% 0.07% 99.41% 0.07% 99.49% 0.04% 99.52% 0.04% 99.56% 0.04% 99.60% 0.04% 99.63% 0.04% 99.67% 0.04% 99.71% 0.04% 99.74% 0.04% 99.78% 0.04% 99.82% 0.04% 99.85% 0.04% 99.89% 0.04% 99.93% 0.04% 99.96% 0.04% 100.00%
0.19 0.19 0.19 0.19 0.13 0.13 0.13 0.13 0.13 0.13 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 170.38
Grand %
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.8. Roving Diver Fish Counts: Fish species in rank order of abundance in GOPL (Gorgonian Plain) habitat. Family
Species
Common name*
Acanthuridae Balistidae Serranidae Scaridae Pomadasyidae Acanthuridae Scaridae Holocentridae Holocentridae Lutjanidae Balistidae Scaridae Holocentridae Labridae Scaridae Chaetodontidae Pomacanthidae Chaetodontidae Lutjanidae Pomadasyidae Malacanthidae Mullidae Scaridae Pomadasyidae Mullidae Pomadasyidae Pomadasyidae
Acanthurus chirurgus/bahianus Melichthys niger Cephalopholis fulvus Scarus taeniopterus Haemulon flavolineatum Acanthurus coeruleus Sparisoma aurofrenatum Myripristis jacobus Holocentrus rufus Rhomboplites aurorubens Balistes vetula Scarus iserti Holocentrus sp. Bodianus rufus Sparisoma viride Chaetodon striatus Holacanthus tricolor Chaetodon capistratus Lutjanus mahogoni Haemulon plumieri Malacanthus plumieri Mulloidichthys martinicus Scarus vetula Haemulon sciurus Pseudupeneus maculatus Haemulon aurolineatum Haemulon carbonarium
Surgeonfish - Doctor or Ocean Black durgon Coney Princess parrotfish French grunt Blue Tang Redband parrotfish Blackbar soldierfish Longspine squirrelfish Vermillion snapper Queen triggerfish Striped parrotfish Squirrelfish (adscensionis or rufus) Spanish hogfish Stoplight parrotfish Banded butterflyfish Rock Beauty Foureye butterflyfish Mahogany snapper White grunt Sand tilefish Yellow goatfish Queen parrotfish Bluestriped grunt Spotted goatfish Tomtate Caesar grunt 150
Roving Total 326 258 102 98 71 66 63 60 41 32 24 24 18 10 10 9 9 8 7 7 6 6 5 4 3 3 3
Grand % 25.04% 19.82% 7.83% 7.53% 5.45% 5.07% 4.84% 4.61% 3.15% 2.46% 1.84% 1.84% 1.38% 0.77% 0.77% 0.69% 0.69% 0.61% 0.54% 0.54% 0.46% 0.46% 0.38% 0.31% 0.23% 0.23% 0.23%
Rov Cum % 25.04% 44.85% 52.69% 60.22% 65.67% 70.74% 75.58% 80.18% 83.33% 85.79% 87.63% 89.48% 90.86% 91.63% 92.40% 93.09% 93.78% 94.39% 94.93% 95.47% 95.93% 96.39% 96.77% 97.08% 97.31% 97.54% 97.77%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Scaridae Serranidae Serranidae Sphyraenidae Tetraodontidae Lutjanidae Monacanthidae Pomadasyidae Carangidae Lutjanidae Monacanthidae Ostraciidae Ostraciidae Pomacanthidae Scombridae Serranidae
Species Sparisoma rubripinne Epinephelus cruentatus Epinephelus guttatus Sphyraena barracuda Diodon hystrix Lutjanus apodus Cantherhines macrocerus Haemulon sp. Caranx ruber Ocyurus chrysurus Lactophrys triqueter Lactrophrys bicaudalis Holacanthus ciliaris Scomberomorus maculatus Rypticus saponaceus
Common name* Yellowtail or Redfin parrotfish Graysby Red hind Great barracuda Porcupinefish Schoolmaster snapper Whitespotted filefish unidentified Bar jack Yellowtail snapper Filefish unidentified Smooth trunkfish Spotted trunkfish Queen angelfish Spanish mackerel Greater soapfish Total # individuals Total # roving fish surveys Shannon diversity index Total # species
*Common names based on Humann (undated).
151
Roving Total 3 3 3 3 3 2 2 2 1 1 1 1 1 1 1 1 1302 6 3.41 43
Grand % 0.23% 0.23% 0.23% 0.23% 0.23% 0.15% 0.15% 0.15% 0.08% 0.08% 0.08% 0.08% 0.08% 0.08% 0.08% 0.08%
Rov Cum % 98.00% 98.23% 98.46% 98.69% 98.92% 99.08% 99.23% 99.39% 99.46% 99.54% 99.62% 99.69% 99.77% 99.85% 99.92% 100.00%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.9. Benthic Transect Fish Counts: Fish species in rank order of abundance in SAIN (Sand Invertebrate) habitat. Family Labridae Pomacentridae Acanthuridae Labridae Holocentridae Labridae Opistognathidae Pomacentridae Gobidae Carangidae Scaridae Serranidae Chaetodontidae Serranidae Scaridae Serranidae Tetraodontidae Acanthuridae Mullidae Labridae Serranidae Balistidae Scaridae Scorpaenidae Apogonidae Balistidae Carangidae Chaetodontidae
Species Thalassoma bifasciatum Eupomacentrus partitus Acanthurus chirurgus/bahianus Halichoeres garnoti Holocentrus rufus Halichoeres bivittatus Opistognathus aurifrons Chromis cyanea Coryphopterus glaucofraenum Caranx crysos Sparisoma aurofrenatum Serranus tigrinus Chaetodon striatus Cephalopholis fulvus Scarus taeniopterus Serranus baldwini Canthigaster rostrata Acanthurus coeruleus Mulloidichthys martinicus Halichoeres maculipinna Serranus tabacarius Balistes vetula Sparisoma atomarium Scorpaena plumieri Apogon sp. Melichthys niger Caranx ruber Prognathodes aculeatus
Common name* Bluehead wrasse Bicolor damselfish Surgeonfish - Doctor or Ocean Yellowhead wrasse Longspine squirrelfish Slippery dick Yellowhead jawfish Blue chromis Bridled goby Blue runner Redband parrotfish Harlequin bass Banded butterflyfish Coney Princess parrotfish Lantern bass Sharpnose puffer Blue tang Yellow goatfish Clown wrasse Tobaccofish Queen triggerfish Greenblotch parrotfish Spotted scorpionfish unidentified Black durgon Bar jack Longsnout butterflyfish
152
Total 1313 535 119 62 43 42 28 26 23 20 15 10 9 9 8 6 6 5 5 4 3 2 2 2 1 1 1 1
Grand % 56.72% 23.11% 5.14% 2.68% 1.86% 1.81% 1.21% 1.12% 0.99% 0.86% 0.65% 0.43% 0.39% 0.39% 0.35% 0.26% 0.26% 0.22% 0.22% 0.17% 0.13% 0.09% 0.09% 0.09% 0.04% 0.04% 0.04% 0.04%
Cum % 56.72% 79.83% 84.97% 87.65% 89.50% 91.32% 92.53% 93.65% 94.64% 95.51% 96.16% 96.59% 97.37% 96.98% 97.71% 98.23% 97.97% 98.44% 98.66% 98.83% 98.96% 99.05% 99.22% 99.14% 99.27% 99.83% 99.35% 99.87%
# fish 100 m-2 82.06 33.44 7.44 3.88 2.69 2.63 1.75 1.63 1.44 1.25 0.94 0.63 0.56 0.56 0.5 0.38 0.38 0.31 0.31 0.25 0.19 0.13 0.13 0.13 0.06 0.06 0.06 0.06
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Gobidae Holocentridae Holocentridae Labridae Malacanthidae Mullidae Ostraciidae Pomacanthidae Pomacanthidae Pomacentridae Serranidae Serranidae Serranidae Tetraodontidae
Species Elactinus prochilos (cf.) Holocentrus Holocentrus adscensionis Bodianus rufus Malacanthus plumieri Pseudupeneus maculatus Lactophrys triqueter Holacanthus ciliaris Holacanthus tricolor Chromis multilineata Epinephelus adscensionis Hypoplectrus puella Rypticus saponaceus Sphoeroides spengleri
Common name* Total Broadstripe goby 1 Squirrelfish unidentified 1 Squirrelfish 1 Spanish hogfish 1 Sand tilefish 1 Spotted goatfish 1 Smooth trunkfish 1 Queen angelfish 1 Rock Beauty 1 Brown chromis 1 Rock hind 1 Barred hamlet 1 Greater soapfish 1 Bandtail puffer 1 Total 2315 Total # sites surveyed 4 Shannon Diversity Index (H') 2.20 Total # species 42
*Common names based on Humann (undated).
153
Grand % 0.04% 0.04% 0.04% 0.04% 0.04% 0.04% 0.04% 0.04% 0.04% 0.04% 0.04% 0.04% 0.04% 0.04%
Cum % 99.44% 99.61% 99.65% 99.31% 99.78% 99.91% 99.74% 99.52% 99.57% 99.40% 99.48% 99.70% 99.96% 100.00%
# fish 100 m-2 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 144.69
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.10. Roving Diver Fish Counts: Fish species in rank order of abundance in SAIN (Sand Invertebrates) habitat. Family
Species
Acanthuridae Balistidae Pomadasyidae Serranidae Scaridae Acanthuridae Holocentridae Scaridae Balistidae Holocentridae Opistognathidae Scaridae Holocentridae Malacanthidae Scaridae Carangidae Pomadasyidae Pomadasyidae Pomacanthidae Labridae Scaridae Chaetodontidae Mullidae Chaetodontidae Pomadasyidae Ostraciidae Monacanthidae
Acanthurus chirurgus/bahianus Melichthys niger Haemulon flavolineatum Cephalopholis fulvus Scarus taeniopterus Acanthurus coeruleus Holocentrus rufus Sparisoma aurofrenatum Balistes vetula Holocentrus sp. Opistognathus aurifrons Sparisoma rubripinne Holocentrus sp. Malacanthus plumieri Scarus vetula Decapterus punctatus Haemulon carbonarium Haemulon plumieri Holacanthus ciliaris Bodianus rufus Sparisoma viride Chaetodon capistratus Pseudupeneus maculatus Chaetodon striatus Haemulon sciurus Lactophrys triqueter Cantherhines macrocerus
Common name* Surgeonfish - Doctor or Ocean Black durgon French grunt Coney Princess parrotfish Blue tang Longspine squirrelfish Redband parrotfish Queen triggerfish Squirrelfish (rufus or adscensionis) Yellowhead jawfish Yellowtail or Redfin parrotfish Squirrelfish unidentified Sand tilefish Queen parrotfish Round scad (Round robin) Caesar grunt White grunt Queen angelfish Spanish hogfish Stoplight parrotfish Foureye butterflyfish Spotted goatfish Banded butterflyfish Bluestriped grunt Smooth trunkfish Whitespotted filefish 154
Roving Total 321 135 100 89 50 48 40 28 21 21 21 21 16 16 15 14 12 9 7 6 5 4 4 3 3 3 2
Grand % 31.23% 13.13% 9.73% 8.66% 4.86% 4.67% 3.89% 2.72% 2.04% 2.04% 2.04% 2.04% 1.56% 1.56% 1.46% 1.36% 1.17% 0.88% 0.68% 0.58% 0.49% 0.39% 0.39% 0.29% 0.29% 0.29% 0.19%
Rov Cum % 31.23% 44.36% 54.09% 62.74% 67.61% 72.28% 76.17% 78.89% 80.93% 82.98% 85.02% 87.06% 88.62% 90.18% 91.63% 93.00% 94.16% 95.04% 95.72% 96.30% 96.79% 97.18% 97.57% 97.86% 98.15% 98.44% 98.64%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Serranidae Pomacanthidae Mullidae Ostraciidae Tetraodontidae Serranidae Ostraciidae Lutjanidae Lutjanidae Lutjanidae Serranidae
Species Epinephelus guttatus Holacanthus tricolor Mulloidichthys martinicus Acanthstracion polygonia Diodon hystrix Epinephelus cruentatus Lactrophrys sp. Lutjanus apodus Lutjanus mahogoni Ocyurus chrysurus Rypticus saponaceus
Common name* Red hind Rock beauty Yellow goatfish Honeycomb cowfish Porcupinefish Graysby Trunkfish Schoolmaster snapper Mahogany snapper Yellowtail snapper Greater soapfish Total # Individuals Total # surveys Shannon Diversity Index (H') Total # species
*Common names based on Humann (undated).
