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2008 Status Report: River Drumragh and Tributaries

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Drumragh River and Tributaries Catchment Status Report 2008

Loughs Agency of the Foyle Carlingford and Irish Lights Commission


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Drumragh River and Tributaries Catchment Status Report 2008

Report Reference LA/CSR/06/09

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 www.loughs-agency.org

Regional Office Dundalk Street Carlingford Co Louth Republic of Ireland Tel+353(0)42 938 3888 Fax+353(0)42 938 3888 carlingford@loughsagency.org www.loughs-agency.org Inside cover picture of hen salmon courtesy of Atlantic Salmon Trust

Written and Prepared by: Art Niven Rachel Scott Declan Lawlor Siobhán Sweeney 2


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Table of Contents 1.0

INTRODUCTION ........................................................................................................................... 6 Figure 1.0 Main salmon producing rivers and tributaries in the Loughs Agency, Foyle and Carlingford areas ............................................................................................................................. 7

1.1

The Drumragh Catchment....................................................................................................... 8

Fig 1.1 Head waters of a Foyle tributary ......................................................................................... 8 Fig.1.11 Drumragh River ................................................................................................................. 9 Fig 1.12 River Mourne ..................................................................................................................... 9 Fig 1.13 Foyle and Carlingford catchments illustrating the main rivers of the systems ............... 10 1.2

Atlantic Salmon and Sea Trout .............................................................................................. 11

1.3

Non Salmonid Fish Species.................................................................................................... 11

Fig 1.3 Sample of fish from the Foyle estuary............................................................................... 11 2.0

ATLANTIC SALMON STOCKS ...................................................................................................... 12

2.1

Redd Counts .......................................................................................................................... 12

Table 2.1 Redd counts for Foyle system and Drumragh catchment 2004/05 ‐ 2008/09 ............. 12 Fig 2.1 Redd counts for Foyle system and Drumragh catchment 2004/05 – 2008/09 ................. 13 Fig 2.11 Redd counts for Foyle system 1952/53 – 2008/09 ......................................................... 13 2.2

Juvenile Abundance .............................................................................................................. 14

Table 2.2 Loughs Agency semi‐quantitative electrofishing classification system ........................ 15 Fig 2.2 Drumragh catchment salmon fry index 1999‐2008 .......................................................... 15 Fig 2.21. The mean abundance of salmon fry in 17 catchments in 2008 ..................................... 16 Fig 2.22 Salmon 0+ electrofishing site classification 2008 ............................................................ 17 3.0

TROUT STOCKS .......................................................................................................................... 18 Fig 3.01 Drumragh catchment trout fry index 1999‐2008 ............................................................ 18 Fig 3.02. The mean abundance of trout fry in 17 catchments in 2008 ......................................... 19 Fig 3.03 trout 0+ electrofishing site classification 2008................................................................ 20

4.0

MARINE SURVIVAL .................................................................................................................... 21 Table 4.0 Marine survival rates for the River Bush of 1SW grilse ................................................. 21 Fig 4.0 Proposed marine survey areas for salmon in 2008 ........................................................... 22 Fig 4a RV Celtic Explorer SALSEA research cruise 2008 ................................................................ 23 Figure 4b Picture from the Irish Research Vessel Celtic Explorer ................................................. 23

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Figure 4c Rotary screw trap in position on the River Faughan ..................................................... 24 Table 4.01 Numbers and average weight and length of salmon smolts tagged........................... 24 Table 4.02 Recapture data from River Faughan CWT programme. .............................................. 25 Figure 4d Salmon smolt run timing and abundance from rotary screw trap sub sample ............ 25 Table 4.03 Age class of salmon smolts migrating from the Faughan catchment in 2004 ............ 26 Fig 4.01. Atlantic salmon smolts from the Faughan Catchment ................................................... 26 5.0

ADULT ABUNDANCE.................................................................................................................. 27

