2009 Drumragh River, Owenreagh South and Tributaries Catchment Status Report
Loughs Agency of the Foyle Carlingford and Irish Lights Commission
Report Ref: LA/CSR/06‐16/10
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Drumragh River, Owenreagh South and Tributaries Catchment Status Report 2009
Report Reference LA/CSR/06‐16/10 Headquarters 22, Victoria Road Londonderry BT47 2AB Northern Ireland Tel: +44(0)28 71 342100 Fax: +44(0)28 71 342720 general@loughs‐agency.org Regional Office Dundalk Street Carlingford Co Louth Republic of Ireland
Picture of hen salmon courtesy of Atlantic Salmon Trust
Written and prepared by: Art Niven Rachel Scott Mairead O’Connor Declan Lawlor & David McCorkill
Tel+353(0)42 938 3888 Fax+353(0)42 938 3888 carlingford@loughs‐ agency.org www.loughs‐agency.org
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Table of Contents 1.0
INTRODUCTION ................................................................................................................ 9
1.1
The Drumragh & Owenreagh South Catchment ....................................................... 11
Fig.1.11 Drumragh River ................................................................................................. 12 Fig 1.12 River Mourne .................................................................................................... 12 Fig 1.13. Drumragh and Owenreagh South catchment topographical map with river network........................................................................................................................... 13 1.2
Atlantic Salmon and Sea Trout .................................................................................. 14
1.3
Non Salmonid Fish Species ........................................................................................ 14
2.0
ATLANTIC SALMON STOCKS ........................................................................................... 15
2.1
Redd Counts .............................................................................................................. 15
Table 2.1 Redd counts for Foyle system, Drumragh & Owenreagh South catchments 2005/06 – 2009/10. *Note 2006/07 had extremely poor water conditions for redd counting .......................................................................................................................... 15 Fig 2.1 Redd counts for Foyle system, Drumragh and Owenreagh South catchments 2005/06 – 2009/10. *Note 2006/07 had extremely poor water conditions for redd counting. * Note Owenreagh redd count is incorporated into Drumragh prior to 2007/08. ......................................................................................................................... 16 Fig 2.11 Redd counts for Foyle system 1952/53 – 2009/10 ........................................... 16 2.2
Juvenile Abundance .................................................................................................. 17
Table 2.2 Loughs Agency semi‐quantitative electrofishing classification system for 0+ salmon and trout ............................................................................................................ 18 Fig 2.21a Drumragh River catchment salmon fry index 2005‐2009, based on mean salmon fry numbers at 33 standard sites surveyed annually......................................... 18 Fig 2.21b Owenreagh River catchment salmon fry index 2001‐2009, based on mean salmon fry numbers at 8 standard sites surveyed annually........................................... 19 Fig 2.22. The mean abundance of salmon fry in 18 catchments in 2009 from semi quantitative electrofishing. *Note above graph is mean for 2009 at all sites surveyed. ........................................................................................................................................ 19 Fig 2.22a Salmon 0+ electrofishing site classification 2009 ........................................... 20 Fig 2.22b Salmon 0+ electrofishing site classification 2009 ........................................... 21 3.0
TROUT STOCKS................................................................................................................ 22 Fig 3.0 Electrofishing survey and trout parr ................................................................... 22
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Fig 3.1a Drumragh River catchment trout fry index 2001‐2009, based on mean salmon fry numbers at 33 standard sites surveyed annually. .................................................... 22 Fig 3.1b Owenreagh River catchment trout fry index 2001‐2009, based on mean salmon fry numbers at 33 standard sites surveyed annually......................................... 23 Fig 3.11. The mean abundance of trout fry in 18 catchments in 2009 from semi quantitative electrofishing. *Note above graph is mean for 2009 at all sites surveyed. ........................................................................................................................................ 23 Fig 3.12a Trout 0+ electrofishing site classification 2009 .............................................. 24 Fig 3.12b Trout 0+ electrofishing site classification 2009 .............................................. 25 Fig 3.13 Salmon and Trout fry distribution 2009............................................................ 26 Fig 3.14 Total salmonid (salmon/trout fry and parr) distribution 2009 ......................... 27 Fig 3.15 Eel presence as recorded during semi quantitative electrofishing surveys 2009. *Note technique used is designed specifically for salmonids. ....................................... 28 Fig 3.16 Lamprey presence as recorded during semi quantitative electrofishing surveys 2009. *Note technique used is designed specifically for salmonids. Further surveys will be required to accurately monitor lamprey populations. .............................................. 29 Fig 3.18 Stickleback presence as recorded during semi quantitative electrofishing surveys 2009. *Note technique used is designed specifically for salmonids. ................ 30 Fig 3.18 Stoneloach presence as recorded during semi quantitative electrofishing surveys 2009. *Note technique used is designed specifically for salmonids. ................ 31 Fig 3.19 Minnow presence as recorded during semi quantitative electrofishing surveys 2009. *Note technique used is designed specifically for salmonids. ............................. 32 4.0
MARINE SURVIVAL .......................................................................................................... 33 Table 4 Marine survival rates for the River Bush of 1SW grilse (after exploitation at sea) pre 1996 and 2002‐2008 smolt cohort. Data supplied by Agri Food and Bioscience Institute, River Bush Salmon Research Station .............................................................. 33 Fig 4 Marine survey areas for salmon in 2008 ............................................................... 34 Fig 4.1 Marine survey areas for salmon in 2009 ............................................................ 35 Fig 4a RV Celtic Explorer SALSEA research cruise........................................................... 36 Figure 4b Picture from the Irish Research Vessel Celtic Explorer taken during the second SALSEA research cruise 16‐24th May 2008 ......................................................... 36 Figure 4c Rotary screw trap in position on the River Faughan directly below the fish pass at Campsie barrage................................................................................................. 37 Table 4.1 Numbers and average weight and length of salmon smolts tagged on the River Faughan 2003‐2009. Coded Wire Tagging equipment was purchased by the
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Loughs Agency in 2005 with funding secured from the European Regional Development Fund through the INTERREG IIIA Programme, administered by the Environment and Heritage Service, on behalf of the Department of Environment. ..... 37 Table 4.12 Recapture data from River Faughan CWT programme. Data for fish tagged in 2008 and recovered in 2009 will not be available until 2010. ................................... 38 Figure 4d Salmon smolt run timing and abundance from rotary screw trap sub sample, River Faughan 2004‐2009. Breaks in data are due to closure of trap during high water conditions. ...................................................................................................................... 38 In 2004 a detailed examination was carried out on the age class of migrating salmon smolts in the Faughan catchment, Table 4.13. .............................................................. 38 Table 4.13 Age class of salmon smolts migrating from the Faughan catchment in 2004 ........................................................................................................................................ 39 Fig 4.14. From top to bottom, Atlantic salmon smolts from the Faughan Catchment, brook lamprey, river lamprey and sea lamprey also caught in the River Faughan smolt trap ................................................................................................................................. 39 5.0
ADULT ABUNDANCE ....................................................................................................... 40
5.1
Recreational Fisheries ............................................................................................... 40
Table 5.1 Declared rod catch returns for salmon and trout in the Foyle and Carlingford areas. Note figures include the Clanrye and Whitewater in the Carlingford area from 2001 onwards. Carcass tagging was introduced in 2001. *Denotes all trout. ............... 40 Table 5.11 Declared catch from the Drumragh catchment for salmon and sea trout 2001‐2009 ....................................................................................................................... 41 Fig 5.1 Angler on the river .............................................................................................. 41 5.2
Commercial Fisheries ................................................................................................ 41
Table 5.1 Salmon rod catch ............................................................................................ 42 Table 5.2 Declared catch from the commercial salmon fisheries 1998‐2009. Note 100% rate of catch returns. * Reduced numbers of commercial nets operating in the Foyle area from 2007 ............................................................................................................... 43 Fig 5.21 Commercial Fishing. Draft netting on the tidal River Foyle and drift netting in Lough Foyle ..................................................................................................................... 43 Fig 5.22 Length weight relationship for combined commercial catches in 2009 .......... 43 5.3
Counters .................................................................................................................... 44
Fig 5.3 New weir constructed on the River Strule in Omagh. Note central fish pass, location for electronic fish counter ................................................................................ 44 Fig 5.31 Fish counting facilities at Sion Mills, River Mourne .......................................... 44
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Table 5.3 River Strule fish counter figures 2007‐2008. *Note 2007 figure is a partial count, also note the River Strule fish counter is a partial counting station. Fish may bypass the counting channel in high water conditions .................................................. 45 Fig 5.32 Monthly fish counts on the Owenkillew River 2004‐2008 ............................... 45 Table 5.31 Sion Mills fish counter figures 2002‐2009. *Note low counts in 2007 and 2008 were influenced by high water levels during peak run timing during June and July. Sion Mills is a partial counter and does not cover the entire length of the weir. In high water levels as experienced in 2007 and 2008 significant numbers of fish can bypass the counting channels. Methods to reduce this are being investigated as part of the Fish Counter Programme Review, commissioned in 2008. ..................................... 46 Fig 5.32 Annual fish counts on the River Mourne 1957‐2009.*Note, variability in type of fish counting equipment over this period .................................................................. 47 5.4
Conservation Limits/Spawning targets ..................................................................... 48
Table 5.4 Upstream of Sion Mills estimated egg deposition 2002‐2009. *Note 2007&2008 figures are a minimum estimate of escapement due to high water levels resulting in the bypassing of the Sion Mills counting channels. .................................... 49 6.0
HABITAT MONITORING................................................................................................... 49 Fig 6.0 Life cycle unit depicting the type of habitat found in spawning, nursery and holding zones .................................................................................................................. 49 Fig 6.01 Examples of spawning, nursery and holding habitats ...................................... 50 Fig 6.02 Drumragh catchment habitat survey map 1 ..................................................... 51 Fig 6.03 Owenreagh catchment habitat survey map ..................................................... 52
7.0
LAND USE ........................................................................................................................ 53 Fig 7.0 Drumragh catchment land use classification ...................................................... 53 Fig 7.01 Drumragh catchment land use classification map............................................ 54
8.0
WATER QUALITY ............................................................................................................. 55 Fig 8.0 Loughs Agency chemical water quality testing in the laboratory....................... 55 Fig 8.01a Drumragh catchment average suspended solids results 2009. Values are in mg/l ................................................................................................................................. 58 Fig 8.01b Owenreagh South catchment average suspended solids results 2009. Values are in mg/l....................................................................................................................... 59 Fig 8.02a Drumragh catchment Ammonia results 2009. Values are in mg/l ................. 60 Fig 8.02b Owenreagh South catchment Ammonia results 2009. Values are in mg/l .... 61 Fig 8.03a Drumragh catchment phosphorous results 2009. Values are in mg/l ............ 62 Fig 8.03b Owenreagh catchment phosphorous results 2009. Values are in mg/l ......... 63 June 1, 2010