155
Roving Total 2 2 2 1 1 1 1 1 1 1 1 1028 5 3.85 44
Grand % 0.19% 0.19% 0.19% 0.10% 0.10% 0.10% 0.10% 0.10% 0.10% 0.10% 0.10%
Rov Cum % 98.83% 99.03% 99.22% 99.32% 99.42% 99.51% 99.61% 99.71% 99.81% 99.90% 100.00%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.11. Benthic Transect Fish Counts: Fish species in rank order of abundance in SANR (Sand No Ripple) habitat. Family Labridae Pomacentridae
Species Thalassoma bifasciatum Eupomacentrus partitus
Common name* Bluehead wrasse Bicolor damselfish
Labridae Gobidae Opistognathidae Labridae Acanthuridae Holocentridae Serranidae Scaridae Serranidae Scaridae Serranidae Chaetodontidae Serranidae Scaridae Tetraodontidae Balistidae Carangidae
Halichoeres garnoti Coryphopterus glaucofraenum Opistognathus aurifrons Halichoeres bivittatus Acanthurus chirurgus/bahianus Holocentrus rufus Serranus tabacarius Sparisoma aurofrenatum Cephalopholis fulvus Sparisoma radians Serranus tortugarum Chaetodon striatus Serranus tigrinus Sparisoma atomarium Canthigaster rostrata Balistes vetula Caranx sp.
Chaenopsidae Malacanthidae Chaetodontidae Chaetodontidae Chaetodontidae Holocentridae
Chaenopsis limbaughi Malacanthus plumieri Chaetodon capistratus Chaetodon ocellatus Chaetodon sedentarius Holocentrus adscensionis
Yellowhead wrasse Bridled goby Yellowhead jawfish Slippery Dick Surgeonfish - Doctor or Ocean Longspine squirrelfish Tobaccofish Redband parrotfish Coney Bucktooth parrotfish Chalk Bass Banded butterflyfish Harlequin bass Greenblotch parrotfish Sharpnose puffer Queen triggerfish unidentified Yellowface pikeblenny/Bluethroat pikeblenny Sand tilefish Foureye butterflyfish Spotfin butterfyfish Reef butterflyfish Squirrelfish
156
Total Grand % 247 30.53% 203 25.09%
Cum % 30.53% 55.62%
# fish 100 m-2 15.44 12.69
79 62 43 37 17 17 12 11 11 6 6 5 5 4 4 3 3
9.77% 7.66% 5.32% 4.57% 2.10% 2.10% 1.48% 1.36% 1.36% 0.74% 0.74% 0.62% 0.62% 0.49% 0.49% 0.37% 0.37%
65.39% 73.05% 78.37% 82.94% 85.04% 87.14% 88.63% 89.99% 91.35% 92.09% 92.83% 93.45% 94.07% 94.56% 95.06% 95.43% 95.80%
4.94 3.88 2.69 2.31 1.06 1.06 0.75 0.69 0.69 0.38 0.38 0.31 0.31 0.25 0.25 0.19 0.19
3 3 2 2 2 2
0.37% 0.37% 0.25% 0.25% 0.25% 0.25%
96.17% 96.54% 96.79% 97.03% 97.28% 97.53%
0.19 0.19 0.13 0.13 0.13 0.13
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Labridae Ptereleotridae Serranidae Apogonidae Balistidae Blenniidae Dactylopteridae Labridae Labridae Ostraciidae Ostraciidae Pomacanthidae Pomacentridae Pomacentridae Scaridae Sphyraenidae Synodontidae
Species Halichoeres maculipinna Ptereleotris helenae Serranus baldwini Apogon sp. Melichthys niger Dactylopterus volitans Bodianus rufus Xyrichtys martinicensis Lactophrys triqueter Lactrophrys sp. Holacanthus tricolor Chromis cyanea Chromis multilineata Scarus taeniopterus Sphyraena barracuda Synodus intermedius
Common name* Clown wrasse Hovering dartfish Lantern bass unidentified Black durgon Blenny Flying gurnard Spanish hogfish Rosy razorfish Smooth trunkfish Trunkfish Rock beauty Blue chromis Brown chromis Princess parrotfish Great barracuda Sand diver Total Total # sites surveyed Shannon Diversity Index (H') Total # species
*Common names based on Humann (undated).
157
Total Grand % Cum % 2 0.25% 97.78% 2 0.25% 98.02% 2 0.25% 98.27% 1 0.12% 98.39% 1 0.12% 98.52% 1 0.12% 98.64% 1 0.12% 98.76% 1 0.12% 98.89% 1 0.12% 99.01% 1 0.12% 99.13% 1 0.12% 99.26% 1 0.12% 99.38% 1 0.12% 99.51% 1 0.12% 99.63% 1 0.12% 99.75% 1 0.12% 99.88% 1 0.12% 100.00% 809 4 3.26 42
# fish 100 m-2 0.13 0.13 0.13 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 50.56
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.12. Roving Diver Fish Counts: Fish species in rank order of abundance in SANR (Sand No Ripple) habitat. Family
Species
Acanthuridae Serranidae Carangidae Acanthuridae Mullidae Holocentridae Malacanthidae Pomadasyidae Scaridae Balistidae Scaridae Scaridae Mullidae Holocentridae Pomadasyidae Balistidae Carangidae Chaetodontidae Holocentridae Ostraciidae Chaetodontidae Ostraciidae Dactylopteridae Holocentridae Holocentridae Labridae Scombridae
Acanthurus chirurgus/bahianus Cephalopholis fulvus Decapterus sp. Acanthurus coeruleus Mulloidichthys martinicus Holocentrus rufus Malacanthus plumieri Haemulon plumieri Sparisoma rubripinne Melichthys niger Sparisoma aurofrenatum Scarus taeniopterus Pseudupeneus maculatus Holocentrus sp. Haemulon flavolineatum Balistes vetula Caranx ruber Chaetodon striatus Holocentrus sp. Lactrophrys trigonus Chaetodon capistratus Lactrophrys bicaudalis Dactylopterus volitans Holocentrus adscensionis Myripristis jacobus Halichoeres radiatus Scomberomorus maculatus
Common name* Surgeonfish - Doctor or Ocean Coney Scad Blue tang Yellow goatfish Longspine squirrelfish Sand tilefish White grunt Yellowtail or Redfin parrotfish Black durgon Redband parrotfish Princess parrotfish Spotted goatfish Squirrelfish (adscensionis or rufus) French grunt Queen triggerfish Bar jack Banded butterflyfish Squirrelfish unidentified Trunkfish Foureye butterflyfish Spotted trunkfish Flying gurnard Squirrelfish Blackbar soldierfish Puddingwife Spanish mackerel 158
Roving Total 249 78 70 63 59 43 43 29 21 20 19 17 13 12 12 9 8 8 7 5 4 4 3 2 2 2 2
Grand % 30.37% 9.51% 8.54% 7.68% 7.20% 5.24% 5.24% 3.54% 2.56% 2.44% 2.32% 2.07% 1.59% 1.46% 1.46% 1.10% 0.98% 0.98% 0.85% 0.61% 0.49% 0.49% 0.37% 0.24% 0.24% 0.24% 0.24%
Rov Cum % 30.37% 39.88% 48.41% 56.10% 63.29% 68.54% 73.78% 77.32% 79.88% 82.32% 84.63% 86.71% 88.29% 89.76% 91.22% 92.32% 93.29% 94.27% 95.12% 95.73% 96.22% 96.71% 97.07% 97.32% 97.56% 97.80% 98.05%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Bothidae Carangidae Dasyatidae Monacanthidae Myliobatidae Ostraciidae Ostraciidae Ostraciidae Ostraciidae Pomacanthidae Pomacanthidae Pomadasyidae Pomadasyidae Scaridae Scaridae Serranidae
Species Bothus Caranx crysos Dasyatis americana Aetobatus narinari Acanthstracion polygonia Lactophrys triqueter Lactrophrys sp. Holacanthus ciliaris Holacanthus tricolor Haemulon aurolineatum Haemulon carbonarium Scarus coeruleus Scarus iserti Epinephelus guttatus
Common name* Flounder Blue runner Southern stingray filefish unidentified Spotted eagle ray Honeycomb cowfish Smooth trunkfish Trunkfish boxfish unidentified Queen angelfish Rock beauty Tomtate Caesar grunt Blue parrotfish Striped parrotfish Red hind Total # individuals Total # roving fish surveys Shannon Diversity Index (H') Total # species
*Common names based on Humann (undated).
159
Roving Total 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 820 8 3.79 43
Grand % 0.12% 0.12% 0.12% 0.12% 0.12% 0.12% 0.12% 0.12% 0.12% 0.12% 0.12% 0.12% 0.12% 0.12% 0.12% 0.12%
Rov Cum % 98.17% 98.29% 98.41% 98.54% 98.66% 98.78% 98.90% 99.02% 99.15% 99.27% 99.39% 99.51% 99.63% 99.76% 99.88% 100.00%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.13. Benthic Transect Fish Counts: Fish species in rank order of abundance in SARI (Sand Ripple) habitat. Family Labridae Pomacentridae Opistognathidae Labridae
Species Thalassoma bifasciatum Eupomacentrus partitus Opistognathus aurifrons Halichoeres garnoti
Acanthuridae Scaridae Holocentridae Labridae Serranidae Acanthuridae Balistidae Malacanthidae Ostraciidae Scaridae Serranidae Tetraodontidae
Acanthurus chirurgus/bahianus Scarus taeniopterus Holocentrus rufus Halichoeres bivittatus Cephalopholis fulvus Acanthurus coeruleus Balistes vetula Malacanthus plumieri Lactrophrys sp. Sparisoma aurofrenatum Serranus tigrinus Canthigaster rostrata
Common name* Bluehead wrasse Bicolor damselfish Yellowhead jawfish Yellowhead wrasse Surgeonfish - Doctor or Ocean Princess parrotfish Longspine squirrelfish Slippery dick Coney Blue tang Queen triggerfish Sand tilefish Trunkfish Redband parrotfish Harlequin bass Sharpnose puffer Total Total # of sites surveyed Shannon Diversity Index Total # species
*Common names based on Humann (undated).
160
Total 90 24 18 8
Grand % 53.57% 14.29% 10.71% 4.76%
Cum % 53.57% 67.86% 78.57% 83.33%
# fish 100 m-2 22.50 6.00 4.50 2.00
6 6 4 3 2 1 1 1 1 1 1 1 168 1 2.40 16
3.57% 3.57% 2.38% 1.79% 1.19% 0.60% 0.60% 0.60% 0.60% 0.60% 0.60% 0.60%
86.90% 90.48% 92.86% 94.64% 95.83% 96.43% 97.02% 98.81% 98.21% 100.00% 99.40% 97.62%
1.50 1.50 1.00 0.75 0.50 0.25 0.25 0.25 0.25 0.25 0.25 0.25 42.00
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3.14. Roving Diver Fish Counts: Fish species in rank order of abundance in SARI (Sand Ripple) habitat. Family
Species
Common name*
Acanthuridae Balistidae Holocentridae Serranidae Scaridae Pomadasyidae Acanthuridae Holocentridae Mullidae Scaridae Malacanthidae Monacanthidae Balistidae Ostraciidae Pomadasyidae Serranidae Serranidae
Acanthurus chirurgus/bahianus Melichthys niger Holocentrus sp. Cephalopholis fulvus Sparisoma aurofrenatum Haemulon flavolineatum Acanthurus coeruleus Myripristis jacobus Pseudupeneus maculatus Scarus taeniopterus Malacanthus plumieri
Surgeonfish - Doctor or Ocean Black durgon Squirrelfish unidentified Coney Redband parrotfish French grunt Blue tang Blackbar soldierfish Spotted goatfish Princess parrotfish Sand tilefish file fish unidentified Queen triggerfish Trunkfish White grunt Graysby Red hind Total # individuals Total # roving fish surveys Shannon Diversity Index (H') Total # species
Balistes vetula Lactrophrys sp. Haemulon plumieri Epinephelus cruentatus Epinephelus guttatus
*Common names based on Humann (undated).