5.1

Recreational Fisheries ........................................................................................................... 27

Table 5.1 Declared rod catch returns for salmon and trout in the Foyle and Carlingford areas. . 27 Table 5.11 Declared catch from the Drumragh catchment ......................................................... 28 Fig 5.1 Recreational fisher............................................................................................................. 28 5.2

Commercial Fisheries ............................................................................................................ 28

Table 5.2 Declared catch from the commercial salmon fisheries 1998‐2008 .............................. 29 Fig 5.2 Commercial Fishing ........................................................................................................... 29 5.3

Counters ................................................................................................................................ 29

Fig 5.3 New weir constructed on the River Strule in Omagh. ....................................................... 30 Fig 5.31 Fish counting facilities at Sion Mills, River Mourne......................................................... 30 Table 5.3 River Strule fish counter figures 2007‐2008.................................................................. 30 Fig 5.32 Monthly fish counts on the River Strule September 2007‐2008 ..................................... 31 Table 5.31 Sion Mills fish counter figures 2002‐2008. .................................................................. 31 Fig 5.33 Monthly fish counts on the River Mourne 2004‐2008 as recorded at Sion Mills ........... 32 Fig 5.34 Annual fish counts on the River Mourne 1987‐2008 ...................................................... 32 5.4

Conservation Limits/Spawning targets ................................................................................. 33

Table 5.4 Upstream of Sion Mills estimated egg deposition 2002‐2007 ...................................... 33 6.0

HABITAT MONITORING ............................................................................................................. 34 Fig 6.0 Life cycle unit ..................................................................................................................... 34 Fig 6.01 Examples of spawning, nursery and holding habitats ..................................................... 34

7.0

LAND USE .................................................................................................................................. 35 Fig 7.0 Camowen catchment land use classification .................................................................... 35 Fig 7.01 Drumragh catchment land use classification map .......................................................... 36

8.0

WATER QUALITY........................................................................................................................ 37 Fig 8.0 Loughs Agency chemical water quality testing in the laboratory ..................................... 37 Fig 8.01 Drumragh catchment average suspended solids results 2008 ....................................... 40 Fig 8.02 Drumragh catchment Ammonia results 2008 ................................................................. 41

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Fig 8.03 Drumragh catchment phosphorous results 2008 ........................................................... 42 Fig 8.04 Drumragh catchment Biological Oxygen Demand (BOD) results 2008 ........................... 43 Fig 8.05 Drumragh catchment Biological Monitoring Working Party results 2007 ...................... 44 Table 8.0 chemical GQA class limiting criteria .............................................................................. 45 Table 8.01 Biological GQA class limiting criteria ........................................................................... 46 Figure 8.06 Flattened mayfly nymph from the order ephemeroptera ......................................... 46 8.1

Favourable condition tables, target levels ............................................................................ 47

Table 8.1 Favourable condition targets for Atlantic salmon......................................................... 47 Fig 8.1 Chemical General Quality Assessment (GQA) Drumragh catchment 2007....................... 49 Fig 8.11 Biological General Quality Assessment (GQA) Camowen catchment 2007 .................... 50 9.0

CONSERVATION AND PROTECTION .......................................................................................... 51 Table 9.0. Breakdown of conservation and protection duties ..................................................... 51 Table 9.01 Seized nets, salmon, rod/reels and vehicles in the Foyle system 2003‐2008 ............. 51 Table 9.02 Seizures in the Drumragh catchment 2006‐2008 ....................................................... 51

9.1

Habitat Improvement Works ................................................................................................ 52

Fig 9.1. Examples of in‐stream habitat improvements ................................................................. 55 10.0

ENVIRONMENTAL ISSUES.......................................................................................................... 55

11.0

DESIGNATED AREAS .................................................................................................................. 56

12.0

GENETIC STUDY ......................................................................................................................... 57

13.0

POLLUTION MONITORING ........................................................................................................ 57