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Fig 8.05a Drumragh catchment Biological Monitoring Working Party results 2009 ..... 66 Fig 8.05b Owenreagh South catchment Biological Monitoring Working Party results 2009 ................................................................................................................................ 67 Fig. 8.06: How the different water quality element results are combined to classify ecological status, chemical status and the overall surface water status: Adapted from the ‘Recommendations on Surface Water Classifications Schemes for the purposes of the Water Framework Directive’ UKTAG 2006. ............................................................. 68 Table 8.07. Quality elements which are monitored for the ecological status. .............. 69 Table 8.08. Environmental Quality Ratio classifications for ASPT and NTaxa................ 70 Table 8.09. Environmental Quality Ration Classifications for Diatoms and Macrophytes. ........................................................................................................................................ 70 Table 8.010. Classification for General Chemical & Physiochemical Quality Elements. 71 Table 8.011. Favourable condition targets for Atlantic salmon ..................................... 72 Figure 8.012. Flattened mayfly nymph from the order ephemeroptera high scoring macro invertebrate indicative of good water quality .................................................... 72 Figure 8.013a. Overall WFD surface water status for the Drumragh catchment 2009 . 73 Figure 8.013b. Overall WFD surface water status for the Owenreagh catchment 2009 ........................................................................................................................................ 74 8.1
WFD Fish Classifications 2009 ................................................................................... 75
Figure 8.11. LA fish classification 2009 based on seven sites surveyed within the Foyle and Carlingford areas ..................................................................................................... 75 Figure 8.12. WFD fish surveillance monitoring stations in the Foyle system ................ 76 Figure 8.13. WFD fish classifications in the Foyle system .............................................. 77 Table 8.14 Depletion sampling results from quantitative electrofishing survey Owenreagh South Catchment on the Creevan Burn 2009 ............................................. 78 Table 8.15 Species and numbers caught ........................................................................ 78 Table 8.16 Density of species by age class per 100m2 ................................................... 78 Figure 8.17 Length frequency distribution of juvenile trout .......................................... 79 Figure 8.18 Length weight relationship of juvenile trout ............................................... 79 9.0
CONSERVATION AND PROTECTION ................................................................................ 80 Table 9.0. Breakdown of conservation and protection duties in the Drumragh catchment 2002‐2009. *No data provided for 2009...................................................... 80 Table 9.01 Seized nets, salmon, rod/reels and vehicles in the Foyle system 2003‐2009 ........................................................................................................................................ 80
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Table 9.02 Seizures in the Drumragh (Owenreagh South in brackets) catchment 2006‐ 2009 ................................................................................................................................ 80 9.1
Habitat Improvement Works .................................................................................... 81
Fig 9.1. Examples of in‐stream habitat improvements on the Seskinore River and Fintona River ................................................................................................................... 85 10.0 ENVIRONMENTAL ISSUES ............................................................................................. 85 11.0 DESIGNATED AREAS ...................................................................................................... 86 12.0 GENETIC STUDY ............................................................................................................. 87 13.0 POLLUTION MONITORING ............................................................................................ 87 14.0 FISHERY OFFICERS DRUMRAGH AREA REPORT 2009 ................................................... 87 15.1
Foyle and Carlingford Areas Ongoing Actions for 2010 ........................................ 88
15.0 ACTIONS FOR 2010 ....................................................................................................... 90 15.2 Drumragh and Owenreagh South Catchments Potential Habitat Improvement Schemes for 2010 ................................................................................................................ 90 15.3
Owenkillew Catchment Specific Actions for 2010................................................. 90
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Drumragh River, Owenreagh South and Tributaries Catchment Status Report 2009 1.0
INTRODUCTION
Welcome to the 2009 Loughs Agency Catchment Status Report series. The reports have been updated in 2010 to include survey data collected during 2009. Environmental issues of relevance to the water quality and fisheries resources of the Foyle and Carlingford areas are discussed and intervention outlined. This is one of an annual series of catchment status reports produced by the Loughs Agency. The primary objective of the catchment status reports is to disseminate catchment specific information to all interested stakeholders. The reports continue to be consulted widely by a variety of stakeholders including local angling associations, fishery owners, statutory bodies, environmental consultants, students, conservation Non Governmental Organisations and private individuals. The catchment status reports provide summary data which demonstrates the work that the Loughs Agency conducts within specific catchments and outlines catchment specific objectives. The theme for the 2009 catchment status reports is water quality. The first River Basin Management Plans, a requirement under the European Union Water Framework Directive (2000/60/EC) were published in December 2009. These reports are written for each river basin district by the competent authorities in both Northern Ireland and the Republic of Ireland. Some of the river basin districts are classified as International River Basin Districts and within these areas there is cooperation in managing shared waters. The Water Framework Directive (WFD) requires the assessment of aquatic ecological status. Ecological status has been and will continue to be monitored using new monitoring programmes and classification systems developed for the Water Framework Directive. Initial results and more details on the parameters measured are provided within this report. The Loughs Agency has been conducting freshwater fish monitoring for inclusion within overall surface water classifications in both Northern Ireland and the Republic of Ireland and is well positioned to facilitate and participate in the implementation of programmes of measures designed to improve water quality on a cross border basis. Water bodies will continue to be monitored within each six year reporting cycle for river basin planning with reporting due next in 2015, 2021 and 2027. The overall objective is to have all water bodies reaching good ecological status. The River Basin Management Plans are intended to provide the primary means of coordinating June 1, 2010
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and integrating the management and protection of the aquatic environment. Working in partnership has been highlighted within the directive as an essential mechanism for full implementation and delivery. The Loughs Agency is playing an active role within this process and would encourage all stakeholders to participate fully. Programmes of measures to deliver the key objective of attaining good ecological status within all water bodies have been developed and will need to be further refined with active participation from statutory and non statutory bodies. Local Management Areas (LMA’s) have been defined by the Northern Ireland Environment Agency (NIEA) with information leaflets produced which includes details of specific local measures identified to improve the aquatic environment within these areas. Continued consultation and partnership working will be required to maximise the potential of these and to develop them into feasible action plans. The Loughs Agency views the contribution of the catchment status reports as vital to informing planned action for improving the local aquatic environments of the Foyle and Carlingford areas. Loughs Agency members of staff also play an active part in Water Framework Directive implementation through active participation within the Catchment Stakeholder Groups, Northern Ireland Water Framework Directive Fish Group and other Water Framework Directive working groups.
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1.1
The Drumragh & Owenreagh South Catchment
The Drumragh River is made up of a series of branching river systems which extend along the southern end of the Loughs Agency Foyle catchment. Its upper tributaries include the Seskinore River, Routing Burn and Quiggery River which wind among drumlins (glacial deposits) to the south. The town of Omagh is sited at the confluence of the Drumragh and Camowen rivers where it forms the River Strule. The Owenreagh River runs west upstream from the confluence of the Drumragh River with the Quiggery River. The Drumragh and Owenreagh South catchments have been significantly impacted by past large scale arterial drainage schemes which have impacted on the quality of in-channel habitat diversity. Drumlins are the dominant influence on land form within the Drumragh Catchment, with sandstone ridges to the east of Fintona and uplands of west Tyrone forming a distant backdrop. The drumlins are packed quite densely to form a deep undulating lowland landscape with a distinctive character. Narrow river valleys dominate the landscape with minor tributaries winding around the small hills. There are also patches of marsh in low-lying areas. The drumlins are predominantly pasture but have a diverse small-scale landscape pattern. The land-use in the Drumragh and Owenreagh catchment is primarily agricultural with smallholdings predominant in the upper reaches and more intensive farming in the lower valleys. The Drumragh River has a main channel length of approximately 51km and has a catchment area of 154km2. The Drumragh and Owenreagh South catchment is impacted upon by a wide range of anthropogenic factors within both the terrestrial and aquatic environments. A diverse array of impacts include amongst others; agriculture, sand and gravel extraction, commercial forestry, commercial and recreational fishing, industry, water abstraction, sewage treatment, diffuse and point source pollution, invasive plant species, urban sprawl and flood defences. Increasing pressures on the aquatic environment within the Drumragh and Owenreagh catchment requires appropriate monitoring, control and remediation if native biodiversity is to be preserved. The proximity of the Drumragh catchment to an urban area and the surrounding land-use exacerbates many of these issues. As the competent authority for fishery issues within the catchment the Loughs Agency are required to fulfil a variety of national and international obligations. European Directives including the Habitats Directive and Water Framework Directive and the transposing national legislation have assisted in creating a legislative framework in which to drive forward sustainable management of riparian and aquatic habitats and the native species which inhabit them.
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Fig.1.11 Drumragh River
Fig 1.12 River Mourne
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Fig 1.13. Drumragh and Owenreagh South catchment topographical map with river network.
1.2
Atlantic Salmon and Sea Trout
Salmon and Sea Trout are referred to as being anadromous meaning that they migrate between the freshwater and marine environments returning to freshwater to reproduce. This complex life history exposes them to varied environmental pressures and recreational and commercial fisheries. Adult Atlantic salmon return to their natal rivers where spawning takes place. Sea trout also demonstrate an ability to return to their natal river but their homing instinct may not be as strong as those of the Atlantic salmon. After the eggs hatch the juveniles (initially referred to as fry and then parr) remain in freshwater for up to three years. Smoltification is the physiological adaptation which occurs when the juvenile salmon change from the parr stage (freshwater phase) to the smolt stage (marine phase). In the Foyle system this can occur after one, two or three years. Most Foyle salmon (referred to as post smolts) will remain after smoltification in the North Atlantic for one year and are referred to on their return to the coast and rivers as grilse. Salmon which stay at sea for longer than one year are referred to as multi sea winter (MSW) salmon. 1.3
Non Salmonid Fish Species
As highlighted earlier populations of other non salmonid fish species occur within the Strule catchment. In the past monitoring was targeted at salmonid species however with obligations under the Water Framework Directive other non salmonid fish species are being monitored more closely. Fish species presence and abundance can act as a good environmental/ecological indicator demonstrating the ability of the aquatic habitat to support a diverse array of native species. Populations of the European Eel, Stickleback, River/Brook and Sea Lamprey form an important part of the native fisheries biodiversity of the Drumragh and Owenreagh South catchments. Maintaining high standards of water quality and appropriate habitat for these species is essential for the overall health of the aquatic ecosystem.