161
Roving Total 55 51 19 17 15 12 9 5 4 4 2 2 1 1 1 1 1 200 1 3.05 17
Grand % 27.50% 25.50% 9.50% 8.50% 7.50% 6.00% 4.50% 2.50% 2.00% 2.00% 1.00% 1.00% 0.50% 0.50% 0.50% 0.50% 0.50%
Rov Cum % 27.50% 53.00% 62.50% 71.00% 78.50% 84.50% 89.00% 91.50% 93.50% 95.50% 96.50% 97.50% 98.00% 100.00% 99.50% 98.50% 99.00%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.15. Benthic Transect Fish Counts: Fish species in rank order of abundance in SPAL (Sparse Algae) habitat. Family Labridae Pomacentridae Labridae Scaridae Pomacentridae Acanthuridae Scaridae Labridae Holocentridae Pomacentridae Scaridae Serranidae Labridae Labridae Tetraodontidae Chaetodontidae Mullidae Blenniidae Chaetodontidae Gobidae Gobidae Holocentridae Acanthuridae Chaetodontidae Muraenidae Ostraciidae Pomacanthidae Pomadasyidae
Species Thalassoma bifasciatum Eupomacentrus partitus Halichoeres garnoti Sparisoma radians Chromis cyanea Acanthurus chirurgus/bahianus Sparisoma aurofrenatum Halichoeres bivittatus Holocentrus rufus Chromis multilineata Sparisoma chrysopterum Serranus baldwini Halichoeres maculipinna Xyrichtys splendens Canthigaster rostrata Chaetodon sedentarius Pseudupeneus maculatus Chaetodon striatus Coryphopterus glaucofraenum Holocentrus adscensionis Acanthurus coeruleus Chaetodon capistratus Gymnothorax moringa Lactrophrys bicaudalis Holacanthus tricolor Haemulon macrostomum
Common name* Bluehead wrasse Bicolor damselfish Yellowhead wrasse Bucktooth parrotfish Blue chromis Surgeon - Doctor or Ocean Redband parrotfish Slippery dick Longspine squirrelfish Brown chromis Redtail parrotfish Lantern bass Clown wrasse Green razorfish Sharpnose puffer Reef butterflyfish Spotted goatfish Blenny Banded butterflyfish Bridled goby unidentified Squirrelfish Blue Tang Foureye butterflyfish Spotted moray Spotted trunkfish Rock beauty Spanish grunt
162
Total 329 278 88 63 37 32 32 25 14 10 10 9 8 7 6 4 4 3 3 3 3 3 1 1 1 1 1 1
Grand % 33.64% 28.43% 9.00% 6.44% 3.78% 3.27% 3.27% 2.56% 1.43% 1.02% 1.02% 0.92% 0.82% 0.72% 0.61% 0.41% 0.41% 0.31% 0.31% 0.31% 0.31% 0.31% 0.10% 0.10% 0.10% 0.10% 0.10% 0.10%
Cum % 33.64% 62.07% 71.06% 77.51% 81.29% 84.56% 87.83% 90.39% 91.82% 92.84% 93.87% 94.79% 95.60% 96.32% 96.93% 97.34% 97.75% 99.28% 98.06% 98.36% 98.98% 98.67% 99.39% 99.49% 99.69% 100.00% 99.90% 99.80%
# fish 100 m-2 41.13 34.75 11.00 7.88 4.63 4.00 4.00 3.13 1.75 1.25 1.25 1.13 1.00 0.88 0.75 0.50 0.50 0.38 0.38 0.38 0.38 0.38 0.13 0.13 0.13 0.13 0.13 0.13
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Scaridae
Species Cryptotomus roseus
Common name* Bluelip parrotfish Total Total # sites surveyed Shannon Diversity Index Total # species
*Common names based on Humann (undated).
163
Total 1 978 2 2.95 29
Grand % 0.10%
Cum % 99.59%
# fish 100 m-2 0.13 122.25
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Table A3-2.16. Roving Diver Fish Counts: Fish species in rank order of abundance in SPAL (Sparse Algae) habitat. Family Carangidae Acanthuridae Holocentridae Acanthuridae Pomadasyidae Scaridae Serranidae Mullidae Holocentridae Pomadasyidae Balistidae Pomadasyidae Malacanthidae Sphyraenidae Balistidae Ostraciidae Ostraciidae Scaridae Chaetodontidae Holocentridae Labridae Scaridae Scaridae Carangidae Pomacanthidae Priacanthidae
Species Decapterus punctatus Acanthurus chirurgus/bahianus Holocentrus rufus Acanthurus coeruleus Haemulon flavolineatum Sparisoma aurofrenatum Cephalopholis fulvus Pseudupeneus maculatus Myripristis jacobus Haemulon plumieri Melichthys niger Haemulon carbonarium Malacanthus plumieri Sphyraena barracuda Balistes vetula Lactrophrys bicaudalis Lactrophrys trigonus Sparisoma chrysopterum Chaetodon striatus Holocentrus adscensionis Bodianus rufus Scarus vetula Sparisoma rubripinne Caranx ruber Holacanthus tricolor Heteropriacanthus cruentatus
Common name* Round scad (Round robin) Surgeon - Doctor or Ocean Longspine squirrelfish Blue tang French grunt Redband parrotfish Coney Spotted goatfish Blackbar soldierfish White grunt Black durgon Caesar grunt Sand tilefish Great barracuda Queen triggerfish Spotted trunkfish Trunkfish Redtail parrotfish Banded butterflyfish Squirrelfish Spanish hogfish Queen parrotfish Yellowtail or Redfin parrotfish Bar jack Rock beauty Glasseye snapper
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Roving Total 550 131 108 48 47 33 20 9 8 8 6 6 5 5 4 3 3 3 2 2 2 2 2 1 1 1
Grand % 54.40% 12.96% 10.68% 4.75% 4.65% 3.26% 1.98% 0.89% 0.79% 0.79% 0.59% 0.59% 0.49% 0.49% 0.40% 0.30% 0.30% 0.30% 0.20% 0.20% 0.20% 0.20% 0.20% 0.10% 0.10% 0.10%
Rov Cum % 54.40% 67.36% 78.04% 82.79% 87.44% 90.70% 92.68% 93.57% 95.15% 94.36% 96.34% 95.75% 96.83% 97.33% 97.73% 98.02% 98.32% 98.62% 99.01% 99.21% 98.81% 99.41% 99.60% 99.70% 100.00% 99.90%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Family Serranidae
Species Epinephelus cruentatus
Common name* Graysby Total # individuals Total # roving fish surveys Shannon Diversity Index (H') Total # species
*Common names based on Humann (undated).
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Roving Total 1 1011 4 2.46 27
Grand % 0.10%
Rov Cum % 99.80%
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Appendix 3 - Queen conch (Strombus gigas) Distribution and Abundance in MSSCA Habitats Introduction Queen conch distribution and abundance were not the focus of this study. However, this is an important fishery species on St. Croix and the focus of one if the Caribbean Fisheries Management Council's fishery management plans (CFMC 1996). Thus, it was considered important to collect data on this species in the MSSCA while carrying out benthic transects and roving fish censuses. Materials and Methods Queen conch (Strombus gigas) were recorded in transects conducted during benthic fish transect data collection and during roving fish censuses. Transect data was collected primarily in June August 2009 with some collected in May and June 2010. Therefore, surveys were done during the beginning and middle of the spawning season for queen conch and during the June 1st October 30th closed season for queen conch and March 1st to June 30th closure of the MSSCA. Conch were classified as adult if they had a flared or thick lip. Results Transects A total of 74 adult and juvenile live queen conch were observed in the benthic transect census. The highest density was in Dense Algae (DEAL) with 200 conch ha-2 followed by Algae with Invertebrates (ALIN) with 170 conch ha-2 (Table A3 - 3.1). Based on the density of queen conch and the total area of each habitat in the MSSCA, we estimated that ALIN has 59,728 queen conch and a total of about 69,786 queen conch are found in the MSSCA. The 4.7ha of COPA habitat were not included in the calculations because COPA habitat could not be identified and appeared to be a combination of COLI (Coral Limestone) and SAIN (Sand Invertebrates) habitat. (see Chapter 2). Roving Fish Surveys Queen conch were also counted during roving fish surveys. Table A3-3.2 provides further information on the habitats were queen conch were found in greatest abundance. Almost half the conch recorded in the roving surveys were found in Sand with No Ripples (SANR). ALIN and DEAL were the two other habitats where the majority of live conch were recorded. In contrast to the transect data, roving surveys indicate that conch density is higher in SANR than ALIN and conch are common in DEAL. Though few queen conch were recorded in COLI habitat, they were observed to be fairly common at one site in the narrow sandy grooves that characterize this habitat. Also, there were a large number of live conch in the crook of the reef at Nicky's reef in 45.7m (150ft) depth (Fig.
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1.10). Conch were likely migrating and piled up in the crook of this L-shaped reef. Conch tracks covered the bottom. Table A3-3.1: Transects: Estimated adult and juvenile queen conch (Strombus gigas) in each habitat. Estimated number of adult and juvenile queen conch per hectare is based on identification of adults and juveniles during surveys and proportional distribution of conch identified only as live based on proportion of adults and juveniles recorded in the habitat. Zeros represent no observations of conch in transects in that habitat. ALIN Total # conch Area surveyed (ha) Estimated # of juv/adult conch Est. # of adult conch per ha Est. # of juvenile conch per ha Est. # of conch in habitat
COLI DEAL GOPL
SAIN
SANR
SARI
SPAL
Total
28
1
16
2
0
27
0
0
74
0.16
0.2
0.08
0.16
0.176
0.16
0.04
0.08
1.06
100
185.71
0
0
158.5
0
0
75
14.29
12.5
0
11.25
0
0
560
1,286
0
8,134
0
0 69,786
51
59,728
78
% of conch in 85.59% 0.11% 0.80% 1.84% 0.00% 11.66% 0.00% 0.00% each habitat 1 Queen conch were not identified as adult or juvenile in this habitat.
100%
Table A3-3. 2: Number of queen conch (Strombus gigas) recorded during roving fish surveys.
No. of conch No. of roving fish surveys Mean no. of conch per survey Percentage of conch observed in each habitat
ALIN
COLI
DEAL
GOPL
SPAL
96
1
59
0
1
5
7
8
3
6
4
13.7
0.1
19.7
0.0
29.72
0.31
18.27
0.00
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SAIN SANR
SARI
Total
159
2
323
5
8
1
42
0.3
1.0
19.9
2.0
7.7
0.31
1.55
49.23
0.62
100.00
Chapter 3: Habitat Focused Surveys in the Mutton Snapper (Lutjanus analis) Seasonal Closed Area
Discussion The Magnuson-Stevens Fisheries Conservation Act defines Essential Fish Habitat (EFH) as those habitats necessary for the species of concern to grow to maturity, spawn, breed, or feed. Stoner and Ray-Clup (2000) studied the critical density for queen conch to successfully reproduce. They concluded that the density at which mating and spawning never occurred was <56 conch ha-1 and <48 conch ha-1, respectively (Stoner and Ray-Clup, 2000). Reproductive activity reached an asymptote at 200 conch ha-1. Adult queen conch density in 3 of the 8 habitats surveyed ranged from 100 - 186 ha-1, well above the minimum density for mating and spawning, but less than the density for maximum reproductive activity. These habitats comprised 392.3 ha or 57% of the total area of the MSSCA. Tobias (2005) reported that 98% of queen conch in back reef embayments on St. Croix were recorded in sand, algal plain and seagrass habitats, or a combination of these habitats. These habitats comprised 96.3% of the habitat surveyed. The majority of the conch recorded were juveniles (87%). In contrast, 80% of the conch recorded in this study were adults in ALIN, DEAL and SANR transects. Only SANR was truly a sand habitat. The other two habitats were hard bottom habitats with a thin overlay of sand with algae. There were scattered small, depressions with pockets of deeper sand. Conch have the ability to move up to 9 km in six months and the natural migration of conch is from inshore waters to spawn in the summer months to deeper offshore waters in the winter months (Appeldorn 1997). Thus, the conch at 45 m at Nicky's reef in June 2010 may have been blocked from migrating into shallower water. Conch found in deepwater on St. Croix may, in some instances, be blocked from migrating into shallower waters by slope edge reefs. It is unknown if conch can obtain enough energy to reproduce at 45m depth. If they can, reefs that block conch migrations, may increase mating activities by increasing local density. Literature Cited Appeldorn, R.S. 1997. Status of the queen conch fishery in the Caribbean Sea. pp. 40-49. In: J.M. Posada and G. Garcia-Moliner (eds.). Proc. of the International Queen Conch Conference, San Juan, PR, July 29-31, 1996. CFMC, San Juan, PR. 155 pp. Caribbean Fisheries Management Council. 1996. Fishery management plan, regulatory impact review, and final environmental impact statement for the queen conch resources of Puerto Rico and the United States Virgin Islands. San Juan, PR. 41 pp. Stoner, A.W. and M. Ray-Clup. 2000. Evidence for Allee effects in an over-harvested marine gastropod: density-dependent mating and egg production. Mar. Ecol. Prog. Ser. 202:297-302. Tobias, W. 2005. Assessment of Conch Densities in Backreef Embayments on the northeast and southeast coast of St. Croix, U.S. Virgin Islands. Report to the SEAMAP-C. 34 pp.