14.0

FISHERY OFFICERS DRUMRAGH AREA REPORT 2008 ................................................................ 57

14.1 15.0

Fishery Officers Report ......................................................................................................... 58 ACTIONS FOR 2009.................................................................................................................... 58

15.1

Foyle and Carlingford Areas Ongoing Actions for 2009 ........................................................ 58

15.2

Drumragh Catchment Potential Habitat Improvement Schemes for 2009 .......................... 59

15.3

Drumragh Catchment Specific Actions for 2009 ................................................................... 60

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Drumragh River and Tributaries Catchment Status Report 2008 1.0

INTRODUCTION

The annual Drumragh River and Tributaries Catchment Status Report has been updated to include results collated on the fishery resources within the catchment in 2008 and reports and discusses additional environmental information which when combined can facilitate in the sustainable management of aquatic resources within the catchment. 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. Over recent years the catchment status reports have been consulted widely by a variety of stakeholders including local angling associations, fishery owners, statutory bodies, environmental consultants 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 2008 catchment status reports is aquatic and riparian habitats. Both habitats are essential for a balanced ecosystem ensuring that the biodiversity of wild salmonids and other native flora and fauna is preserved. Significant focus has been placed on aquatic resource management by a combination of national, European and international legislation and conventions. In 2009 the first River Basin Management plans produced under the European Union Water Framework Directive will outline a structure for classifying all water bodies as having good ecological status. This will be an iterative process over many reporting cycles with significant improvements in water quality expected over coming years. Partnership development and collaborative working has been highlighted as an essential mechanism to achieve this and the Loughs Agency is playing an active role as a significant stakeholder and manager of aquatic resources within the Foyle and Carlingford areas. In addition the European Union Habitats Directive and Birds Directive have resulted in the designation of Special Areas of Conservation (SAC) and Special Protection Areas (SPA). Together these designations have formed the NATURA 2000 network of protected sites. Throughout the Foyle and Carlingford areas there are significant areas designated as SAC or SPA. Under the SAC designation Atlantic salmon is one of the main species that led to the significant number of Foyle area tributaries being

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

designated. Designation provides an additional mechanism for the protection and conservation of these important aquatic ecosystems. Northern Ireland and the Republic of Ireland are also a signatory through their membership of the European Union to the North Atlantic Salmon Conservation Organisation (NASCO) convention for the conservation of salmon in the North Atlantic Ocean. Contracting parties are required to contribute towards the compilation and implementation of focus area reports the most recent of which was on the Protection Restoration and Enhancement of Salmon Habitat. The Loughs Agency provided input for areas within its jurisdiction.

Figure 1.0 Main salmon producing rivers and tributaries in the Loughs Agency, Foyle and Carlingford areas. Foyle 1 Burn Dennet, 2 Camowen, 3 Culdaff, 4 Deele, 5 Derg, 6 Drumragh, 7 Fairywater, 8 Faughan, 9 Finn, 10 Muff, 11 Glenelly, 12 Glenmornan, 13 Mourne, 14 Owenkillew, 15 Owenreagh East, 16 Owenreagh South, 17 Roe, 18 Strule, 19 River Foyle (tidal). Carlingford Only the Whitewater (10) has a consistent population of Atlantic salmon present. 1 Bessbrook, 2 Cassy Water, 3 Clanrye, 4 Ghann, 5 Greenore, 6 Killbroney, 7 Moygannon, 8 Newry, 9 Ryland, 10 Whitewater

Under the Foyle Fisheries Acts 1952 and the recent amendment by the Foyle and Carlingford Fisheries Act/Order 2007 there are various legislative requirements and offences including under the 2007 legislation a new offence of removal of any bed material from the freshwater portion of any river in the Foyle or Carlingford areas without consent of the Loughs Agency. This has provided an important control on activities likely to impact directly on aquatic habitats and indirectly on fish populations.

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

1.1

The Drumragh 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 Qiggery 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. 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 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 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 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.