Fig 1.3 Sample of fish from the Foyle estuary
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
2.0
ATLANTIC SALMON STOCKS
In order to describe the status of salmon stocks each of the following points need to be considered: • • • • • 2.1
Redd Counts Juvenile abundance Marine survival Adult abundance Exploitation
Redd Counts
Redds are spawning nests created by salmon or trout. Differentiation between salmon and trout redds can be made as salmon redds tend to be larger in size and trout tend to spawn earlier than salmon within the Foyle system. Research within the Foyle system using extensive annual redd count data has highlighted a good relationship between the number of redds and the total annual catch of salmon. Table 2.1 shows redd count data for the Drumragh and Owenreagh catchment. Water flow is of significance when monitoring redds as in high water conditions the ability to see and count redds in rivers is impaired. Figure 2.11 outlines redd counts within the Foyle area and the Drumragh catchment. Year
2005/06
2006/07
2007/08
2008/09
2009/10
Foyle System
5354
*1338
3039
5507
4000
Drumragh Catchment
519
*252
238
329
210
Owenreagh Catchment
Included in Drumragh
*Included in Drumragh
96
266
108
Drumragh as a % of Foyle
10
*19
8
7
5
Included in Drumragh
*Included in Drumragh
3
5
3
Owenreagh as a % of Foyle
Table 2.1 Redd counts for Foyle system, Drumragh & Owenreagh South catchments 2005/06 – 2009/10. *Note 2006/07 had extremely poor water conditions for redd counting
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Drumragh & Owenreagh Redd Count 6000
5507
5354 Total Foyle
Number of Redds
5000
Drumragh Catchment 4000
Owenreagh Catchment
4000
3039 3000
2000 1338 1000
519
252
238
2006/7
2007/8
96
392 266
210 108
0 2005/6
2008/9
2009/10
Year Fig 2.1 Redd counts for Foyle system, Drumragh and Owenreagh South catchments 2005/06 – 2009/10. *Note 2006/07 had extremely poor water conditions for redd counting. * Note Owenreagh redd count is incorporated into Drumragh prior to 2007/08.
Foyle Area Redd Count 1952/53‐2009/10 25000
Number of Redds
20000
15000
10000
5000
1952 1954 1956 1958 1960 1962 1964 1966 1968 1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002/3 2004/5 2006/7 2008/9
0
Year Fig 2.11 Redd counts for Foyle system 1952/53 – 2009/10
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
2.2
Juvenile Abundance
Within the Loughs Agency jurisdiction trends in abundance of juvenile salmonids are monitored by annual semi-quantitative electrofishing surveys. The numbers, age and species of fish captured during five minute timed electrofishing surveys are compared with previous year’s data allowing for change to be monitored, facilitating suitable fishery management practices to be implemented. In 2009 a total of 485 sites were semi-quantitatively electrofished within the Foyle system. The results for each site for salmon and trout are classified as excellent (>25 fish), good (15-24 fish), fair (5-15 fish), poor (1-4 fish) and absent (0 fish), Table 2.2. Figures 2.21 - 2.22 outline the salmon 0+ electrofishing results and site classifications for the Drumragh & Owenreagh catchments in 2009. Please consult previous status reports for site classifications in other years. Semi-quantitative electrofishing was developed to monitor 0+ salmonids (fry/young of the year). In order to quantify the abundance of 1+ salmonids (parr and older) fully quantitative electrofishing surveys are required which can be used to calculate fish densities within a defined area. Rivers and tributaries with good environmental quality are more likely to support good populations of each year class. Fish populations can vary considerably over time and location, it is therefore necessary to monitor the populations over a period of years to highlight meaningful trends before considering remedial activities such as habitat improvement works. These trends are being continually monitored by the Loughs Agency and the most appropriate management options considered. There are a variety of reasons why electrofishing sites may be perceived to be under producing, these can include, lack of suitable juvenile habitat, the presence of impassable obstacles to migratory fish species on lower sections of a tributary, pollution, inconsiderate channel maintenance, tunnelling by bank side vegetation, stream gradient and poor forestry practices etc. The critical point is to recognise the major factors at play and to investigate all possible reasons for underproduction accepting that there may be inherent reasons as to why production may not be improved upon in certain areas. When the same areas are surveyed for other non salmonid species it may be discovered that they provide habitat more suited to these species. Habitat improvement works and the rationale behind them are discussed in greater detail later. Obligations under the Water Framework Directive are driving quantitative surveys of both salmonid and non salmonid species under proposed Surveillance, Operational, Investigative and Protected Area monitoring programmes.
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Symbol
Grade
Number of 0+ Salmonids
Excellent
>25
Good
15-24
Fair
5-14
Poor
1-4
Absent
0
Table 2.2 Loughs Agency semi-quantitative electrofishing classification system for 0+ salmon and trout
Drumragh Average Salmon Fry (2005‐2009) 10
9
9
Salmon 0+
Average Fry/ 5 Minute Fishing
9 8 7 6 5
4
4
4
2008
2009
4 3 2 1 0 2005
2006
2007 Year
Fig 2.21a Drumragh River catchment salmon fry index 2005-2009, based on mean salmon fry numbers at 33 standard sites surveyed annually
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Owenreagh South Average Salmon Fry (2005‐ 2009) 7 Salmon 0+
Average Fry/5 Minute Fishing
6 6 5 4
4
4 3 2 2 1 1 0 2005
2006
2007
2008
2009
Year Fig 2.21b Owenreagh River catchment salmon fry index 2001-2009, based on mean salmon fry numbers at 8 standard sites surveyed annually
86
37
6
5
5
5
4
4
3
1
0
Foyle South
Fairywater
Glenmornan
Finn
Mourne
Derg
Burn Dennet
Roe
Owenkillew
Faughan
9
Owenreagh S
19
Drumagh
22
Camowen
23
Culdaff
39
Strule
40
Deele
43
Glenelly
100 90 80 70 60 50 40 30 20 10 0
Owenreagh East
Average Salmon Fry/5 Minute
Summary of Salmon Fry Semi Quantitative Electrofishing Results 2009
Catchment
Fig 2.22. The mean abundance of salmon fry in 18 catchments in 2009 from semi quantitative electrofishing. *Note above graph is mean for 2009 at all sites surveyed. June 1, 2010
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Fig 2.22a Salmon 0+ electrofishing site classification 2009
Fig 2.22b Salmon 0+ electrofishing site classification 2009
3.0
TROUT STOCKS
Annual trends in the populations of juvenile trout are also monitored within the Loughs Agency jurisdiction using the same methodology and classification system as those employed for salmon. The semi quantitative electrofishing results for trout fry in the Drumragh & Owenreagh South catchments and site classifications are displayed in Figs 3.1, 3.11 & 3.12.
Fig 3.0 Electrofishing survey and trout parr
Drumragh Average Trout Fry (2005‐2009) 4.5 Trout 0+
4
Average Fry/ 5 Minute Fishing
4 3.5 3 3 2.5 2
2
2 1.5 1 1 0.5 0 2005
2006
2007
2008
2009
Year
Fig 3.1a Drumragh River catchment trout fry index 2001-2009, based on mean salmon fry numbers at 33 standard sites surveyed annually.
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Owenreagh South Average Trout Fry (2005‐ 2009) 6 Trout 0+
Average Fry/5 Minute Fishing
5 5 4 3 3 2
2
2
2007
2008
2009
2 1 0 2005
2006
Year Fig 3.1b Owenreagh River catchment trout fry index 2001-2009, based on mean salmon fry numbers at 33 standard sites surveyed annually.
5
4
4
4
3
3
3
3
3
2
Finn
Camowen
Drumagh
Glenelly
Owenkillew
Derg
Deele
Fairywater
Owenreagh S
6
Strule
6
Mourne
7
Owenreagh East
9
Burn Dennet
10
Faughan
13
Roe
14
Culdaff
45
Glenmornan
50 45 40 35 30 25 20 15 10 5 0
Foyle South
Average Trout Fry/5 Minute Fishing
Summary of Trout Fry Semi Quantitative Electrofishing Results 2009
Catchment
Fig 3.11. The mean abundance of trout fry in 18 catchments in 2009 from semi quantitative electrofishing. *Note above graph is mean for 2009 at all sites surveyed.
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Fig 3.12a Trout 0+ electrofishing site classification 2009
Fig 3.12b Trout 0+ electrofishing site classification 2009
Fig 3.13 Salmon and Trout fry distribution 2009
Fig 3.14 Total salmonid (salmon/trout fry and parr) distribution 2009
Fig 3.15 Eel presence as recorded during semi quantitative electrofishing surveys 2009. *Note technique used is designed specifically for salmonids.
Fig 3.16 Lamprey presence as recorded during semi quantitative electrofishing surveys 2009. *Note technique used is designed specifically for salmonids. Further surveys will be required to accurately monitor lamprey populations.
Fig 3.18 Stickleback presence as recorded during semi quantitative electrofishing surveys 2009. *Note technique used is designed specifically for salmonids.
Fig 3.18 Stoneloach presence as recorded during semi quantitative electrofishing surveys 2009. *Note technique used is designed specifically for salmonids.
Fig 3.19 Minnow presence as recorded during semi quantitative electrofishing surveys 2009. *Note technique used is designed specifically for salmonids.