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Appendix 4 - Abstract 63rd Gulf and Caribbean Fisheries Institute Meeting Distribution and Abundance of Fish Populations in Various Habitats in the Mutton Snapper (Lutjanus analis) Conservation Area on the South Shelf St. Croix, U.S. Virgin Islands Distribution et abondance des populations de poisons dans les divers habitats de la Snapper Mouton (Lutjanus analis) Zone de conservation de la Croix du Sud du plateau Saint-Laurent, les îles Vierges américaines Distribución y abundancia de las poblaciones de peces en diferentes hábitats en el pargo criollo (Lutjanus analis) Área de Conservación en el Sur Plataforma St. Croix, Islas Vírgenes de EE.UU
BARBARA LOUISE KOJIS and NORMAN JOHN QUINN St. Thomas, U.S. Virgin Islands ABSTRACT In 1993, the Caribbean Fishery Management Council and US Virgin Islands Government established the Mutton Snapper Seasonal Closed Area (MSSCA) south of St. Croix from March 1 – June 30th to protect a spawning aggregation of mutton snapper (Lutjanus analis). Bottom tended fishing gear was subsequently banned year round in the closed area to protect coral reef habitat. The habitat within the closed area was mapped. Using benthic transects and roving diver survey techniques a total of 143 fish species and 19,843 individuals were counted within the MSSCA. Eighty–seven species and 8,477 individuals in the roving surveys and 107 species and 13,552 individuals in the benthic transect surveys. Eupomacentrus partitus, Thalassoma bifasciatum, Scarus taeniopterus were among the most abundant fishes in all benthic habitats. Acanthuridae, Scaridae and Holocentridae were the most abundant preferred edible fish (PEF) families totaling 77.3% of the PEF. Family Lutjanidae was not common and comprised 1.46% of PEF. Ten individuals of Lutjanus analis were observed in 2009 and 2010. Only one lionfish (Pterois volitans) was observed on the outer reef slope in July 2010 despite over 250 diver hours from April 2009 to July 2010. KEY WORDS: coral reef, fisheries management, Lutjanus analis, Virgin Islands
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CHAPTER 4 Pilot Study of Back Reef Embayments and Bays on the East End of St. Croix as post settlement habitat for juvenile grouper and snapper
INTRODUCTION The aim of this study was to assess the importance of the bays in the East End Marine Park (Fig. 4.1) in providing habitat for juvenile, mutton snapper, Lutjanus analis, the focus of this report, and the juvenile stages of other snappers (Lutjanidae) and commercially important groupers (Serranidae).
Figure 4.1. Map of the St. Croix East End Marine Park showing the management zones within the park (http://www.stxeastendmarinepark.org/maps.htm).
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Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Ontogenetic habitat shifts, from shallow inshore habitats to offshore reefs have been reported for a number of tropical fish species. Juvenile snappers have been documented to recruit to shallow coastal habitats in Cuba (Claro and Lindeman 2003) and in specific habitats such seagrass in Florida (Bortone and Williams 1986, Anon. 2008), and seagrass meadows, algal plain, coral rubble, patch reefs and back reefs in back reef embayments in St. Croix (Mateo and Tobias 2001, 2004; Adams and Ebersole 2002). Mateo and Tobias (2001, 2004) and Adams and Ebersole (2002) also documented the presence of juveniles of commercially harvested groupers (Serranidae) in the eastern embayments of St. Croix. The bays studied by Mateo and Tobias (2001, 2004) and Adams and Ebersole (2002) were incorporated into the St. Croix East End Marine Park (Quinn 2010) in 2003 to in part protect fish nursery habitat. The focal management area for the park, when it was established, was the bays. The management areas were selected based on public workshops that included representatives of commercial and recreational fishers, scuba dive organizations, government agencies, and nonprofit organizations. The bays were acknowledged as important nursery areas for commercially harvested fish and queen conch. It was also acknowledged that they had been overfished because of their relatively limited area and easy access. Most of the shallow water bays have been zoned no-take areas, except for several areas which permit recreational line fishing: a strip along the shoreline throughout the park; Teague and Cotton Garden Bay, which includes Cramer Park, a public park, on the north shore; and part of Turner Hole on the south shore (Fig. 4.1). We chose to study two bays in the East End Marine Park which are subject to the parks no take provisions and will afford substantial protection once the regulations come into force. Two types of bays are found within the park: 1) back reef embayments which consist of a shallow lagoon protected by an emergent reef, usually with shallow channels through which tidal and wind driven currents flow and 2) open bays with similar habitats but no emergent reef protecting them from heavy seas. In 2009, four bays were surveyed in the park. Two, Robin Bay, a back reef embayment and Chenay Bay, an open bay (Fig. 4.2) were selected for more intensive study. Robin Bay was previously studied by Mateo and Tobias (2004). In their monthly, one year study of six east end bays, they recorded juveniles of six species of Lutjanidae and five species of commercially important Serranidae, but only the yellowtail snapper was recorded in reasonably high density. Also, only two mutton snapper juveniles were recorded, both in a single bay, Turner Hole. They primarily sampled seagrass meadows (80% of samples), but reported the highest densities of juvenile fish in structured habitats, e.g. coral rubble and patch reefs. Less than 4% of their samples were taken in these structured habitats. Also, they did not survey the reefs behind the reef crest (back reefs). This habitat type was sampled by Adams and Ebersole (2002) in back reef embayments in St. Croix, but they did not sample Robin Bay. Based the results of these authors and our own observations, the back reef of Robin Bay, was sampled along with seagrass and sand habitats in Robin Bay. Chenay Bay, an open bay, had not previously been sampled. It was chosen because it contained habitats found in the embayments, e.g. shallow seagrass meadows, sand, and coral rubble, and also contained deeper water seagrass and pavement habitats. Being an open bay, there were potentially fewer impediments to larval recruitment, i.e. no emergent reef potentially blocking recruits from entering the bay. It did not contain back reef habitat because there were no emergent reefs fronting the bay.
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In 2010, the inshore beachrock habitat on the western shoreline of St. Croix south of Frederiksted was searched for juvenile snapper and grouper. The west end of St. Croix is down current of almost the entire St. Croix shelf and was considered a potential "sink" for snapper and grouper larval settlement.
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Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
MATERIALS AND METHODS Four bays were surveyed to determine the range of shallow water habitat types in each bay, check for the presence of early and later stage juvenile snapper and grouper, and to select bays and habitats to more intensively survey. Robin Bay and Rod Bay on the south shore and Chenay Bay (Fig. 4.2) on the north shore were surveyed using snorkels and underwater scooters and Cotton Garden Bay (Fig. 4.2) was surveyed with snorkels only. Two bays, Chenay Bay on the north shore and Robin Bay on the south shore (Fig. 4.1), were selected for further study. In these bays, representative sites were selected based on the snorkel surveys and NOAA NOS habitat maps (Kendall et al 2001) (Fig. 4.3). Surveys were conducted during summer (July 2009), one of the two seasons (summer and fall) with the highest fish density (Mateo and Tobias 2004; Adams and Ebersole, 2002) and highest species diversity (H') and eveness (J') (Mateo and Tobias, 2004).
Figure 4.2. Google Earth image of the East End of St. Croix showing location of Rod Bay and Robin Bay on the south shore, Chenay Bay (west) and Cotton Garden Bay (east) on the north shore. Selected representative habitat types in Chenay Bay and Robin Bay were more intensively surveyed. The location of each surveyed site was marked using a Garmin GPSmap 76Cx. Coordinates for the two deeper water sites in Chenay Bay (CBP1 and CBSG2) were obtained by recording the coordinates as divers entered the water. Shallow water sites sampled using snorkeling were marked by towing the Garmin GPS in tracking mode attached to a float and determining the GPS location of the site from the track (remainder of sites).
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At each of the intensively surveyed sites (six in Chenay Bay and three in Robin Bay), five 10m transect lines were deployed with the exception of CBSG3 where six transect lines were deployed and six fish surveys, but only five benthic surveys, were conducted. Ten quadrats (0.25 m2) were photographed using an Olympus SW1030 digital camera along five 10m transect lines in each habitat. The habitat in each quadrat was analyzed by estimating the percent cover of the major habitat components and averaging the results for the ten quadrats from each transect and averaging the mean for each transect at each site. Fish species and phase were recorded two meters either side of the transect line. Fifteen minute roving fish censuses were also conducted at each of the above sites. In Chenay Bay, a seventh site, CBBR7 - intertidal beach rock, was surveyed during a snorkel swim. Two other sites, the eastern end of Cotton Garden Bay and the shallow inshore coastal beach rock habitat south of Frederiksted, were searched for snapper and grouper juveniles using snorkel for and, for the Frederiksted habitat, scuba. Chenay Bay Chenay Bay, located on the north coast of St. Croix, is a relatively large bay with extensive seagrass, sand, and colonized pavement habitat. Seven sites, representative of seven different habitats were surveyed. Table 4.1 provides the location, depth and description of each site. Figure 4.3 shows the NOAA NOS habitat map of Chenay Bay. Five of the six habitats mapped by NOAA were surveyed. The only habitat not surveyed was the deeper water patchy seagrass 70-90% habitat. CBP1 and CBSG2 were deeper water sites (7.6 - 9 m depth) accessed by boat and surveyed using scuba (Fig. 4.3). The other sites were shallow water sites accessed from shore and surveyed by snorkeling (Fig. 4.4 & 4.5).
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Table 4.1. Summary of sites surveyed in Chenay Bay, north shore, St. Croix, U.S. Virgin Islands. Site Code
Date of Survey
Latitude (N)*
Longitude (S)*
Depth (m)
NOAA NOS Habitat Category
CBP1
14 July 2009
17.7792
-64.66176
7.6
Reef/Colonized Pavement
CBSG2
15 July 2009
17.77343
-64.66062
9.0
Seagrass Patchy - 30-50%
CBSG3
16 July 2009
17.76027
-64.66076
1.9
Continuous seagrass
CBSG4
24 July 2009
17.76046
-64.66175
2.0
Patchy Seagrass - 10-30%
CBSG5
24 July 2009
17.76102
-64.66183
2.0
Patchy Seagrass - 10-30%
CBP6
25 July 2009
17.76287
-64.66138
2.0
Reef/Colonized Pavement
CBBR7
28 July 2009
17.909708
-64.66048
Intertidal
Reef/Colonized Bedrock
Description of Site Deeper water: Pavement with turf and macroalgae, sponges, and some shallow cracks and crevasses Deeper water: Seagrass on sand with many sea pussys (Meoma ventricosa) Shallow water: >75% seagrass (primarily Thalassia testudinum (turtle grass) with some Syringodium filiforme (manatee grass). Shallow water: Primarily sand with some coral rubble. Seagrass <1% Shallow water: 10-30% seagrass on sand Shallow water: Pavement with consolidated coral rubble (primarily dead Porites branches and slabs of dead Acropora palmata). Rubble rises about 1m above surrounding pavement and sand. Intertidal: Beach rock with undercut ledge. Sand and seagrass seaward of beach rock.
* The coordinate system used is WGS84. Coordinates mark the approximate center of the area covered in transect surveys.
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Chenay Bay
Figure 4.3. NOAA NOS habitat map encompassing Chenay Bay showing habitat breakdown.
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Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Figure 4.4. Google Earth map showing approximate locations of sample sites.
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Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Figure 4.5. Google Earth map showing location of survey sites in inner Chenay Bay. Robin Bay and Rod Bay On the south shore, initially, snorkel surveys were conducted in Rod Bay and Robin Bay (Fig. 4.2), using underwater scooters, to get an overview of the habitat in the bays and the distribution and abundance of post settlement and juvenile snapper and grouper juveniles. Photographs were taken of the habitats, especially habitats with juvenile snapper. Three sites representative of the main habitat types in Robin Bay were more intensively surveyed using the transect/quadrat method described above. Table 4.2 lists the site coordinates, depth and briefly describes the habitat. Figure. 4.6 is the NOAA NOS habitat map for Rod and Robin Bays. Three of the six habitats mapped by NOAA NOS were intensively surveyed. Five of the six were surveyed by scooter transect. The only habitat not surveyed was the Reef/Spur and Groove which was too exposed to wave action to survey. The three sites intensively surveyed are shown on a Google Earth image (Fig. 4.7) and a Google Maps image (Fig. 4.8). The latter has much better resolution than the former.
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Table 4.2. Summary of sites surveyed in Robin Bay, south shore, St. Croix, U.S. Virgin Islands on July 13, 2009. Site Code
RB1
RB2 south end of survey site RB2 north end of survey site
Latitude (N)*
Longitude (S)*
Depth (m)
NOAA NOS Habitat Category
17.72472
-64.63176
2
Seagrass/Contin uous
17.72454
-64.63182
2
Seagrass Patchy 10-30%
17.7246
-64.63182
2
Seagrass Patchy 10 -30%
RB3- 1 Transects 1-3
17.72339
-64.63167
2
Reef/Linear Reef
RB3- 2 Transects 4&5
17.72316
-64.63165
2
Reef/Linear Reef
Description of Site Continuous seagrass: >75% seagrass - primarily Thalassia testudinum (turtle grass) with some Syringodium filiforme (manatee grass). Sand patch (<10% seagrass) primarily S. filiforme. Sand patch (<10% seagrass) primarily S. filiforme. Back reef habitat: coral reef located behind the reef crest primarily dead coral reefs surrounded by pavement, coral rubble, seagrass (primarily T. testudinum) and/or sand. Back reef habitat as above.