Fig 1.1 Head waters of a Foyle tributary

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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.

Fig.1.11 Drumragh River

Fig 1.12 River Mourne

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Fig 1.13 Foyle and Carlingford catchments illustrating the main rivers of the systems and highlighting the Drumragh River and Tributaries

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 Drumragh 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, European Smelt, Shad and River/Brook and Sea Lamprey form an important part of the native fisheries biodiversity of the Drumragh catchment. 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

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 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. 2004/05

2005/06

2006/07

2007/08

2008/09

Foyle System

2412

5354

*1338

3039

5507

Drumragh Catchment

473

519

*252

238

392

19

10

*19

8

7

Drumragh as a % of Foyle

Table 2.1 Redd counts for Foyle system and Drumragh catchment 2004/05 - 2008/09. *Note 2006/07 had extremely poor water conditions for redd counting

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Drumragh Redd Count 6000 Drumagh Catchment

Number of Redds

5000

Total Foyle

4000 3000 2000 1000 0 2004/5

2005/6

2006/7

2007/8

2008/9

Year

Fig 2.1 Redd counts for Foyle system and Drumragh catchment 2004/05 – 2008/09. *Note 2006/07 had extremely poor water conditions for redd counting

Total Number of Redds in Foyle 1952/53 ‐ 2008/09 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 – 2008/09

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 2008 a total of 403 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 2.2 - 2.21 outline the salmon 0+ electrofishing results and site classifications for the Drumragh catchment in 2008. 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 AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 Salmon Fry Index 16 14 Average Fry/5 Minute Fishing

Salmon 0+ 12 10 8 6 4 2 0 1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

Year

Fig 2.2 Drumragh catchment salmon fry index 1999-2008. Note number of sites surveyed has fluctuated annually, the number of sites surveyed has stabilised since 2002.

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Summary of Salmon Fry Semi Quantitative Electrofishing Results 2008 35

30

Average Salmon Fry/5min

25

20

15

10

5

Catchment

Fig 2.21. The mean abundance of salmon fry in 17 catchments in 2008 from semi quantitative electrofishing.

16

Fairywater

Owenreagh S

Glenmornan

Deele

Foyle South

Drumagh

Camowen

Culdaff

Finn

Strule

Derg

Glenelly

Burn Dennet

Owenkillew

Owenreagh East

Roe

Faughan

0


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! (

! ( ! (

! (

! (

! (

! (

! (

! (

! (

! (

! (

! (

! ( ! (

! (

! ( ! ( ! ( ! ( ! ( ! (

Legend

! ( None (0) ! ( Poor (1 - 4) ! ( Fair (5 - 14) ! ( Good (15 - 24) ! ( Excellent (25 - 200) River

Drumragh Electrofishing Results for Salmon 0+ 2008

0

0.5

1

1.5

2 Kilometers

© Crown Copyright and database rights EMOUU205.1

±

Fig 2.22 Salmon 0+ electrofishing site classification 2008

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 Finn catchment and site classifications are displayed in Figs 3.0, 3.01, 3.02 & 3.03.

Fig 3.0 Electrofishing survey and trout parr

Drumragh Trout Fry Index Average Fry/5 Minute Fishing

7 6 Trout 0+ 5 4 3 2 1 0 1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

Year Fig 3.01 Drumragh catchment trout fry index 1999-2008. Note number of sites surveyed has stabilised since 2002.

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

25

Summary of Trout Fry Semi Quantitative Electrofishing Results 2008

Average Trout Fry/5 min

20

15

10

5

Fairywater

Drumagh

Owenreagh S

Camowen

Derg

Deele

Finn

Strule

Owenkillew

Culdaff

Owenreagh East

Roe

Glenelly

Burn Dennet

Faughan

Glenmornan

Foyle South

0

Catchment

Fig 3.02. The mean abundance of trout fry in 17 catchments in 2008 from semi quantitative electrofishing. Note Sites selected were biased towards salmon habitat.