4.0
MARINE SURVIVAL
The numbers of salmon that survive to return to the freshwater environment are greatly influenced by conditions in the marine environment. Climate change leading to changes in sea surface temperatures, prey abundance, high seas fishing, marine pollution, sub lethal levels of pollution and predation all have an effect on the Atlantic salmon and indeed other migratory fish species chances of survival. Marine survival trends are monitored on a number of index rivers in the North East Atlantic where total trapping facilities are available for both migrating juvenile and adult populations. Total trapping allows for an accurate count of all migrant smolts (total freshwater production) and returning adults to be made and therefore an accurate estimate of marine survival. These projects are facilitated by the use of Coded Wire Tags (CWT). Coded wire tags are small (2-3mm long) micro tags that are injected automatically by a CWT device into the snout cartilage of anaesthetised fish remaining there for the duration of the life of the fish. CWT fish also have their adipose fin (small fin between the dorsal fin and caudal fin (tail fin)) removed so that they can be identified in the various fisheries that may intercept them. In Ireland a comprehensive screening programme is conducted at all major landing ports and markets. This programme is important in monitoring the effect of the remaining salmon fisheries on salmon stocks from rivers both within and outside of the island of Ireland. Trends in marine survival for the River Bush (nearest index river to the Foyle system) confirm patterns observed elsewhere on the southern stocks of North Eastern Atlantic salmon, which indicate that marine survival can be variable between stocks and years. In the River Bush marine survival has decreased considerably over recent years as outlined in Table 4. Year of Smolt Cohort
Year of Returning 1SW Grilse
Marine Survival %
Pre 1996
Pre 1998
Circa 30%
2002
2003
5.9
2003
2004
4.3
2004
2005
4.6
2005
2006
4.2
2006
2007
13.0
2007
2008
7.5
2008
2009
3.3
Table 4 Marine survival rates for the River Bush of 1SW grilse (after exploitation at sea) pre 1996 and 2002-2008 smolt cohort. Data supplied by Agri Food and Bioscience Institute, River Bush Salmon Research Station
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
The figures outlined in table 4 are mirrored by those for other index rivers monitoring the southern stocks of North Eastern Atlantic salmon populations. These figures suggest that salmon are facing increased pressure for survival at sea. A major new international research project called SALSEA - Merge has been developed by scientists from the North Atlantic Salmon Conservation Organisation (NASCO) parties and its research wing the International Atlantic Salmon Research Board (IASRB). There are twenty consortium members in total including the Loughs Agency. SALSEA aims to monitor how Atlantic salmon use the ocean; where they go; how they use ocean currents, and the ocean’s food resources, and what factors influence migration and distribution at sea. Research cruises commenced in 2008 and continued in 2009 to collect the necessary data to answer the questions listed above. In 2008 426 post smolts were caught by the two Irish cruises and 363 post smolts caught by the Faroese in the areas highlighted below. In 2009 464 post smolts were captured during the two Irish Research cruises which concentrated on the continental shelf edge to the north west of Ireland and on the North Norwegian sea. Further information and project details can be found at: http://www.nasco.int/sas/salsea.htm
Fig 4 Marine survey areas for salmon in 2008 June 1, 2010
34
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Fig 4.1 Marine survey areas for salmon in 2009
June 1, 2010
35
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Fig 4a RV Celtic Explorer SALSEA research cruise
Figure 4b Picture from the Irish Research Vessel Celtic Explorer taken during the second SALSEA research cruise 16-24th May 2008
June 1, 2010
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Since 2003 partial smolt trapping including CWT tagging has been conducted in the Faughan catchment using a rotary screw trap, Fig 4c.
Figure 4c Rotary screw trap in position on the River Faughan directly below the fish pass at Campsie barrage.
Smolt trapping can have a number of objectives including the monitoring of both salmonid and non salmonid species. Sampling of the age composition, obtaining information on run timing and recording length/weight data is conducted in tandem with the tagging programme. As mentioned above total counts of migrating smolts can be made on rivers. Where this is unfeasible due to the absence of total trapping facilities, total smolt migration can be estimated by means of a mark-recapture experiment. In 2004 an estimate of total smolt production for the Faughan catchment was made by a mark-recapture study resulting in a minimum run size estimate of 33,854 migrating salmon smolts. The estimate was a minimum due to a number of high water events that prevented the smolt trap from fishing for a period of time during the peak smolt migration period. Tables 4.1 and 4.12 outline numbers of salmon smolts tagged from 2003-2008 and recapture data for 2003 and 2004. Year 2003 2004 2005 2006 2007 2008 2009
No of Salmon Smolts Tagged 2113 2500 2210 1025 2062 1865 561
Average Length (mm) 149 134 133 133 135 130 134
Average Weight (g) 33.45 24.6 23.6 25.36 27.1 22.1 24.4
Table 4.1 Numbers and average weight and length of salmon smolts tagged on the River Faughan 2003-2009. Coded Wire Tagging equipment was purchased by the Loughs Agency in 2005 with funding secured from the European Regional Development Fund through the INTERREG IIIA Programme, administered by the Environment and Heritage Service, on behalf of the Department of Environment.
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Year Tagged
Year Recaptured
Numbers Recaptured
Recapture Location
2003
2004
12
2004
2005
16
2005
2006
3
Greencastle, Burtonport, Malin Head, Belmullet and Torr Head Greencastle, Malin Head, Donegal and Galway Bay Greencastle
2006
2007
2
Greencastle and Ballycastle
2007
2008
2
Greencastle
Table 4.12 Recapture data from River Faughan CWT programme. Data for fish tagged in 2008 and recovered in 2009 will not be available until 2010.
River Faughan Salmon Smolt Run Timing and Abundance 2004 ‐ 2009 2004 600
2005
Number of Salmon Smolts Trapped
2006 500 2007 2008
400
2009 300
200
100
23‐May
21‐May
19‐May
17‐May
15‐May
13‐May
11‐May
09‐May
07‐May
05‐May
03‐May
29‐Apr
01‐May
27‐Apr
25‐Apr
23‐Apr
21‐Apr
19‐Apr
17‐Apr
15‐Apr
13‐Apr
11‐Apr
09‐Apr
07‐Apr
05‐Apr
03‐Apr
0
Date Figure 4d Salmon smolt run timing and abundance from rotary screw trap sub sample, River Faughan 2004-2009. Breaks in data are due to closure of trap during high water conditions. In 2004 a detailed examination was carried out on the age class of migrating salmon smolts in the Faughan catchment, Table 4.13. June 1, 2010
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Age at Smolting 1 2 3
% 13 83 4
Table 4.13 Age class of salmon smolts migrating from the Faughan catchment in 2004
Fig 4.14. From top to bottom, Atlantic salmon smolts from the Faughan Catchment, brook lamprey, river lamprey and sea lamprey also caught in the River Faughan smolt trap
June 1, 2010
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
5.0
ADULT ABUNDANCE
Adult Atlantic salmon abundance is assessed in three ways: directly by using commercial netting/recreational rod catches and fish counters and indirectly by reference to conservation limits/spawning targets. Using catch data as a measure of population status is a well established and extensively used technique. In the Foyle system annual commercial and recreational catch data has been recorded since the establishment of the Foyle Fisheries Commission in 1952, with some data available before this period. The relationship between catch and stock is complex and care should be applied in interpretation. A more precise measure of catch incorporates fishing effort (number of licences issued or the amount of time fished) and is referred to as catch per unit effort (CPUE). 5.1
Recreational Fisheries
One problem encountered when analysing catch data is unreported catch. All recreational fishers are required by law to make catch returns. This information facilitates management decision making and therefore it is vitally important that all catch returns are accurate and made promptly at the season’s end. Year
Declared Rod Catch Salmon
Declared Rod Catch Sea Trout
Returns as a % of Licences Issued
1999
1022
679
3.74
2000
723
417
2.55
2001
3188
450
17.68
2002
5117
1010
27.93
2003
1844
361
15.5
2004
2285
75
13.99
2005
4084
413
25.77
2006
3476
469
37
2007
4929
379
22.11
2008
4060
815
54.94
2009
2923
*550
43.88
Table 5.1 Declared rod catch returns for salmon and trout in the Foyle and Carlingford areas. Note figures include the Clanrye and Whitewater in the Carlingford area from 2001 onwards. Carcass tagging was introduced in 2001. *Denotes all trout.
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Year
Declared Catch Drumragh Catchment Salmon 17 25 16 16 84 26 54 103 49
2001 2002 2003 2004 2005 2006 2007 2008 2009
Declared Catch Drumragh Catchment Sea Trout 0 0 0 0 14 5 13 33 46
Table 5.11 Declared catch from the Drumragh catchment for salmon and sea trout 2001-2009
Fig 5.1 Angler on the river
5.2
Commercial Fisheries
Commercial fisheries have traditionally operated within the Foyle sea area, Lough Foyle and tidal River Foyle. The drift net and draft net fisheries as well as the rod fisheries have been closely regulated with a real time management regime in place to monitor the numbers of fish migrating up key rivers. If predetermined numbers of fish have not been counted by the strategically placed electronic fish counters at Sion Mills weir (River Mourne), Campsie Barrage (River Faughan) and the Plumb Hole (River Roe) then specified closures of the commercial and/or recreational fisheries are enforced. In 2007 new regulations were introduced to reduce the number of commercial nets operating within the Foyle area and all mixed stock interceptory drift nets seaward of Lough Foyle were curtailed. This decision was made to comply with the EU Habitats Directive, similar curtailment of mixed stock fisheries were introduced in the Republic of Ireland. Within the Foyle area this was achieved through a voluntary hardship scheme. 18 out of 112 drift nets remain in Lough Foyle, those remaining have been reduced in size from 900m to 500m and 10 out of 50 draft nets remain. This represents a significant reduction of netting effort. Regulations were also introduced to limit the numbers of fish which could be retained by the recreational rod fishery throughout the Foyle and Carlingford areas. June 1, 2010
41
Salmon Rod Catch 1952 ‐ 2009 18000 Reported Rod Catch 16000 Corrected Rod Catch 14000
Number of Salmon
12000 10000 8000 6000 4000 2000
Year
Table 5.1 Salmon rod catch
2008
2006
2004
2002
2000
1998
1996
1994
1992
1990
1988
1986
1984
1982
1980
1978
1976
1974
1972
1970
1968
1966
1964
1962
1960
1958
1956
1954
1952
0
Year
Drift Catch
Draft Catch
Total Drift and Draft
1998
31296
11141
42437
1999 2000 2001
15397 22333 13500
7893 10339 9476
23290 32672 22976
2002
28851
11917
40768
2003 2004 2005
15741 12800 13391
16991 9490 12143
32732 22290 25534
2006 *2007 2008
6160 2598 1248
6031 2774 2924
12191 5372 4172
2009
611
1326
1937
Table 5.2 Declared catch from the commercial salmon fisheries 1998-2009. Note 100% rate of catch returns. * Reduced numbers of commercial nets operating in the Foyle area from 2007
Fig 5.21 Commercial Fishing. Draft netting on the tidal River Foyle and drift netting in Lough Foyle
Length Weight Relationship for Combined Commercial Catches 2009 (N=581) 10.00 y = 0.0022x2 ‐ 0.1587x + 3.8724 R² = 0.894
Weight (Kg)
8.00 6.00 4.00 2.00 0.00 0
10
20
30
40
50
60
70
Length (cm)
Fig 5.22 Length weight relationship for combined commercial catches in 2009
80
90
100
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5.3
Counters
Within the Foyle system a number of river catchments have electronic fish counting facilities that provide estimates on the run timing and abundance of fish >45cm. A new weir incorporating fish counting facilities has been constructed on the River Strule downstream of the confluence with the Camowen River in Omagh. Commissioned in 2007 the River Strule fish counter will provide a partial count of fish ascending the upper Strule before continuing their migration into the rivers of the Drumragh, Camowen and Owenreagh catchments. The upper Strule counter became operational in September 2007 recording 126 fish > 45cm to the end of the year. The counting channel forms part of the weir but in high water events fish can pass over the weir undetected. A time series of counts for the River Strule fish counter in Omagh and the Sion Mills fish counting station on the River Mourne downstream are outlined in tables 5.32 and 5.33.