* The coordinate system used is WGS84. Coordinates mark the approximate center of the area covered in transect surveys.
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Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Figure 4.6. NOAA NOS habitat map of Robin and Rod Bays, south coast St. Croix.
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Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Figure 4.7. Robin Bay, St. Croix with the location of the three sites surveyed marked.
Figure 4.8. Robin Bay, St. Croix with using the new Google Maps image with the three sites surveyed marked by the approximate coordinates. This Google Maps image has better habitat resolution.
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RESULTS Chenay Bay A variety of habitat was searched for newly settled and juvenile grouper and snapper. Two habitats characteristic of the deeper water habitats in the outer part of Chenay Bay as shown on NOAA NOS habitat maps (Fig. 4.3) were more intensively sampled. Six habitats in the inner part of the bay which characterized habitats mapped by NOAA NOS and were observed during scooter surveys were also more intensively sampled. Habitat Table 4.3 provides a summary of the cover of various habitat components in the different types of habitats. Coral cover was highest at CBP1 (Fig. 4.9), though coral only comprised 0.6% of the total coral cover. Eleven scleractinian corals and one Millepora (M. alcicornis) were recorded. Siderastrea siderea (number of colonies: 22), Diploria strigosa (19), Porites astreoides (15), and Montastrea cavernosa (14) had the highest number of colonies recorded. A variety of algal genera were recorded, primarily the phaeophytes: Dictyota, Turbinaria, Padina and Saragassum; the rhodophyte Amphiroa, Chlorophyte algae: Penicillus, Neomeris, and Avrainvillea; and Cyanobacteria. The gorgonians Briarium asbestinum and Gorgonia ventalina were present but rare. The deeper water seagrass habitat CBSG2 (Fig. 4.10) was a sand and seagrass/algal habitat. Thalassia testudinum and Syringodium filiforme were present in all five transects. Cyanobacteria and Chlorophyta (e.g. Halimeda and c.f. Avrainvillea) were the predominant algal taxa. Table 4.3. Mean percent cover of various biotic and abiotic habitat components at six sites in Chenay Bay, St. Croix, U.S. Virgin Islands. Site CBP1 CBSG2 CBSG3 CBSG4 CBSG5 CBP6
Sand Covered Pavement 41.1 0 0 0 0 0
Sand 0 60.0 17.0 77.00 57.2 12.3
Rubble* 11.9 2.7 0.9 21.42 0.9 72.1
Algae 38.0 14.9 12.5 1.28 6.1 15.0
Seagrass
Sponge
6.4 21.6 69.5 0.20 35.7 0
2.0 0.3 0.1 0 0 0
Coral 0.6 0.1 0.0 0 0 0.2
Other 11.9 0.4 0 0 0 0.3
*Rubble is defined as "low relief, calcareous structure composed primarily of conch shells or dead/dying coral fragments that are not attached to the substrate" (Adams and Ebersole 2002). The sites in the inner bay ranged from the intertidal beachrock habitat to continuous seagrass with >75% seagrass cover. The sandy beach in Chenay Bay is underlain by beachrock. In certain locations the beachrock is exposed to a depth of about 0.5m and highly eroded with pits and crevasses. These features and an undercut ledge create habitat for a variety of fish,
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Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Figure 4.9. Representative photos showing the type of habitat found in CBP1 in the outer part of Chenay Bay, St. Croix, USVI. Square is 0.25m2.
Figure 4.10. Representative photos of habitat found in CBSG2 in the outer part of Chenay Bay. Square is 0.25m2. especially juvenile snapper. Snapper and grouper counts were carried out along the length of the exposed beachrock habitat - approximately 75m. Visibility was too poor to obtain photos of this habitat. The sites in the inner bay ranged from the intertidal beachrock habitat to continuous seagrass with >75% seagrass cover. The sandy beach in Chenay Bay is underlain by beachrock. In certain locations the beachrock is exposed to a depth of about 0.5m and highly eroded with pits and crevasses. These features and an undercut ledge create habitat for a variety of fish, especially juvenile snapper. Snapper and grouper counts were carried out along the length of the exposed beachrock habitat - approximately 75m (15 minute census). Visibility was too poor to obtain photos of this habitat. The three sand/seagrass habitats surveyed, represented the variety of sand habitats in the inner portion of the bay. The highest seagrass density, primarily T. testudinum, recorded was 70% in CBSG3 (Fig. 4.11). Algae, primarily Chlorophyta (Penicillus, Halimeda, and Caulerpa
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Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Figure 4.11. Inner Chenay Bay, St. Croix, USVI - CBSG3, continuous seagrass habitat with >75% cover of seagrass.
Figure 4.12. Sand and sand/coral rubble habitat characteristic of CBSG4 in inner Chenay Bay, St. Croix, USVI. Square is 0.25m2.
Figure 4.13. Inner Chenay Bay, St. Croix USVI - Photos representative of CBSG5 showing patchy seagrass habitat with seagrass comprising 30-50% cover. Square is 0.25m2. 184
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
prolifera) comprised 13% of the biota. The only coral recorded was one colony of P. furcata. CBSG4 was primarily a sand habitat with coral rubble (Fig. 4.12). Seagrass, primarily T. testudinum, comprised <1% of the habitat. CBSG5 was primarily sand (57%) and seagrass (36%) habitat with 6% algae (Fig. 4.13). Both T. testudinum and S. filiforme were present. The algal component was primarily Halimeda and Penicillus with some Cyanobacteria. The only consolidated coral rubble habitat surveyed was CBP6 (Fig. 4.14). This site represented the large hard bottom/coral rubble habitat that extended north/south in the center of the inner bay. Consolidated coral rubble comprised 72% of the habitat. The rubble was primarily comprised of dead Porites branches and slabs of A. palmata cemented to limestone. Algae, primarily Phaeophyta , Dictyota, Turbinaria, Saragassum and Padina with some Rhodophyta and Chlorophyta, covered 15% of the bottom and sand 12%. Sea urchins, including Diadema antillarum, were common.
Figure 4.14. Photos of consolidated coral rubble habitat characteristic of CBP6 in inner Chenay Bay, St. Croix, USVI. Square is 0.25m2. Fish Surveys Twenty-eight species of fish were recorded in roving fish census and 10m transect surveys at two sites in outer Chenay Bay (Table 4.4). At the these two sites, the largest number of species and individuals were in the pavement habitat (CBP1). Only two commercially harvested serranid species were recorded in the outer part of the bay, both at the CBP1 site: 15 juvenile / subadult coneys (Cephalopholis fulvus) and four red hind (Epinephelus guttatus) (Table 4.4). Other serranids reported were the lantern bass (Serranus baldwini) and the harlequin bass (S. trigrinus). No snappers, adult or juvenile, were recorded. Five parrotfish species, three of which are commercially harvested (redband, redtail and yellowtail) were recorded. Most of the parrotfish were juvenile and initial stages (Table 4.4). In contrast to outer Chenay Bay, no commercially harvested groupers, juvenile or adult, were recorded, but snappers were (Tables 4.5 and 4.6). All snappers recorded were juveniles or subadults. They were present in four of the five habitats surveyed. The only habitat they were not recorded was CBSG4 which was predominately a sand habitat with some buried coral rubble 185
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
and a very minor seagrass component. Juvenile snapper look for structure and while present in CBSG3, >75% seagrass, they were mostly in locations with dead conch shells, coral rubble, and blowouts. The one time juvenile snapper were seen away from these habitats, they were swimming rapidly through the seagrass in a small group. Size varied among the snapper species in the roving fish surveys with lane snapper ranging in size from 1cm (semi-transparent) - 5cm, yellowtail 1.5 - 9 cm, mahogany 7 - 9cm, and gray and schoolmaster 14 cm. The highest numbers (22 individuals) and species diversity (5 species) of snappers were recorded along the beachrock (CBBR7) (Table 4.5). The area surveyed included a seagrass ledge (blow out) immediately adjacent to a section of the beachrock where a small school of mahogany snapper were seen. The continuous seagrass habitat (CBSG3) had the second highest number of individual snappers (18) and species diversity (3) (Table 4.5). Yellow tail snapper were most common in CBSG3 (>75% seagrass habitat) where they comprised 67% of the snapper recorded in this habitat. They were also present but much less common in the beachrock habitat. Mostly small labrids, pomacentrids and scarids were recorded in transect surveys in inner Chenay Bay. The only commercially harvested parrotfish recorded was the striped parrotfish (Scarus iserti) (Table 4.6). All S. iserti were juvenile or small initial stages. Almost equal numbers of juvenile and adult Acanthurus chirurgus/bahianus were recorded.
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Table 4.4. Fish species, including maturity stages, recorded at the two outer Chenay Bay sites. Family Acanthuridae Balistidae Carangidae Dactylopteridae Holocentridae Holocentridae
Scientific name Acanthurus chirurgus/bahianus Balistes vetula Trachinotus falcatus Dactylopterus volitans Holocentrus sp.