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ( ! ! ( ! ( ! (

! ( ! (

! (

! (

! (

! (

! (

! (

! (

! (

! (

! (

! ( ! (

! (

! ( ! ( ! ( ! ( ! ( ! (

Legend

! ( None (0) ! ( Poor (1 - 4) ! ( Fair (5 - 14) ! ( Good (15 - 24) ! ( Excellent (25 - 200) River

Drumragh Electrofishing Results for Trout 0+ 2008

0

0.5

1

1.5

2 Kilometers

© Crown Copyright and database rights EMOUU205.1

±

Fig 3.03 trout 0+ electrofishing site classification 2008

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 4.0. Year of Smolt Cohort

Year of Returning 1SW Grilse

Marine Survival %

Pre 1996

Pre 1998

Circa 30%

2002

2003

5.9

2003 2004

2004 2005

4.3 4.6

2005

2006

4.2

2006

2007

13.0

2007

2008

7.5

Table 4.0 Marine survival rates for the River Bush of 1SW grilse (after exploitation at sea) pre 1996 and 2002-2007 smolt cohort. Data supplied by Agri Food and Bioscience Institute, River Bush Salmon Research Station

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

The figures outlined in table 4.0 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 will continue in 2009 to collect the necessary data to answer the questions listed above. Over 426 post smolts were caught by the two Irish cruises and 363 post smolts caught by the Faroese in the areas highlighted below. Further information and project details can be found at: http://www.nasco.int/sas/salsea.htm

Fig 4.0 Proposed marine survey areas for salmon in 2008

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Fig 4a RV Celtic Explorer SALSEA research cruise 2008

Figure 4b Picture from the Irish Research Vessel Celtic Explorer taken during the second SALSEA research cruise 16-24th May 2008

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 4.01 and 4.02 outline numbers of salmon smolts tagged from 2003-2008 and recapture data for 2003 and 2004. Year

No of Salmon Smolts Tagged

Average Length (mm)

Average Weight (g)

2003 2004 2005 2006 2007 2008

2113 2500 2210 1025 2062 1865

149 134 133 133 135 130

33.45 24.6 23.6 25.36 27.1 22.1

Table 4.01 Numbers and average weight and length of salmon smolts tagged on the River Faughan 2003-2008. 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 AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Year Tagged

Year Recaptured

Numbers Recaptured

Recapture Location

2003

2004

12

Greencastle, Burtonport, Malin Head, Belmullet and Torr Head

2004

2005

16

Greencastle, Malin Head, Donegal and Galway Bay

2005

2006

3

Greencastle

2006

2007

2

Greencastle and Ballycastle

Table 4.02 Recapture data from River Faughan CWT programme. Data for fish tagged in 2007 and recovered in 2008 will not be available until 2009.

600

River Faughan

2004 2005

Number of Salmon Smolts Trapped

500

2006 2007 400

2008

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

01‐May

29‐Apr

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 2004-2008. Breaks in data are due to closure of trap during high water conditions

25


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

In 2004 a detailed examination was carried out on the age class of migrating salmon smolts in the Faughan catchment, Table 4.03. Age at Smolting 1 2 3

% 13 83 4

Table 4.03 Age class of salmon smolts migrating from the Faughan catchment in 2004

Fig 4.01. 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.

26


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 seasons 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

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.