Fig 5.3 New weir constructed on the River Strule in Omagh. Note central fish pass, location for electronic fish counter
Fig 5.31 Fish counting facilities at Sion Mills, River Mourne June 1, 2010
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Year
Number of fish >45cm
2007
126
2008
207
2009
252
Table 5.3 River Strule fish counter figures 2007-2008. *Note 2007 figure is a partial count, also note the River Strule fish counter is a partial counting station. Fish may bypass the counting channel in high water conditions
River Strule Fish Counter Figures 2007 ‐ 2009 90 2007 80 2008 70 2009 Number of Fish > 45cm
60
50
40
30
20
10
0 JAN
FEB
MAR
APR
MAY
JUN
JULY
AUG
SEPT
OCT
NOV
DEC
Month
Fig 5.32 Monthly fish counts on the Owenkillew River 2004-2008
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Year
Number of fish >45cm
2002
12991
2003
12129
2004
10270
2005
9397
2006
9926
*2007
*3714
*2008
*3452
2009
8410
Table 5.31 Sion Mills fish counter figures 2002-2009. *Note low counts in 2007 and 2008 were influenced by high water levels during peak run timing during June and July. Sion Mills is a partial counter and does not cover the entire length of the weir. In high water levels as experienced in 2007 and 2008 significant numbers of fish can bypass the counting channels. Methods to reduce this are being investigated as part of the Fish Counter Programme Review, commissioned in 2008.
River Mourne Fish Counter Figures 2004 ‐2009 4500 2004
4000
Number of fish >45cm
2005 3500
2006
3000
2007 2008
2500
2009
2000 1500 1000 500 0
DEC
NOV
OCT
SEPT
AUG
JULY
JUN
MAY
APR
MAR
FEB
JAN
‐500
Month Fig 5.33 Monthly fish counts on the River Mourne 2004-2008 as recorded at Sion Mills
June 1, 2010
46
*1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 *1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
Number of Fish > 45cm
River Mourne Electronic Fish Counters Figures 1957‐2009
25000
20000
15000
10000
5000
0
Year
Fig 5.32 Annual fish counts on the River Mourne 1957-2009.*Note, variability in type of fish counting equipment over this period
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
5.4
Conservation Limits/Spawning targets
Another way to assess adult salmon stock status is to monitor run sizes on rivers and to compare them with predefined reference points called conservation limits. In the Foyle system the conservation limits define a level of spawning that optimises the sustainable catch by commercial and recreational fisheries. If exploitation rates increase above the sustainable catch levels the catch may increase in the short-term but the stock will eventually reduce. Conservation limits demarcate the undesirable spawning stock level at which recruitment would begin to decline significantly (NASCO). The real time management regime incorporating the setting of management targets and spawning targets implemented in the Foyle aims to manage the fisheries and spawning populations in a sustainable manner. The management and spawning targets are set for the various river catchments based on the amount and quality of nursery habitat present. River habitat surveys are carried out along each stretch of river and graded according to the type and quality. Egg deposition levels are set according to the quality grading of each section of nursery habitat. There are four grades of nursery habitat, however for the purpose of setting egg deposition levels only grades 1-3 are utilised. Grade 1 denotes the best quality habitat. The egg deposition rate/carrying capacity is set as follows. Grade 1 = 10 eggs per m², grade 2 = 5 eggs per m² and grade 3 = 2.5 eggs per m². The total number of eggs is calculated by multiplying the area of each grade of nursery habitat by the appropriate density of eggs per m². 25% is deducted from the management target allowing for loss of salmon by angling (15%) and poaching and predation (10%). The remaining figure is referred to as the conservation limit/spawning target. Once the number of eggs required for each river has been established this can be converted to a total number of fish required to achieve the management targets and conservation limit/spawning targets. The average fecundity (number of eggs produced per female) of Foyle salmon has been estimated at 2500 and the ratio of female to male salmon estimated at 60:40. When combined with the amount of nursery habitat of the various grades this equates to the conservation limit/spawning target. A management target of 8000 adult Atlantic salmon has been set for above Sion Mills, this equates to a conservation limit/spawning target of over 6000 salmon or 9,000,000 eggs.
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Year
No of Fish Across Counter
Estimated Egg Deposition
2002
12991
14,614,875
2003
12129
13,645,125
2004
10270
11,553,750
2005
9397
10,571,625
2006
9926
11,166,750
*2007
*3714
*4,178,250
*2008
*3452
*3,883,500
2009
8410
9,461,250
Table 5.4 Upstream of Sion Mills estimated egg deposition 2002-2009. *Note 2007&2008 figures are a minimum estimate of escapement due to high water levels resulting in the bypassing of the Sion Mills counting channels.
6.0
HABITAT MONITORING
The Loughs Agency has carried out extensive habitat surveys on all the major rivers and tributaries within the Foyle and Carlingford catchments. Habitat surveys are carried out on foot. Although time consuming this is at present the best method for classifying the various grades of habitat. Habitat is classified into one of three life cycle units Fig 6.0, the presence and order of which is essential to the productive capacity of a salmonid river. Other non salmonid species also benefit from diverse in-channel habitat. The life cycle unit categories include spawning, nursery and holding habitat. Each category is then graded on a scale of 1-4, 1 representing the best quality attainable and 4 the worst. Other data collected during these surveys include channel width and impassable barriers to migratory fish species.
Fig 6.0 Life cycle unit depicting the type of habitat found in spawning, nursery and holding zones
June 1, 2010
49
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Fig 6.01 Examples of spawning, nursery and holding habitats
June 1, 2010
50
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Fig 6.02 Drumragh catchment habitat survey map 1 June 1, 2010
51
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Fig 6.03 Owenreagh catchment habitat survey map June 1, 2010
52
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
7.0
LAND USE
Land use classification is an important tool when assessing the potential impacts within a particular river catchment or indeed when looking at specific land use and land management practices. Land use impacts could have either a positive or negative impact on rivers and tributaries. A good understanding of the land use within a catchment is therefore imperative in managing at a catchment scale. Land use in Northern Ireland has been captured using satellite imaging technology and classified to type. The following figures outline the broad land use classification within the Drumragh Catchment.
Land Use in the Drumragh Catchment Discontinuous Urban 4%
9%
1% Pastures
1%
Agriculture/Natural Vegetation
2%
Coniferous Forests 83%
Natural Grassland Peatbogs
Fig 7.0 Drumragh catchment land use classification
June 1, 2010
53
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
54
112 142
321
243
322
231
412
112 142
243
312 321
322
321 312
321
243 412
Legend 243
112 - discont. urban 142 - sport & leisure 231 - pastures 243 - agric. & nat. veg. 312 - coniferous forest 321 - natural grasslands 322 - moors and heath 324 - trans. wood. 412 - peatbogs
321
0
Drumragh Corine 2000 Landuse Survey
1
2
3
4 Kilometers
© Crown Copyright and database rights OSNI EMOU 205.1 © Copyright NERC, Acknowledgements CEH, Monks Wood
±
Fig 7.01 Drumragh catchment land use classification map June 1, 2010
8.0
WATER QUALITY
Routine water quality monitoring within the Foyle and Carlingford areas is conducted by the Northern Ireland Environment Agency (NIEA) of the Department of the Environment for Northern Ireland and the County Councils in the Republic of Ireland (Donegal County Council and Louth County Council). Routine sampling is conducted regularly for both chemical and biological General Quality Assessments (GQA). In addition to the routine river monitoring carried out by the NIEA and the County Councils the Loughs Agency conducts proactive and reactive pollution investigations to investigate or highlight problems or potential problems which may have an effect on the aquatic environment and ultimately on the fish species and aquatic habitats. In 2007 the Loughs Agency instigated a programme of monitoring at the tributary level for assessments of chemical and biological water quality. Three stations on tributaries of the Drumragh River and four stations on tributaries of the Owenreagh River were monitored for chemical water quality parameters including Biological Oxygen Demand (BOD), Suspended Solids, Ammonia and Phosphorous. Biological water quality was assessed using the Biological Monitoring Working Party (BMWP) a biotic scoring index.