Common name Surgeon - Doctor or Ocean Queen triggerfish Permit Flying gurnard Squirrelfish adscensionis or rufus
Labridae
Halichoeres bivittatus
Slippery dick
Labridae
Halichoeres garnoti
Yellowhead wrasse
Labridae
Halichoeres maculipinna
Clown wrasse
Labridae Labridae
Halichoeres poeyi Halichoeres radiatus
Blackear wrasse Puddingwife
Labridae
Thalassoma bifasciatum
Bluehead wrasse
Labridae
Xyrichtys martinicensis
Rosy razorfish
Malacanthidae
Malacanthus plumieri
Monocanthidae Monacanthidae Mullidae Ostraciidae Pomacentridae Scaridae
Monacanthus ciliatus Pseudupeneus maculatus Lactrophrys sp. Eupomacentrus partitus Sparisoma atomarium
file fish unidentified Fringed filefish Spotted goatfish Trunkfish Bicolordamselfish Greenblotch parrotfish
Scaridae
Sparisoma aurofrenatum
Redband parrotfish
Scaridae
Sparisoma chrysopterum
Redtail parrotfish
Scaridae
Sparisoma radians
Bucktooth parrotfish
Sand tilefish
Stage adult juvenile juvenile juvenile adult juvenile terminal initial intermediate juvenile intermediate juvenile intermediate juvenile terminal juvenile/initial male juvenile unreported adult juvenile
juvenile
juvenile initial/juvenile intermediate juvenile terminal initial terminal
187
CBP1 Roving Fish Survey
CBP1 Transects
9 40 1 1 0 15 6 0 0 0 0 0 0 0 0 0 0 0 0 0 1 2 0 0 2 5 0 0 0 0 0 5 7 0
6 0 0 0 0 0 0 0 0 0 1 2 1 0 0 3 68 0 0 0 0 0 0 0 0 0 11 16 1 0 2 0 0 0
CBSG2 Roving Fish Survey 27 0 0 0 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 2 0 0 1 0 0 11 0 0 0 0 0
CBSG2 Transects 0 6 0 0 0 0 0 1 4 6 0 0 0 1 0 0 0 1 2 1 0 0 0 1 1 0 0 6 0 2 1 0 0 1
Total
42 46 1 1 1 15 6 1 4 6 1 2 1 1 1 3 68 1 2 1 1 2 2 1 3 6 11 22 12 2 3 5 7 1
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Family
Scientific name
Common name
Tetraodontidae
Sparisoma rubripinne
Yellowtail parrotfish
Serranidae Serranidae Serranidae Serranidae Tetraodontidae
Cephalopholis fulvus Epinephelus guttatus Serranus baldwini Serranus tigrinus Sphoeroides spengleri
Coney Red hind Lantern Bass Harlequin Bass Bandtail puffer Total number fish Total number of species
Stage
CBP1 Roving Fish Survey
CBP1 Transects
CBSG2 Roving Fish Survey
CBSG2 Transects
0 0 10 15 4 0 0 0 123 12
4 0 0 0 0 3 2 0 120 10
0 8 0 0 0 0 0 0 51 7
0 0 0 0 0 1 0 1 36 9
juvenile initial/juvenile juvenile juvenile juvenile adult
Table 4.5. Snapper and commercially important grouper species and life stages recorded at the five sites surveyed during 15 minute roving fish surveys in the inner part of Chenay Bay, St. Croix, USVI. Family Lutjanidae Lutjanidae Lutjanidae Lutjanidae Lutjanidae Serranidae
Scientific name Lutjanus apodus Lutjanus griseus Lutjanus mahogoni Lutjanus synagris Ocyurus chrysurus
Common name Schoolmaster snapper Gray snapper Mahogany snapper Lane snapper Yellowtail snapper
Stage juvenile juvenile juvenile juvenile juvenile
CBSG3 3
Total number fish Total number of Lutjanidae species
18 3
CBSG4
3 12
188
CBSG5 4
CBP6
CBBR7 2 1 13 4 2
0 0
22 5
4
0 0
9 2
Total 9 1 13 11 14 0 48 5
Total
4 8 10 15 4 4 2 1 330 28
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Table 4.6. Fish species and life stages recorded in transect surveys at four sites in inner Chenay Bay, St. Croix, USVI. Family Acanthuridae Bothidae Chaetodontidae
Labridae
Scientific name Acanthurus chirurgus/bahianus Bothus sp. Chaetodon capistratus
Halichoeres bivittatus
Common name Surgeon - Doctor or Ocean Flounder Foureye butterflyfish
Slippery dick
Labridae
Halichoeres garnoti
Yellowhead wrasse
Labridae
Halichoeres maculipinna
Clown wrasse
Labridae
Halichoeres poeyi
Blackear wrasse
Labridae
Thalassoma bifasciatum
Bluehead wrasse
Lutjanidae Mullidae
Ocyurus chrysurus Pseudupeneus maculatus
Yellowtail snapper Spotted goatfish
Pomacentridae
Eupomacentrus leucostictus
Beaugregory
Pomacentridae
Eupomacentrus partitus
Scaridae
Scarus iserti
Bicolordamselfish Small unidentified parrotfish Striped parrotfish
Scaridae
Sparisoma atomarium
Greenblotch parrotfish
Scaridae
Sparisoma radians
Bucktooth parrotfish
Serranidae Serranidae Synodontidae
Serranus tabacarius Serranus tigrinus Synodus intermedius
Tobaccofish Harlequin Bass Sand diver
Scaridae
Stage adult juvenile juvenile terminal intermediate terminal/initial intermediate initial/juvenile juvenile unreported intermediate juvenile terminal juvenile intermediate intermediate juvenile/initial juvenile juvenile adult juvenile
juvenile/initial unreported initial - juvenile juvenile initial juvenile unreported adult adult
189
CBSG3 0 0 0 2 0
CBSG4 0 3 1 0 0
CBSG5 0 0 0 0 0
CBSG6 8 6 0 0 1
Total 8 9 1 2 1
0
1
0
13
14
1
4
1
0
6
6 0 1 3 0 0 1 0 0 2 0 0 7 0
4 0 0 0 0 0 1 0 0 0 2 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0
2 2 0 0 1 2 1 5 8 0 0 5 7 3
12 2 1 3 1 2 3 5 8 2 2 5 14 3
5
2
0
0
7
0 1 0 2 4 1 0 0 0 0
0 0 4 2 0 0 0 0 0 0
3 0 0 2 0 0 0 0 0 0
0 0 0 1 0 0 1 1 2 1
3 1 4 7 4 1 1 1 2 1
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Family Tetraodontidae
Scientific name Canthigaster rostrata
Common name Sharpnose puffer
Stage
Total number fish Total number of Lutjanidae species
190
CBSG3 0
CBSG4 0
CBSG5 1
CBSG6 0
Total 1
44 9
24 7
7 3
70 12
145 20
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Robin Bay Habitat Robin Bay is a large bay located in the drier east end of the island. The bay is protected by an emergent reef that extends from Grass point (the eastern end of Rod Bay) to the western end of Great Pond Bay (Fig. 4.2). It harbors a variety of habitats including dense seagrass (primarily in the inner two-thirds of the bay), sand, consolidated coral rubble, patch reefs, and coral reef (back reef). The latter three habitats are predominately located in the outer third of the bay behind the reef crest. The back reef and patch reefs are largely dead today, but it is still clear from the skeletons of the corals and the remaining living tissue, that three genera (branching Porites, Montastrea annularis, and Acropora palmata) were the predominant reef builders in the back reef. Today, most of these large, formerly monotypic reefs are covered in algae (calcareous, turf and macro algae). Coral cover is low (Table 4.7) and, except for M. annularis, predominately of species, other than those that originally constructed the reefs. Table 4.7. Mean percent cover of various habitat components at three sites in Robin Bay, St. Croix, U.S. Virgin Islands. Sites were sampled on July 13, 2009. Sand
Rubble
Algae
Seagrass
Sponge
Coral
Dead Coral Reef
-
15.5 (+7.4)
0.0
1.6 (+0.5)
82.8 (+7.7)
0.0
0.0
0.0
0.11 (+0.2)
-
97.4 (+3.3)
0.0
0.7 (+0.6)
2.0 (+3.2)
0.0
0.0
0.0
0.0
-
3.3 (+4.0)
1.1 (+0.8)
25.0 (+7.4)
6.3 (+5.5)
0.2 (+0.4)
2.0 (+1.5)
62.0 (+9.7)
0.12 (+0.2)
Site RB1 x (SD) RB2 x (SD) RB3 x (SD) 1 2
Other
"Other" in dense seagrass was one Echinometra ventricosa (West Indian sea egg). "Other" in back reef habitat was Briarium asbestinum (corky sea fingers).
RB1 was almost exclusively as seagrass habitat (Table 4.7) dominated by Thalassia testudinum (turtle grass) with Syringodium filiforme (Fig. 4.15). No coral rubble was recorded at this site. However, seagrass extends into the back reef crest habitat (RB3) and coral rubble becomes increasingly common closer to the reef. One Echinometra ventricosa was recorded in the quadrats. This species was common in seagrass in the middle of the bay. Algae was only a minor component of the seagrass community. The primary algal species recorded was Penicillus capitatus/ lamourouxii (species indistinguishable in photographs). RB2 was almost exclusively sand (Table 4.7) with a few strands of S. filiforme (Fig. 4.15). Two queen (Strombus gigas) and eight milk (S. costatus) conch (Fig. 4.15) were recorded in the sand patch during a timed 15 minute swim. An egg mass (12cm in length) and a milk conch laying eggs was observed.
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Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Figure 4.15. Left: Dense seagrass habitat (similar to RB1) near back reef crest community (RB3) dominated by Thalassia testudinum. As shown in this photo, coral rubble is present in seagrass beds immediately behind the back reef crest. Right: Milk conch (Strombus costatus) n the sand patch surveyed (RB2). RB3, the back reef habitat, was the most diverse of the three habitats (Table 4.7). It harbored a wide range of largely dead reefs, each predominately composed of a single species. The reefs consisted of the skeletons of Acropora palmata (Fig. 4.16), A. cervicornis rubble (Fig. 4.17), Porites furcata (Fig. 4.18), Montastrea annularis and M. faveolata (Fig. 4.19). These previously, predominately single species reefs, are now being colonized by a variety of coral species. The reef building species that formed these reefs are not substantially recovering and coral cover is low (2%) (Table 4.8). No acroporids and only two colonies of M. faveolata were present in quadrats. The most common species of coral recorded in quadrats was Montastrea annularis (16 colonies) and Agaricia agaricites (14) (Table 4.8). Most colonies of M. annularis were small or exhibited partial mortality, resulting in up to 15 remnants of what was clearly once a much larger colony (Fig. 4.20). No coral disease was observed.
192
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Figure 4.16. Back reef crest habitat in Robin Bay, St. Croix (RB3): Dead, in situ Acropora palmata reef. These A. palmata reefs in Robin Bay are slowly eroding and breaking up. The dead branches provide settlement sites for other coral species such as the Diploria strigosa and gorgonian sea fans. Live colonies of A. palmata were extremely rare.
Figure 4.17. Rubble habitat near back reef in Robin Bay, St. Croix (RB3): Former Acropora cervicornis reef, now a branching coral rubble field on pavement and sand.
193
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Figure 4.18. Back reef crest habitat in Robin Bay, St. Croix (RB3) (above): Large Porites furcata reef (right) with very little living tissue remaining on branches. Smaller isolated P. furcata patch reef (left) located in seagrass bed shoreward of back reef with about half of the colony alive. Figure 4.19. Back reef crest habitat in Robin Bay, St. Croix (RB3) (right): Montastrea annularis (upper right photo) and M. faveolata patch reefs (lower right photo) frequently showed partial colony mortality. M. annularis was the species most frequently recorded in quadrats. Scooter used in transects (bottom photo).
194
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Table 4.8. Back reef crest habitat in Robin Bay, St. Croix (RB3): Coral species and number of colonies recorded in quadrats in RB3. Coral Species
Number of colonies*
Hydrozoa Millepora alcicornis Scleractinia
1
Agarica agaricites A. tenuifolia Diploria strigosa Montastrea annularis Porites astreoides P. porites S. siderea
12 (14) 1 1 16(64) 2 5 2
Figure 4.20. Back reef crest habitat in Robin Bay, St. Croix (RB3): partial mortality of Montastrea annularis colony.
*Numbers in parentheses count remnants (partial mortality) as separate colonies. Fish Surveys
A total of 31 fish species and 273 individuals were recorded in the Robin Bay surveys (Table 4.9). Most of species, especially the larger species, were represented by juveniles (Table 4.10). The number and species of fish were very low in the dense seagrass and sand habitats in Robin Bay (RB1 and RB2) (Table 4.9). No snappers or groupers, adult or juvenile, were recorded in these two habitats. Fish abundance and numbers of species were much higher in the back reef areas (RB3) (Table 4.9). The families with the highest density in RB3 transects were the Labridae (wrasses) and Pomadasyidae (grunts). Juveniles of four species of Lutjanidae (snappers) were recorded along with one adult serranid, Cephalopholis fulvus (coney). The predominant life stage for most species of larger fish size of adults >20cm) were juveniles or sub adults (1.5-15cm in length). Sub adults of the schoolmaster snapper (Lutjanus apodus) in were the largest snappers recorded with a maximum length of about 15 cm, but all had bars on their back, which is characteristic of juveniles (Humann and Deloach 2002). During scooter and snorkel surveys conducted in Rod Bay on the July 3 - 4, 2009 and in Robin Bay on July 6, 2009 only one mutton snapper juvenile (15 cm) was observed. Juvenile lane, yellowtail, and mahogany snapper were common, invariably associated with the dead coral reefs of the outer bay in Robin Bay and Rod Bay or the small largely dead Porites patch reefs in inner Rod Bay (Fig. 4.21 and 4.22). No juvenile or adult grouper were observed. The bluehead wrasse (Thalassoma bifasciatum) was common in the back reef habitats. The juvenile/initial phase is different in the back reef embayments than in the Mutton Snapper Seasonal Closed Area (MSSCA). It is almost exclusively yellow backed without a prominent black stripe in the MSSCA and white or yellow backed with prominent black mid-body stripe and white belly in Robin Bay, a back reef embayment. The white phase is totally absent in the MSSCA.
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Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Figure 4.21. Rod Bay, St. Croix: Juvenile lane snapper (Lutjanus synagris), possibly a juvenile schoolmaster snapper (L. apodus), blue tang (Acanthurus coeruleus), and grunts (Haemulon spp.) in a dead Porites patch reef.
Figure 4.22. Rod Bay, St. Croix: Juvenile mahogany (Lutjanus mahogoni) and schoolmaster snapper (L. apodus), school of blue tang (Acanthurus coeruleus), and several squirrelfish (Holocentrus sp.) on largely dead reef in outer part of the bay
196
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Table 4.9. Robin Bay: Summary of species and life stages of fish observed at three sites in Robin Bay, St. Croix, USVI. Transect surveys were conducted on July 13, 2009 and the roving fish surveys on August 8, 2009. Family
Acanthuridae
Acanthuridae Carangidae Chaetodontidae Holocentridae
Scientific name Acanthurus chirurgus/bahia nus Acanthurus coeruleus Caranx ruber Chaetodon capistratus
Holocentridae
Holocentrus sp. Holocentrus adscensionis Holocentrus rufus Myripristis jacobus
Labridae
Bodianus rufus
Holocentridae Holocentridae
Labridae
Labridae Labridae Labridae
Halichoeres bivittatus
Halichoeres maculipinna Halichoeres poeyi Halichoeres radiatus
Common name Surgeon Doctor or Ocean Blue Tang Bar jack Foureye butterflyfish Squirrelfish unidentified Squirrelfish Longspine squirrelfish Blackbar soldierfish Spanish hogfish
Slippery dick
Clown wrasse
Stage adult
RB1 Roving Fish Census 0
0
RB2 Roving Fish Census 0
RB1 Transects
0
RB3 Roving Fish Census 0
RB2 Transects
RB3 Transects
Total
4
4
juvenile
0
0
0
0
4
4
8
adult
0
0
0
0
0
1
1
0
0
0
0
0
2
2
0
0
0
0
0
3
3
0
0
0
0
0
1
1
0
0
0
0
0
1
1
0
0
0
0
0
10
10
0
0
0
0
0
3
3
0
0
0
0
0
1
1
0
0
0
0
0
1
1
0
1
0
1
0
0
2
0
0
0
0
0
7
7
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
9 2 2
9 2 2
0
0
0
0
0
1
1
0
0
0
0
0
3
3
juvenile
juvenile terminal Intermediate terminal/initial Intermediate initial/juvenile juvenile intermediate juvenile
Blackear wrasse
unreported
Puddingwife
juvenile
197
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Family
Scientific name
0 0 0
RB3 Roving Fish Census 0 0 0
3
1
2
0
6
0
0
0
1
0
1
0
0
0
0
3
0
3
0
0
0
0
3
0
3
juvenile
0
0
0
0
0
4
4
unreported
0
0
0
0
0
10
10
Brown chromis
adult
0
0
0
0
0
1
1
Beaugregory
adult juvenile unreported
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
4 3 6
4 3 6
adult
0
0
0
0
0
3
3
0
0
0
0
1
0
1
unreported
0
0
0
0
3
1
4
4-6" stage unidentified
0
0
0
0
0
50
50
French grunt
0
0
0
0
0
19
19
Cottonwick
juvenile
0
0
0
0
0
1
1
White grunt
juvenile unreported
0 0
0 0
0 0
0 0
0 0
13 5
13 5
Common name
Labridae
Thalassoma bifasciatum
Bluehead wrasse
Labridae
Xyrichtys martinicensis
Rosy razorfish
Lutjanidae
Lutjanus apodus
Lutjanidae Lutjanidae Lutjanidae Mullidae Pomacentridae Pomacentridae
Lutjanus mahogoni Lutjanus synagris Ocyurus chrysurus Pseudupeneus maculatus Chromis multilineata Eupomacentrus leucostictus
Pomacentridae
Microspathodon chrysurus Stegastes
Pomacentridae
Stegastes fuscus
Pomadasyidae
Haemulon flavolineatum
Pomacentridae
Pomadasyidae Pomadasyidae
Haemulon melanurum Haemulon plumieri
Schoolmaster snapper Mahogany snapper Lane snapper Yellowtail snapper Spotted goatfish
Yellowtail damselfish Damselfish Dusky damselfish
Stage terminal intermediate juvenile/initial
RB1 Roving Fish Census 0 0 0
unreported juvenile juvenile juvenile
198
0 0 0
RB2 Roving Fish Census 0 0 0
0
0
0
RB1 Transects
RB2 Transects
RB3 Transects
Total
1 13 10
1 13 10
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Family
Scientific name
Pomadasyidae
Haemulon sp.
Scaridae Scaridae Scaridae Scaridae Serranidae
Scarus iserti Sparisoma aurofrenatum Sparisoma radians Sparisoma viride Cephalopholis fulvus
Common name
0
RB3 Roving Fish Census 0
0
0
0
19
19
0
0
0
0
6
6
0 0
1 0
0 0
0 0
0 3
3 0
4 3
juvenile
0
0
0
0
5
5
adult
0
0
0
0
2
0
2
0
2
3
2
21
245
273
0
2
1
2
9
27
31
Stage juvenile
Striped parrotfish Redband parrotfish Bucktooth parrotfish Stoplight parrotfish Coney
RB1 Roving Fish Census 0
juvenile/initial juvenile juvenile unreported
Total number fish Total number of species (excluding fish only identified to genus)
199
0
RB2 Roving Fish Census 0
0
0
0
RB1 Transects
RB2 Transects
RB3 Transects
Total
9
9
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Table 4.10. Robin Bay, St. Croix, USVI: Percentage of each developmental stage recorded based on morphology (especially Labridae and Scaridae) and/or size. Family
Scientific name
Common name
Acanthurus chirurgus/bahianus Acanthuridae Acanthurus coeruleus Chaetodontidae Chaetodon capistratus Labridae Bodianus rufus
Surgeon - Doctor or Ocean Blue Tang Foureye butterflyfish Spanish hogfish
Labridae
Slippery dick
Acanthuridae
Halichoeres bivittatus
Labridae Labridae
Halichoeres maculipinna Halichoeres poeyi Halichoeres radiatus
Labridae
Thalassoma bifasciatum
Bluehead wrasse
Lutjanidae Lutjanidae Lutjanidae Lutjanidae
Schoolmaster snapper Mahogany snapper Lane snapper Yellowtail snapper
Pomadasyidae
Lutjanus apodus Lutjanus mahogoni Lutjanus synagris Ocyurus chrysurus Haemulon flavolineatum Haemulon melanurum
Pomadasyidae
Haemulon plumieri
White grunt
Pomadasyidae Scaridae
Haemulon sp. Scarus iserti
Striped parrotfish
Labridae
Pomadasyidae
Clown wrasse Blackear wrasse Puddingwife
French grunt Cottonwick
Stage adult juvenile adult juvenile juvenile terminal Intermediate terminal/initial Intermediate initial/juvenile juvenile intermediate juvenile unreported juvenile terminal intermediate juvenile/initial juvenile juvenile juvenile juvenile 4-6" stage unidentified juvenile juvenile unreported Juvenile juvenile/initial
200
Total 4 8 1 3 1 1 2 7 9 2 2 1 3 1 13 10 1 3 3 4 50 19 1 13 5 9 19
Percent juvenile (highlighted turquoise) or intermediate (juvenile/initial) (highlighted yellow) stage 33% 67% 0% 100% 100% 5% 11% 37% 47% 50% 50% 100% 4% 54% 42% 100% 100% 100% 100% 72% 28% 100% 72% 28% 100% 100%
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Family
Scaridae
Scientific name Sparisoma aurofrenatum
Common name
Redband parrotfish
Scaridae
Sparisoma radians
Bucktooth parrotfish
Scaridae Serranidae
Sparisoma viride Cephalopholis fulvus
Stoplight parrotfish Coney
Stage
juvenile juvenile unreported juvenile adult
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Total
6 4 3 5 2
Percent juvenile (highlighted turquoise) or intermediate (juvenile/initial) (highlighted yellow) stage 100% 57% 43% 100% 100%
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Other Sites Surveyed Cotton Garden Bay, Cramer Park Eight juvenile lane/mahogany snapper, two schoolmaster snapper with juvenile markings (6-8"), and possibly one mutton snapper (reddish fins, black spot, vertical patterns on dorsal, were observed associated with coral rubble during a snorkel along the eastern shore of Cotton Garden Bay. No grouper were seen. The habitats surveyed included dense seagrass, coral rubble in seagrass and sand, and intertidal bedrock. Juvenile snapper within or adjacent to dense seagrass were exclusively associated with coral rubble (Fig. 4.23).
Figure 4.23. Cotton Garden Bay: Juvenile snapper within or adjacent to dense seagrass are invariably associated with coral rubble. Western shoreline of St. Croix The highest abundance of juvenile snapper were found on a day time snorkel on July 5, 2010 and a subsequent dive survey conducted on the morning of July 6, 2010 off the western shoreline of St. Croix in front of and south of the hotel, Sand Castle on the Beach. Large schools of a variety of species of Pomadaysidae (grunts) and schools of up to 30 snapper were common among the eroded beach rock along the shoreline in depths of <3m (Fig 4.24). The snapper schools were often mixed with larger schools of juvenile grunts. The beachrock in this location is highly eroded with undercuts and caves. It is covered with turf and macroalgae, sponges and a few scleractinian corals. The lack of coral cover is likely a function of the high surf that periodically assaults this coastline and the shifting sand that likely intermittently buries the beachrock, especially rock close to the bottom. Few large fish were observed. Most of the larger fish were grazers such as surgeonfish or an occasional large parrotfish, e.g. initial phase yellowtail parrotfish. Intermediate and initial phase slippery dicks, juvenile and initial phase bluehead wrasse, and night sergeants were common.
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Figure 4.24. Western shoreline of St. Croix. Clockwise from top left: Juvenile lane snapper (Lutjanus synagris), small snapper school adjacent to beachrock, small snapper school with two intermediate phase slippery dicks (one juvenile/initial phase and one initial/terminal phase), a school of juvenile snapper and grunts.
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Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
D ISCUSSION Nagelkerken (2002) listed 17 Caribbean reef fish species that had relatively high juvenile density in nursery habitats (mangrove and seagrass). However, when he compared fish density on islands with nursery habitat and those without nursery habitat only some of these nursery species were highly dependent on nursery habitats. Others may be dependent on nursery habitat, but results were inconclusive, and others clearly were not dependent (Nagelkerken 2002). Five snappers (Lutjanidae) were among the 17 nursery species. Two lutjanids, the schoolmaster snapper (Lutjanus apodus) and the yellowtail snapper (Ocyurus chrysurus), were considered to have a high dependence on nursery habitat with the schoolmaster having the highest density in mangroves and the yellowtail snapper in seagrass. The mutton snapper (L. analis) and the gray snapper (L. griseus) were considered to have a possible dependence on nursery habitat, with juveniles of L. analis having about equal but low density in mangrove and seagrass, while L. griseus had the highest density in mangroves. The mahogany snapper (L. mahogoni) had no dependence on nursery habitats, but was found in the highest densities mangroves. In Pacific mangroves Quinn and Kojis (1985) found few juveniles of coral reef fish inhabiting a mangrove lined estuary adjacent to coral reefs. No lutjanids, juvenile or adult, were recorded in the two habitats sampled in outer Chenay Bay or in two of the three habitats sampled (seagrass and sand) in Robin Bay. Three lutjanid species were recorded in continuous seagrass (CBSG3) in inner Chenay Bay, L. apodus, L. synagris, and O. chrysurus, in roving fish censuses. O. chrysurus was the most abundant snapper in roving fish censuses and the only lutjanid recorded in transects in the four inner bay sites. Over 85% of O. chrysurus were recorded in roving fish surveys in continuous seagrass habitat (CBSG3) (Table 4.5) and it was the only habitat in which they were recorded in transects (Table 4.6). However, in Robin Bay, O. chrysurus and the four other snapper species recorded in Robin Bay were only recorded in the back reef habitat. The continuous seagrass habitat sampled in Chenay Bay differed from the seagrass habitat sampled in Robin Bay in that rubble was intermixed among the seagrass. L. apodus and L. synagris were also recorded in 10-30% seagrass habitat (CBSG5) in roving fish surveys, but not in transects. Roving fish surveys covered a larger area than transects, and included coral rubble which was adjacent to and interspersed among the seagrass, especially along the edge of this habitat. Juveniles of all five snapper species were recorded in the highly structured beachrock habitat. Snappers, including O. chrysurus, were almost invariably associated with some structure in this study. O. chrysurus may initially recruit to seagrass or dense algae (personal obs. Kojis), but migrate to structured habitat. O. chrysurus and other snappers may prefer structured habitat associated with seagrass. While the structured habitat provides shelter and the seagrass may provide a food resource. No grouper (Serranidae) was listed among the 17 nursery species by Nagelkerken (2002). The only commercially important grouper recorded in this study were small coneys and red hind recorded as juveniles from outer Chenay Bay (Table 4.6). No commercially important grouper of any size was recorded in inner Chenay Bay or Robin Bay. In fact, the only juvenile coney (as depicted and described in Humann and Deloach (2002)) recorded in this entire study was in hard bottom algae/invertebrate habitat (ALIN) in the Mutton Snapper Seasonally Closed Area. 204
Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
Mateo and Tobias (2001, 2004) had similar results to our study in their study of six bays on the east end of St. Croix. They recorded a total of six snapper species (Lutjanus analis, L. apodus, L. griseus, L. mahogoni, L. synagris, and O. chrysurus). None comprised >3% of individuals recorded in a bay and most comprised <0.2%. Only two mutton snapper juveniles were recorded, both in a single bay, Turner Hole. The Serranidae were even less abundant; only four species of commercially important Serranidae were recorded, Alphestes afer, Epinephelus fulvus, E. guttatus and E. striatus. None comprised more than 0.3% of individuals in any bay. Although they sampled five habitats in each bay, they sampled habitats proportionally and seagrass made up 60 - 94% of sampled habitat in the three northeastern bays (Mateo and Tobias 2001) and 66 - 85% of sampled habitat in the three southeastern bays (Mateo and Tobias 2004). Less than 4.5 % of their samples were taken in rubble and patch reef habitat in the northeastern bays and 3% in the three southeastern bays. They did not sample the back reef habitat sampled in this study and in Adams and Ebersole's (2002) study. Consistent with this study and Adams and Ebersole (2002), they reported the highest fish density and species density in structured habitats (coral rubble and patch reefs in their study). In Robin Bay, they recorded juveniles of two species of Lutjanidae (L. mahogoni and O. chrysurus) and one species of commercially important Serranidae (Cephalopholis fulvus). L. mahogoni comprised 2% of the total fish recorded, O. chrysurus comprised only 0.4% and C. fulvus comprised 0.1%. The relative fish density of the two lutjanids by size class was reported. Juvenile O. chrysurus 3-5 cm in length had the highest densities in algal plain and rubble. Larger individuals 5-10 cm and >10 cm were more abundant in patch reef habitat. L. mahogoni juveniles 3-5 cm were present in all habitats, but much more abundant in patch reef and rubble habitats. At sizes >5 cm they were uncommon and found only in patch reef habitat. Commercially important lutjanids and serranids made up a minor component of the juvenile fish recorded in six habitats in the embayments surveyed in SE St. Croix by Adams and Ebersole (2002). Five commercially important grouper were recorded only in the large size class (>5 cm) and at percent relative abundance levels ranging from 0 - 0.51% with abundance <0.1% in most of the six habitats surveyed. Five commercially important lutjanids were recorded in all three size classes. Relative abundance was higher ranging from 0 - 11.1% with most less than 0.5%. The species with the highest relative abundance were Ocyurus chrysurus and Lutjanus mahogoni. They were present in all sampled habitats. L. analis was present in four of the six habitats (patch-reef, seagrass, algal plain, and sand) with by far the highest relative abundance in sand (3.85%) compared to the other three habitats (0.06 - 0.32%). All L. analis recorded were large (>5 cm). According to Adams and Ebersole (2002), this size class includes adults. L. analis often roams over sand and seagrass as large juveniles (subadults) and adults. The shallow water habitats of bays on the east end of St. Croix did not appear to contain preferred habitat of commercially important grouper (Serranidae) recruits or juveniles. It also appeared that they are not a major nursery habitat for lutjanids, except possibly the yellowtail snapper (O. chrysurus) and the mahogany snapper (L. mahogoni), which had the highest occurrence in all four studies (Adams and Ebersole 2002; Mateo and Tobias 2001, 2004 and this study). L. analis was uncommon in these studies despite the fact that two of the studies (Mateo
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Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
and Tobias 2001, 2004) carried out most of their fish surveys in seagrass habitat, the presumably preferred habitat for L. analis recruits and juveniles (Anon. 2008). The beachrock on the west end of St. Croix was the only site where actual schools of L. synagris and L. mahogoni were recorded. This habitat appears to be important nursery habitat for these Lutjanus spp. It may be important for others if sampled year round. Nursery habitat for grouper and L. analis was not established. Fishermen (G. Martinez, pers com) reported that larger juvenile L. analis are commonly seen in the seagrass meadows along the southwest shore of St. Croix. Seagrass is dense in this site, but visibility poor owing to the long shore current moving sediment from east to west. This site was briefly searched but no juvenile L. analis were sighted, large or small. It is possible that the paucity of juveniles of L. analis and commercially important serranid species may be a function of the number of recruits available. Although L. analis is now seasonally protected during its peak spawning months and harvest and possession of E. striatus is prohibited, these management measures have only recently been implemented in both territorial and federal waters. The L. analis seasonal closure appears to be working well with no signs of sale of L. analis during the closure period. E. striatus unfortunately is uncommon and when caught is usually hauled from water depths >20 m, resulting in a high release mortality. This likely is slowing its recovery. A spawning aggregation of E. guttatus has been seasonally closed for fishing since 1995, but it is located on Lang Bank in a relatively remote location where enforcement is difficult and mature adults are likely harvested as they migrate to the spawning site. The sizes of red hind in this spawning aggregation have been declining and are considerably smaller than the red hind aggregation in the St. Thomas, Marine Conservation District (Nemeth 2005), which was seasonally closed in 1990 and closed year-round in 1999.