Fig 8.0 Loughs Agency chemical water quality testing in the laboratory
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
The Loughs Agency also maintains a mobile pollution response unit containing aerating equipment and absorbent and non absorbent booms for oil and chemical spills. The unit can be rapidly deployed to the site of a pollution incident. Water Quality Parameters The following water quality parameters are monitored through the Loughs Agency monitoring programme and determined from water samples in the laboratory: •
Biochemical Oxygen Demand (BOD)
•
Ammonia
•
Phosphorus
•
Suspended Solids
BOD Any organic matter discharged into a river provides an immediate source of food for bacteria. These bacteria will break down the organic matter eventually into simple compounds such as carbon dioxide and water. Biochemical Oxygen Demand or Biological Oxygen Demand (BOD) is a chemical procedure for determining how fast biological organisms use up oxygen in a body of water. It is considered as an indication of the quality of a watercourse Ammonia (NH3) Ammonia is generally found in small amounts in rivers and streams. This is due to microbiological activity and the resultant reduction of compounds containing nitrogen. High levels of ammonia can occur as a result from sewage pollution and have detrimental impacts on fish species. Phosphorus (PO4) The over-loading of nutrients such as phosphorus in watercourses often leads to a process known as eutrophication. Eutrophication is a major environmental issue in Irish rivers and lakes. Sources of phosphorus include agricultural fertilizers and household detergents. Suspended Solids Particulate matter may be organic or inorganic in nature. Organic solids may consist of algal growths, indicative of eutrophic conditions. Inorganic solids generally are the result of discharge washings from sand and gravel extraction activities or quarries. Suspended solids can affect plant growth and fish habitats. June 1, 2010
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
The following parameters are also recorded at each sample station by means of an electronic measuring probe: •
pH
•
Temperature
•
Dissolved Oxygen
•
Conductivity
pH This is a measure of the hydrogen ion concentration of a solution and therefore an indication of whether a liquid is acid or alkaline. The pH scale ranges from 0 (very acid) to 14 (very alkaline), with results generally influenced by geological conditions. Fish can be susceptible to changes in pH. Low pH levels are generally found in catchments with high forestry operation impacts. Temperature The effect of changes in temperature on living organisms, such as fish, can be critical. Thermal discharges from urban and industrial sources can lead to temperature increases in watercourses and increased stress on aquatic habitats and associated species. Dissolved Oxygen Sufficient levels of oxygen saturation in fresh waters are generally an indication of good ecological status and ideal for fish life. The main point to remember about oxygen solubility is that it has an inverse relationship with temperature. This helps explain why DO levels are generally lowest during summer low flow conditions, increasing the risk of pollution from discharges at this time. Conductivity The conductivity or electrical conductivity of a watercourse is a measure of its ability to conduct an electric current. Electrical conductivity estimates the amount of total dissolved salts, or the total amount of dissolved ions in the water. Electrical Conductivity is controlled by geology and any variations may be sourced to increased ions from wastewater from sewage treatment plants or urban run-off from roads.
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Fig 8.01a Drumragh catchment average suspended solids results 2009. Values are in mg/l
Fig 8.01b Owenreagh South catchment average suspended solids results 2009. Values are in mg/l
Fig 8.02a Drumragh catchment Ammonia results 2009. Values are in mg/l
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Fig 8.02b Owenreagh South catchment Ammonia results 2009. Values are in mg/l June 1, 2010
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Fig 8.03a Drumragh catchment phosphorous results 2009. Values are in mg/l June 1, 2010
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Fig 8.03b Owenreagh catchment phosphorous results 2009. Values are in mg/l June 1, 2010
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Fig 8.04a Drumragh catchment Biological Oxygen Demand (BOD) results 2009. Values are in mg/l June 1, 2010
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Fig 8.04b Owenreagh South catchment Biological Oxygen Demand (BOD) results 2009. Values are in mg/l June 1, 2010
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DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Fig 8.05a Drumragh catchment Biological Monitoring Working Party results 2009 June 1, 2010
66
DRUMRAGH RIVER, OWENREAGH S AND TRIBUTARIES CATCHMENT STATUS REPORT
Fig 8.05b Owenreagh South catchment Biological Monitoring Working Party results 2009 June 1, 2010
67
Prior to 2008 NIEA employed the General Quality Assessment (GQA) system to classify and monitor the chemical and biological water quality of the rivers of Northern Ireland. With the implementation of the Water Framework Directive a new approach to freshwater classification has been adopted following the United Kingdom Technical Advisory Group (UKTAG) guidelines developed for WFD implementation. An overall classification status for a water body is obtained by the amalgamation of biological, chemical and physical elements. Fig. 8.06 details how these elements combine to create ecological and chemical statuses which are then combined to create the overall surface water status.
Surface Water Status
Ecological Status Lowest class element
Biological quality elements H H H H G M P B
G M P B
G M P B
G M P B
General chemical & physio chemical quality elements H G M
H G M
H G M
H G M
Specific Pollutants gH gH gH gH gH M M M M M
Lowest class element H M
H G M P B
g
Hydromorphological quality elements H G
H G
H G
Lowest of chemical and ecological status
H G
Lowest class element
Chemical Status Priority substances & other EULevel dangerous substances G F
G F
G F
G F
G F
H G M P B
G F
G F G F
Lowest class substance
G M
H G M P B gH F
High Good Moderate Poor Bad Good or better Failing to achieve good water chemical status
Fig. 8.06: How the different water quality element results are combined to classify ecological status, chemical status and the overall surface water status: Adapted from the ‘Recommendations on Surface Water Classifications Schemes for the purposes of the Water Framework Directive’ UKTAG 2006.
The ecological status is determined primarily by the lowest class of the biological component. The general and physiochemical element can lower the status to moderate only. If both these elements are classified as high the hydromorphological
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element can only lower the overall ecological status to good. Whilst the ecological status has five classes (High, Good, Moderate, Poor and Bad), the chemical status has two (High and Moderate). The lowest status of the two determines the overall surface water status. This is termed the ‘one out – all out’ principle. Ecological Status: Classification of Quality Elements The various elements monitored for ecological classification are listed in table 8.07. Biological General/Physiochemical Hydromorphological 1. Macroinvertebrates 1. Dissolved Oxygen (% 1. Quantity & dynamics of water 2. Macrophytes Saturated) flow 3. Phytobenthos 2. Soluble Reactive 2. Connection to groundwater 4. Fish Phosphorus (SRP) 3. River continuity 3. pH 4. River depth & width variation 4. Specific Pollutants 5. Structure & substrate of the (includes ammonia) river bed. 6. Structure of the riparian zone Table 8.07. Quality elements which are monitored for the ecological status.
Biological Quality Elements Macro-invertebrates Different species of macro invertebrates are more sensitive to specific forms of pollution and therefore environmental quality ratios (EQRs) based on biological results may be used to assess water quality. Macro invertebrates are also the dominant prey of both salmonid and some non salmonid fish species. The measure of diversity of a macro invertebrate community can be a more reliable indicator of the pollution pressures within a catchment than relying solely on an assessment of chemical water quality. The impacts of pollution on a macro invertebrate community are longer lasting and can highlight intermittent pollution impacts that may be missed through chemical water quality monitoring. RIVPACS had been previously used to classify the biological quality of a site in terms of Macroinvertebrates. This has since been updated to meet WFD requirements and is called the Rivers Invertebrate Classification Tool (RICT). RICT utilises the same principle of a biotic scoring system to produce the EQRs on which the classes are based: EQR Taxa = BMWP Observed number of Taxa BMWP Predicted number of Taxa (As derived from RICT) EQR ASPT = BMWP Observed ASPT (Average Score Per Taxon) BMWP Predicted ASPT (As derived from RICT
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Class High Good Moderate Poor
ASPT EQR 0.97 0.86 0.75 0.63
NTAXA EQR 0.85 0.71 0.57 0.47
Table 8.08. Environmental Quality Ratio classifications for ASPT and NTaxa.
Macrophytes Macrophytes (aquatic vegetation) have been included in the classification as a measure of the effects of nutrient enrichment. The tool employed is Leafpacs which assesses species composition, diversity and abundance. Diatoms Diatom (microscopic organisms) species presence and relative abundance are also indicative of nutrient enrichment in both rivers and lakes. To assess the effect of these on the ecological status the Diatoms Assessment for Rivers and Lakes Ecological Quality (DARLEQ) tool has been developed which classifies on levels of nutrient sensitivity and tolerance. The higher the EQR the more sensitive diatom species present. A minimum of three samples over several years is necessary for this classification resulting in few water bodies being classified at present. Class High Good Moderate Poor Bad
Diatoms EQR 0.93 0.78 0.52 0.26 0
Macrophytes EQR 0.8 0.6 0.4 0.2 0
Table 8.09. Environmental Quality Ration Classifications for Diatoms and Macrophytes.
Fish At present there is no tool available for the classification of fish. It has been determined by expert judgement based on the quantitative electrofishing surveys undertaken by the Loughs’ Agency (Foyle and Carlingford Areas) and AFBI (for other rivers in Northern Ireland).
General Chemical and Physiochemical Quality Elements The general chemical elements required for WFD purposes are Dissolved Oxygen (% saturated), pH, and Soluble Reactive Phosphorus (SRP). Notably BOD is no longer used to classify a water body. It is still being monitored for investigative purposes where DO standards are not being met. In addition to these elements a number of ‘specific pollutants’ were also to be identified from a WFD list. These are pollutants which are being discharged in significant quantities. Of particular importance from a fishery aspect is Ammonia. There are 18 other pollutants listed (Full list detailed in NIEA’s Rationale for Water Framework Directive Freshwater Classification). June 1, 2010
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Class
High Good
DO (% saturation) (10 – percentile) 80 75
Moderate
64
Poor
50
pH
(5 & 95 percentile) >=6 to <=9 4.7 (10 percentile) 4.2 (10 percentile)
SRP (µg/l) (annual mean) 20 40
Ammonia (mg/l)
150
0.75
500
1.1
0.2 0.3
Table 8.010. Classification for General Chemical & Physiochemical Quality Elements.
Hydromorphological Elements Hydromorphological elements have been incorporated into the classification system to assess the impact that morphological alterations (e.g. sediment removal and channelisation) have on the ecological status of a river. The procedure employed to classify these elements is based on the previous NS Share method, Rapid Assessment Technique (RAT). The new method is the River Hydromorphological Assessment Technique (RHAT) and has been developed to be fully compliant with the WFD. Chemical Status: Classification of Quality Elements. Although chemical elements are already being assessed for the ecological status, the Chemical Status refers solely to those chemicals which have been defined as priority substances which are ‘those which present a significant risk to or via the aquatic environment’. These include Pentachlorophenol, Carbon Tetrachloride, Aldrin, Isodrin and Napthalene. The full list and their Environmental Quality Standards (EQS) are detailed in the framework’s ‘daughter’ Directive 2008/105/EC. The principal objective of the Water Framework Directive is to achieve good surface water status in all water bodies by 2015. The classification of the water bodies are to be published in the River Basin Management Plans, the first of which was published in Dec 2009. The directive has separate classification schemes for heavily modified water bodies, and protected areas. Heavily modified water bodies have been classified on their ecological potential, details of which are available on the NIEA website (www.nienvironment.gov.uk/wfd). For protected areas (e.g. River Foyle and its tributaries) maps are to be included in the River Basin Management Plans to indicate whether the objectives, established through legislation to define these areas, have been achieved. Similar classification methods are in use in the Republic of Ireland for WFD monitoring. The Habitat’s Directive (92/43/EEC) indicates that the water quality in these protected areas should achieve targets that are necessary for the designated species. The favourable conditions specific for salmonid rivers have been based on publications from Conserving Natura 2000 Rivers, the European Life Series, Ecology Series; No 7 Ecology of the Atlantic Salmon, Salmo Salar L (Table 9.11). June 1, 2010
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Parameter BOD (mg/l) Ammonia (mg/l) Dissolved Oxygen % Saturation Unionised Ammonia (mg/l) Suspended Solids (mg/l) Nursery Grounds Migratory Passage Soluble Reactive Phosphorus (mg/l)
Level 2.5 0.25 80
Percentile 90 90 10
0.025
95
10 25
-
Background
-
Reason High Status High Status High Status Favourable Conditions Habitat Forming Specific for Atlantic Salmon
Specific for Atlantic Salmon
Table 8.011. Favourable condition targets for Atlantic salmon
Figure 8.012. Flattened mayfly nymph from the order ephemeroptera high scoring macro invertebrate indicative of good water quality
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Figure 8.013a. Overall WFD surface water status for the Drumragh catchment 2009
Figure 8.013b. Overall WFD surface water status for the Owenreagh catchment 2009
8.1
WFD Fish Classifications 2009
The Loughs Agency is monitoring freshwater fish within the Foyle and Carlingford areas for reporting under the WFD. Working under the direction of the Northern Ireland WFD Fish Group (composed of NIEA, Loughs Agency, AFBI and DCAL personnel) surveillance monitoring stations are surveyed for fish populations once during each WFD reporting cycle. Seven Water Framework Directive fish surveillance monitoring stations were surveyed within the Loughs Agency jurisdiction in 2009. 0% were classified as high status, 43% classified as good status, 43% as moderate status 14% as poor status and 0% as bad status.
Loughs Agency/Foyle and Carlingford Area WFD Fish Classification 2009 (N = 7) 14%
High Good 43%
Moderate Poor
43%
Bad
Figure 8.11. LA fish classification 2009 based on seven sites surveyed within the Foyle and Carlingford areas
In the absence of a finalised fish in rivers classification tool (currently under development) professional judgement has been used to classify selected river sites for fish. These have then been incorporated into ecological status classifications and final surface water classifications. Data collection was conducted in the field during the summer of 2009 and involved the use of a quantitative electrofishing methodology commonly used for wadable rivers. This technique requires the netting off of a small section of river approximately 100m² using stop nets. Removal sampling is then conducted utilising electrofishing equipment with the numbers, age class and species of each fish being recorded for each pass. After an appropriate depletion has been achieved, which facilitates a density estimation to be made all fish are returned alive to the river.
Figure 8.12. WFD fish surveillance monitoring stations in the Foyle system
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Figure 8.13. WFD fish classifications in the Foyle system June 1, 2010
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In addition to directed WFD fish surveillance monitoring the Loughs Agency has collated other suitable fishery data collected from 2005-2009 and derived WFD fish classifications from this. Examples of this data is outlined below. Fish ing 1st 2nd 3rd
Sal 0+ 1 0 0
Tro 0+ 9 1 0
Tro 1+ 12 0 0
Eel
Lamp
Minnow
Stoneloach
Total
3 1 0
Stickle back 2 4 0
1 1 0
6 7 0
12 7 0
46 21 0
Tot
1
10
12
2
13
4
6
19
67
Table 8.14 Depletion sampling results from quantitative electrofishing survey Owenreagh South Catchment on the Creevan Burn 2009
Number of Fish
Fish Species and Numbers Caught, Creevan Burn Control Site 2009 20 15 10 5 0
19 13
12
10
Salmon 0+
Trout 0+
Trout 1+
Eel
6
4
2
1
Lamprey
Minnow Stickleback
Stone Loach
Fish Species
Table 8.15 Species and numbers caught
Numbers of Fish/100m²
Density Estimate of Fish Species (Creevan Burn Control) 25 18
20
16
15
11 8
10 5
2
3
5 1
0
Fish Species Table 8.16 Density of species by age class per 100m2
10
19
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Length Weight Relationship of Trout 0+ and Trout 1+ Creevan Burn Control (N=21) 160 140
y = 2E‐05x2.9162 R² = 0.9863
Weight (g)
120 100 80 60 40 20 0 0
50
100
150
200
250
Length (mm)
Figure 8.17 Length frequency distribution of juvenile trout
Length Frequency of Trout 0+ and Trout 1+ Creevan Burn Control (N=21) 4
Frequency
3
2
1
47 53 59 65 71 77 83 89 95 101 107 113 119 125 131 137 143 149 155 161 167 173 179 185 191 197 203 209 215 221
0
Length (mm)
Figure 8.18 Length weight relationship of juvenile trout
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9.0
CONSERVATION AND PROTECTION
The Loughs Agency continues to carry out an active fishery protection role throughout the catchments of the Foyle and Carlingford areas including the sea area, River Foyle and on all tributaries. Tables 9.0 and 9.01 outline the number of patrols and some duties carried out by the Loughs Agency staff in the Drumragh catchment and seizures for the Foyle area. A team of Fishery Officers are responsible for the Drumragh and Owenreagh South catchments splitting their time between the Strule catchment, Camowen catchment, Fairywater catchment, Owenreagh South catchment and the standing waters within the Loughs Agency southern zone. This is in addition to regular fishery protection patrols on the River Foyle. Year
No of Patrols
No of Licence Checks
Joint Patrols
On-site Inspections
2002 2003 2004 2005 2006 2007 2008 2009
25 30 48 40 21 48 34 73
41 48 67 127 58 127 209 184
15 9 8 10 0 22 18 11
123 128 103 186 259 247 153 38
Table 9.0. Breakdown of conservation and protection duties in the Drumragh catchment 2002-2009.
Year
2009
2008
2007
2006
2005
2004
2003
Nets
128
111
100
97
114
181
198
Salmon
6
46
56
91
118
130
155
Rod & Reel
96
139
85
26
10
16
12
Vehicles
0
1
0
2
1
1
0
Table 9.01 Seized nets, salmon, rod/reels and vehicles in the Foyle system 2003-2009
Year
Nets
Salmon/Trout Rod/Reel
Vehicles
Boats
2006
0
0
0
0
0
2007
0
0
2
0
0
2008
0
0
1
0
0
2009
0 (0)
0 (0)
0 (1)
0 (0)
0 (0)
Table 9.02 Seizures in the Drumragh (Owenreagh South in brackets) catchment 2006-2009
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9.1
Habitat Improvement Works
In addition to the traditional protection duties carried out by the Loughs Agency staff conservation and improvement of habitat has been increasing over recent years. Over time man has imposed significant changes on the natural courses of many rivers and flood plains. The driving forces behind these changes have included amongst others; arterial drainage schemes to provide more suitable land for agricultural purposes, urban sprawl, infrastructure expansion (roads etc.), flood defences, water abstraction and hydro power generation. All have had a significant impact on the natural meanderings and discharges of rivers and tributaries resulting in faster runoff of floodwaters ultimately leading to a change in the morphology and flow regime of rivers and resultant impacts on fisheries. While all these processes have had some impact within the Foyle system, it is considered to be a relatively natural system with natural river structure present in the catchments headwaters. In areas that have been altered methods for reinstating lost habitat are investigated and where appropriate action taken. In 2009 a stretch of the Routing Burn, within the Drumragh catchment, which was noticeably suffering from erosion, cattle trampling and lack of proper fishery habitat was identified. An improvement scheme was developed and with co-operation with the local landowner, 100 meters of revetment, 675 metres of riverside fencing, 14 habitat units and a culvert were constructed. Total cost = £15,870. An improvement scheme was also implemented on the Fintona River, again an area of the river which was suffering from erosion was identified. This erosion was occurring in a very productive spawning area, which had the potential to silt up the spawning beds below. A scheme was carried out which included rock revetment, 400 metres of riverside fencing and the planting of 100 native species of trees. Total cost of this project was £9,821. Also in 2009 the Loughs Agency in partnership with Blacksessiagh Regeneration Group instigated a programme of in channel and riparian habitat improvements on the Creevan Burn a tributary of the Owenreagh South. Works consisted of riparian fencing and buffer zone creation and habitat unit creation incorporating spawning gravel and nursery stone placement to improve the potential carrying capacity for native fish species within this reach.
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In 2007 a series of in-channel and riparian habitat improvement measures were conducted on the Fintona River and Seskinore River, both tributaries of the Drumragh River. The schemes were designed to reduce fine sediment input to the watercourses by protecting banks and installing appropriate fencing. Nursery habitat was also improved by introducing suitable substrate to the rivers. Where the channel had become over widened due to either past arterial drainage schemes or persistent trampling by cattle the base width was reduced by the installation of low level channel restrictors designed to mimic a more natural channel morphology increasing water depth and speed more suited to supporting good salmonid populations. The pictures below (Fig 9.1) provide some examples of the type of work carried out.