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Chapter 4: Pilot Study of Juvenile Snappers and Groupers in Back Reef Embayments
LITERATURE CITED Adams, A.J. and J.P. Ebersole. 2002. Use of back-reef and lagoon habitats by coral reef fishes. Mar. Ecol. Prog. Ser. 228:213-226. Anon. 2008, SEDAR 15A: Stock Assessment Report 3 (SAR 3), South Atlantic and Gulf of Mexico Mutton Snapper. SAFMC, North Charleston, SC. 410 pp. Bortone, S.A. and J.L. Williams. 1986. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (South Florida): Gray, lane, mutton and yellowtail snappers. U.S. Fish Wildl. Serv. Biol. Rep. 82(11.52). US. Army Corps of Engineers, TR EL-82-4. 25pp. Claro, R. and K.C. Lindeman. 2003. Spawning aggregation sites of snapper and grouper species (Lutjanidae and Serranidae) on the insular shelf of Cuba. Gulf and Carib. Res. 14(2): 91-106. Humman, P. and N. Deloach. 2002. Reef Fish Identification: Florida, Caribbean, Bahamas. New World Publications Inc., Jacksonville, FL. 489 pp. Kendall, M.S., M.E. Monaco, K.R. Buja, J.D. Christensen, C.R. Kruer, M. Finkbeiner, and R.A. Warner. 2001. (On-line). Methods Used to Map the Benthic Habitats of Puerto Rico and the U.S. Virgin Islands. Accessed online 17 Nov 2010. URL: http://biogeo.nos.noaa.gov/projects/mapping/caribbean/startup.htm. Mateo, I. and W.J. Tobias. 2001. Distribution of shallow water coral reef fishes on the Northeast coast of St. Croix, USVI. Caribbean Journal of Science. 37(3-4): 210-226. Mateo, I. and W.J. Tobias. 2004. Survey of nearshore fish communities on tropical backreef lagoons on the southeastern coast of St. Croix. Caribbean Journal of Science. 40(30):327342. Nemeth, R.S. 2005. Population characteristics of a recovering US Virgin Islands red hind spawning aggregation following protection. Mar. Ecol. Prog. Ser. 286:81-97. Accessed online on 30 Nov 2010. URL: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1435719/pdf/nihms2972.pdf Nagelkerken, I., C.M. Roberts, G. van der Velde, M. Dorenbosch, M.C. van Riel, E. Cocheret de la Moriniere, and P.H. Nienhuis. 2002. How important are mangroves and seagrass beds for coral-reef fish? The nursery hypothesis tested on an island scale. Mar. Ecol. Prog. Ser. 244:299-305. Quinn, N.J. 2010. St Croix East End Marine Park: The U.S. Virgin Islands’ First Territorial Marine Park. Proc. 11th International Coral Reef Symp. 1139-1143.
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Quinn, N.J. and B.L. Kojis. 1985. Does the presence of coral reefs in proximity to a tropical estuary affect the estuarine fish assemblage? Proc 5th Int, Coral Reef Cong., Tahiti 5:445-450.
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Recommendations: Mutton Snapper (Lutjanus analis)
RECOMMENDATIONS Future Lutjanus analis (mutton snapper) Research Furture research should concentrate on locating mutton snapper spawning aggregations on the southwest corner of St. Croix. A reef near the red buoy (Nicky's Reef) was the only location where a spawning aggregation of mutton snapper was found and it is an area with the geomorphological characteristics of other mutton snapper spawning sites. This site, or adjacent sites, may be the spawning focal reef(s) for a number of fish species. The site is deeper and more exposed than the site in the Mutton Snapper Seasonal Closed Area (MSSCA) where ripe fish were caught in 2009. The actual location of spawning site should be determined. This could be done by initially by divers conducting searches on Nicky's reef during the peak spawning months of May and June. A more comprehensive research program would include mapping the southwest corner of the St. Croix shelf and then focusing searches on sites with the topography that is characteristic of other spawning sites in the Caribbean. Spawning aggregations may shift location and mapping would provide alternate sites to search during the spawning season. Location of the spawning site could also be done by acoustic tagging of fish. The later technique could also provide information on the movement of mutton snapper during and before/after the spawning season. This could provide information on the migratory pathways to the spawning site and the movement of snapper during the spawning season. The size of L. analis at the onset of reproduction was only broadly determined owing to the small sample size of fish under 440 mm. This small sample size of smaller fish was because we did not catch small fish in April - June when we fished during the spawning season and we were unable to purchase large numbers of small fish in March before the seasonal closure came into effect in April. Spearfishers usually don't target small L. analis, they are too skittish. Trap fishers catch some small L. analis, but not in large numbers. To obtain a more accurate determination of size at the onset of reproduction for each sex, sample size of small fish must increase. It would be best to sample small fish throughout the spawning season (April - June) and pay fishers to make an effort to target small L. analis by paying them either to fish exclusively for small mutton snapper or to pay a considerable bonus for small L. analis to make it worth their while to target them and make the effort to provide them to the researcher. Management Recommendations Considering the association of fish communities with habitat and the apparent decline of scleractinian (hard coral) populations in the MSSCA, management practices that work to preserve coral habitat, such as the ban of bottom tended gear in the federal portion of the MSSCA, should be expanded to the territorial portion of at least the southern half of the MSSCA where spur and groove coral reefs and hillocky reefal habitat dominates. The CFMC should make a formal request to the U.S. Virgin Islands' Government to promulgate compatible regulations in at least the southern portion of the MSSCA.
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Recommendations: Mutton Snapper (Lutjanus analis)
The seasonal prohibition of fishing of Lutjanus analis (mutton snapper) should continue, since the actual location of the aggregation appears to be outside the closed area. It also appears that reproductive fish migrating to the aggregation site within the MSSCA are vulnerable to fishing at least several km from the spawning aggregation site. Fishers stated that they could readily catch mutton snapper outside the Mutton Snapper Seasonal Closed Area by chumming during the spawning season. Fishers mentioned that there were other locations where they thought mutton snapper aggregated to spawn on both the southern and northeastern St. Croix shelf. The seasonal closure protects aggregations of mutton snapper that have not been documented by managers or scientists. The high CPUE and the size distribution of L. analis at fishing sites within the MSSCA indicated that the mutton snapper aggregation a) still exists and b) appears to be reasonably healthy. If, in the future, a quota system is established and St. Croix fishers show a high compliance rate, a quota for mutton snapper during the spawning season, but outside spawning aggregation areas, should be considered. The quota should also be contingent on an adequate enforcement presence. Underwater temperature recorders should be deployed in the MSSCA to record seasonal and annual variation in the subsurface water temperature to understand the relationship between climate change and the spawning period of reef fish.
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Acknowledgements
ACKNOWLEDGEMENTS We gratefully acknowledge funding from the Caribbean Fishery Management Council – NOAA Coral Reef Conservation Grant Program/Projects to Improve or Amend Coral Reef Fishery Management Plans. We also thank Miguel Rolón, Graciela García-Moliner and the CFMC staff for facilitating these efforts. Lutjanus analis were caught during April, May and June within the MSSCA during the closed season under letters of acknowledgement dated April 7, 2009 and April 16, 2010 from the US Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southeast Regional Office and Permit No. STT-014-09 and STT-013-10 from the Government of the Virgin Islands of the United States, Department of Planning and Natural Resources, Division of Fish and Wildlife. After the fish were processed, they were donated to the Herbert Grigg Home for the Aged and the Lighthouse Mission on St. Croix. Of course, we could not have accomplished this work without the competent boat handling, fishing, diving, and marine safety skills of G. Martinez and S. Martinez – Corcino and we appreciate the assistance of Gerson Martinez, Jr. G. Martinez was crucial to the success of this project. He freely provided his considerable knowledge of fish, fish habitats, and fishing garnered from his experience as a trap, line and spearfisher. He has dived all over the St. Croix shelf and has extensive knowledge of the habitats where fish and lobsters are found. He is always learning and gathering information on the behavior, abundance and distribution of fish. We would also like to thank Maximilliano Valasquez for sharing his knowledge of the best fishing spot for mutton snapper in the MSSCA and for pulling in the most mutton snapper. Thanks also to fishers Carlos Farchette and Eddie Schuster, who didn't give up fishing for mutton snapper when seas were high and productivity low in April, 2009. We would like to especially thank Liam Carr for his assistance with fishing, diving searches for mutton snapper, and otolith removal and his diligence in working with others to process otoliths at Texas A&M. Thanks also to Cindy Grace, who assisted on several dives in 2010. We are grateful to Hector Rivera for purchasing fish from fishers for this project in March 2009 and Liam Carr for doing the same in March 2010. We also want to thank the staff of DPNR/Division of Fish and Wildlife for their assistance. Jeremy Blondeau of the University of the Virgin Islands, CMES very kindly provided habitat maps and topographic images based on side scan and multi-beam images of the overall MSSCA from the side scan sonar and multi-beam work done by Side Geophysics GPR International, Inc and Dr. Martha Prada's habitat maps. Blondeau promptly provided coordinates of sample sites upon request for the various habitat types.
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