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Fig 9.1. Examples of in-stream habitat improvements on the Seskinore River and Fintona River
10.0 ENVIRONMENTAL ISSUES Some environmental issues affecting water quality have already been outlined previously. The following list presents some of the main habitat pressures to salmonids within the Foyle system: • • • • •
•
• •
Agricultural activities – enrichment from natural and artificial fertilisers often make their way into watercourses, enhancing problems with eutrophication. Forestry activities – planting and felling operations can lead to increased loading of suspended solids in watercourses. Established forestry as a major upland land use has been attributed to increased acidification. Barriers to migration – a range of natural and anthropogenic features on rivers can lead to barriers for migrating salmonids and other fish species. These can include weirs and hydro-electric schemes. Gravel removal – gravel is extremely important for the creation of redds for spawning fish. Removal of gravel from the river bed in sensitive areas can destroy potential spawning and nursery habitat. Quarrying activities – the extraction of aggregates such as rock, sand and gravel has the potential to cause increased levels of suspended solids in nearby watercourses. Sufficient mitigation measures should be in place at such sites to trap increased sediment loads entering rivers and streams. Abstraction – water abstraction from watercourses for a range of uses is increasing throughout the Foyle and Carlingford catchments. Unless appropriately assessed and licenced, these activities have the potential to reduce residual flow levels and alter the ecological status of our rivers. This is even more concerning in the light of climate change. Peat harvesting – Peat harvesting still occurs in small upland pockets throughout the Foyle system. It has the potential to increase sediment loading in receiving waters. Sewage treatment – sewage and waste water treatment works are under considerable pressure with the increase in urban development in our towns
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•
• • • •
and villages. Several inadequate systems throughout the Foyle system continue to pollute rivers. Hydropower – small-scale hydropower schemes are beginning to appear on rivers throughout the Foyle and Carlingford catchments. Baseline fishery data must be provided to allow for sufficient assessment of any proposed scheme, unless located above an impassable fish barrier. Urban development – the expansion of large-scale housing developments and the associated pressures on waste water and sewage treatment works are a potential source of water pollution in the event of overflows. Drainage and canalisation – these have direct impacts on the quality of available fishery habitat within the catchments. Canalisation in particular can lead to the removal of important spawning, nursery or holding areas of rivers. Industrial discharges – larger urban areas with industrial discharges have the potential to cause pollution through toxic discharges and can alter the temperature of the watercourse. Septic tanks – a proliferation of single dwellings and their septic tanks is an ongoing area of concern. Initial research from parts of the Foyle system indicate that this is major contributor to decreased water quality and local increases in suspended solids.
11.0 DESIGNATED AREAS The European Commission Directive on the Conservation of Natural Habitats and of Wild Fauna and Flora (EU Habitats Directive 92/43/EEC) requires that all member states designate Special Areas of Conservation (SACs) in order to protect threatened habitats and species. The European Commission Directive on the Conservation of Wild Birds (Birds Directive 79/409/EEC) also requires the designation of Special Protected Areas (SPA’s). Together the designated SAC’s and SPA’s create the NATURA 2000 network of protected sites. A number of rivers have been designated as SAC’s both in Northern Ireland and in the Republic of Ireland. The River Foyle and selected tributaries have been designated as a Special Area of Conservation (SAC’s). The Drumragh and Owenreagh South catchments are not included in this designation. The River Foyle and its tributaries have been designated to protect its Atlantic salmon populations in freshwater, Otter populations and its floating vegetation habitat dominated by water crowfoot. Cranny Bogs and Tonnagh Beg Bog have both been designated as SAC’s and are partially within the Drumragh catchment. They are both examples of active raised bog, an important habitat type with species of community interest present.
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12.0 GENETIC STUDY A baseline genetic survey was carried out in the Foyle system in 2003 and a resurvey conducted between 2006 and 2008 to analyse the populations of Atlantic salmon present within the Foyle catchment. Results confirmed the existence of genetically distinct populations between and within the rivers and tributaries of the Foyle area. An understanding of these genetically differentiated populations is required to facilitate appropriate management of conservation measures and the commercial/recreational fisheries. The report concluded that genetic diversity is high between and within the various salmon populations present in the Foyle system. Each population has evolved over time creating distinct populations (with some gene flow from straying fish) that are best suited to the conditions present in a particular river or tributary. The non-uniform nature of the populations adds to the diversity of life history strategies exercised by Foyle salmon. Distinct differences such as run-timing and age at smolting can act as natures insurance policy to any catastrophic events which would threaten a homogenous population. The report stated that the current genetic structure and diversity of Foyle salmon is representative of what might be regarded as the native structure of wild salmon populations. The maintenance of genetic diversity is a core requirement for the longterm sustainability of wild populations, preserving the biodiversity of the wild salmonids of the Foyle system is therefore a primary objective of the Loughs Agency.
13.0 POLLUTION MONITORING The Loughs Agency has a statutory obligation to monitor the pollution of watercourses. In conjunction with the Northern Ireland Environment Agency all reported pollution incidents are investigated.
14.0 FISHERY OFFICERS DRUMRAGH AREA REPORT 2009 In 2009 Fishery Officers continued their work within the Drumragh and Owenreagh South catchments. Regular patrols have been undertaken by Fishery Officers over the period of this report. These patrols have been both pro-active and re-active in nature. These patrols have resulted in pollution investigations and the preparation of files for prosecution. On-site inspections excluding these investigations resulted in 38 onsite inspections within the Drumragh catchment. It has been noted that there has been a marked increase in the number of incidents involving slurry. This may be due to; • •
Inadequate on-farm storage capacity The ban on the spreading of slurry between 31th October and the 1st February. June 1, 2010
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•
Inclement milder winters
Water quality monitoring was carried out on a monthly basis. Any issues that have been highlighted have been investigated through premises visits and proactive patrols in these areas. Fishery protection in the Southern area over the period of this report has consisted of patrols on the rivers and loughs, checking of salmon retailers and dealers. During patrols on the rivers and loughs, a number of angling offences have been detected by Loughs Agency Fishery Officers including; non production of licence, use of unlawful baits, exceeding bag limits, use of more than one rod, non tagging of salmon or misuse/ tampering with tags. The detection of these offences has led to seizures of fishing equipment and the preparation of files for prosecution. The salmon spawning areas were patrolled on a nightly basis during the vulnerable period before spawning took place and for a period after until most fish were thought to have migrated back downstream. Patrols were undertaken with the assistance of Private Riverwatchers from Omagh Anglers Association. No illegal nets were seized in the Southern Area in 2009. All known salmon dealers and retailers were visited and premises inspected, including freezers, registers and receipts. A number of incidents of gravel extraction were detected over the period. Several warning letters have been sent to individuals who were identified. A number of survey’s were undertaken by Fishery Officers during 2009 these included; • • • • •
15.1
The completion of a habitat survey to the Drumragh/Owenreagh catchment. Redd counts within the entire catchment were completed. Annual electro-fishing survey was completed. A survey to the urban streams in and around Omagh to evaluate fishery potential. A survey to evaluate possible barriers to fish migration.
Foyle and Carlingford Areas Ongoing Actions for 2010
Good water quality is essential for the conservation of productive aquatic ecosystems. Fish populations rely on unpolluted water for survival and feeding. The Loughs Agency is committed to ensuring deleterious matter does not enter any watercourse. Routine monitoring is conducted throughout the Foyle and Carlingford areas. Proactive pollution visits and water quality monitoring will continue in 2009.
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Water quantity is becoming an increasingly important issue from a fisheries management perspective with continuing demand from a variety of sources including industry, hydro power generation and abstraction for meeting the ever growing needs of industry and the wider population. The Loughs Agency are aware of the conflicting needs of aquatic environments and water resource users and comment on development issues which may have an impact on the important aquatic resources of the Foyle and Carlingford areas with reference to national and international obligations. In-channel and riparian habitat improvement projects provide an important mechanism by which to improve and protect valuable fishery resources. Over recent years the Loughs Agency has developed a number of projects designed to improve the survival and production of robust populations of juvenile salmonid and other native fish species. These programmes will continue where funding is available, The Loughs Agency also encourages local stakeholder groups to source appropriate funding to develop collaborative habitat improvement projects. The Loughs Agency can provide advice and recommendations for in-channel and riparian improvements and are eager to facilitate the development of such programmes. Work is continuing to assess and record all Barriers to Migration within the catchments of the Foyle and Carlingford areas and these will be incorporated into the Loughs Agency Geographical Information System (GIS). Where finances are available the removal of artificial barriers will be investigated. Predation by cormorants and seals of economically important fish species continues to be a contentious issue. The Loughs Agency will continue to promote the development of a management strategy incorporating economic, social and environmental factors. The Loughs Agency will continue to monitor the salmon and inland fishery resources of the Foyle and Carlingford areas, utilising best practice methods including fish counters, juvenile population surveys and catch returns. The importance of the Atlantic salmon resource has been further highlighted by recent genetic studies which have identified the presence of genetically distinct populations of salmon between and within main river catchments. This information will be utilised when developing habitat improvement programmes to ensure the presence of a diverse resource capable of withstanding change. Invasive species in both aquatic and riparian habitats have become an important issue in fisheries management and in wider environmental management. Invasive species have the potential to significantly alter ecosystems and their function. The Loughs Agency is contributing towards the development and implementation of invasive species codes of practice.
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15.0 ACTIONS FOR 2010 In order to fully utilise the extensive data resources collected and held by the Loughs Agency on the fish populations and habitats of the Drumragh and Owenreagh South catchments it is necessary to focus attention on specific management objectives. The Loughs Agency has stated in its corporate plan 2008-2010 that it will conserve, protect, manage and improve the fisheries of the Foyle and Carlingford areas. By way of fulfilling these objectives a targeted series of actions utilising data collected over recent years will be implemented. Fishery owners and local angling clubs will continue to be consulted regarding any proposed works and stakeholder input sought. 15.2 Drumragh and Owenreagh South Catchments Potential Habitat Improvement Schemes for 2010 Potential schemes are currently being developed 15.3
Drumragh and Owenreagh South Catchments Specific Actions for 2010
•
Conduct annual fish population surveys and spawning surveys
•
Conduct ongoing water quality monitoring and investigate areas highlighted as being of concern
•
Develop potential habitat improvement projects including riparian buffer zone creation, fencing, native species planting and in-channel habitat improvements including spawning bed and nursery habitat improvement and pool creation.
•
Monitor forestry operations adjacent to watercourses or areas likely to impact on watercourses
•
Assist with Water Framework Directive fish monitoring programme
•
Monitor all sand and gravel extraction sites and onsite water management practices
•
Ensure all fish passes, dams and mill races meet required standards
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