27


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Year

Declared Catch Drumragh Catchment Salmon 17 25 16 16 84 26 54 103

2001 2002 2003 2004 2005 2006 2007 2008

Declared Catch Drumragh Catchment Sea Trout 0 0 0 0 14 5 13 33

Table 5.11 Declared catch from the Drumragh catchment for salmon and sea trout 2001-2008

Fig 5.1 Recreational fisher

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 28


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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. Year

Drift Catch

Draft Catch

1998 1999 2000 2001 2002 2003 2004 2005 2006 *2007 2008

31296 15397 22333 13500 28851 15741 12800 13391 6160 2598 1248

11141 7893 10339 9476 11917 16991 9490 12143 6031 2774 2924

Total Drift and Draft 42437 23290 32672 22976 40768 32732 22290 25534 12191 5372 4172

Table 5.2 Declared catch from the commercial salmon fisheries 1998-2008. Note 100% rate of catch returns. * Reduced numbers of commercial nets operating in the Foyle area from 2007

Fig 5.2 Commercial Fishing. Draft netting on the tidal River Foyle and drift netting in Lough Foyle

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 29


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 5.3 and 5.31.

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

Year

Number of fish >45cm

2007

126

2008

207

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

30


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

River Strule Fish Counter Figures 2007 & 2008 90 2008

80

2007 Number of Fish > 45cm

70 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 River Strule September 2007-2008 as recorded at Omagh

Year

Number of fish >45cm

2002

12991

2003

12129

2004

10270

2005

9397

2006

9926

*2007

*3714

*2008

*3452

Table 5.31 Sion Mills fish counter figures 2002-2008. *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.

31


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

River Mourne Fish Counter Figures 2004 ‐2008 4500 4000 Number of fish >45cm

3500 3000

2004

2500

2005

2000

2006

1500

2007

1000

2008

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

River Mourne Electronic Fish Counters Figures 1987‐2008 25,000

Number of Fish > 45cm

20,000

15,000

10,000

5,000

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

1997

1996

1995

1994

1993

1992

1991

1990

1989

1988

1987

0

Fig 5.34 Annual fish counts on the River Mourne 1987-2008

32


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 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. Year

No of Fish Across Counter

Estimated Egg Deposition

2005 2006 *2007 *2008

9397 9926 *3714 *3452

10,571,625 11,166,750 *4,178,250 *3,883,500

Table 5.4 Upstream of Sion Mills estimated egg deposition 2002-2007. *Note 2007 and 2008 figures are minimum estimates of escapement due to high water levels resulting in the bypassing of the Sion Mills counting channels.

33


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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

Fig 6.01 Examples of spawning, nursery and holding habitats

34


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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

35


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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

36


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 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

37


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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

38


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

result of discharge washings from sand and gravel extraction activities or quarries. Suspended solids can affect plant growth and fish habitats. 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.

39


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

06-03 06-02

06-01

Legend 0 - 10 Favourable Nursery Conditions 10 - 25 Acceptable Migratory Passage > 25 Unacceptable River

Drumragh Mean Suspended Soilds Results 2008

0

0.5

1

1.5

2 Kilometers

© Crown Copyright and database rights EMOUU205.1

±

Fig 8.01 Drumragh catchment average suspended solids results 2008. Values are in mg/l

40


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

06-03 06-02

06-01

Legend 0 - 0.25 Very Good 0.25 - 0.6 Good 0.6 - 1.3 Fairly Good 1.3 - 2.5 Fair 2.5 - 9 Poor > 9 Bad River

0

Drumragh 90th Percentile Ammonia Results 2008

1

2

3

±

4 Kilometers

© Crown Copyright and database rights EMOUU205.1

Fig 8.02 Drumragh catchment Ammonia results 2008. Values are in mg/l

41


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

06-03 06-02

06-01

Legend 0 - 0.20 Acceptable Conditions > 0.20 Unacceptable Conditions River

Drumragh Mean Phosphorus Results 2008

0

0.5

1

1.5

2 Kilometers

© Crown Copyright and database rights EMOUU205.1

±

Fig 8.03 Drumragh catchment phosphorous results 2008. Values are in mg/l

42


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

06-03 06-02

06-01

Legend 0 - 2.5 Very Good 2.5 - 4 Good 4 - 6 Fairly Good 6 - 8 Fair 8 - 15 Poor >15 Bad River

Drumragh 90th Percentile BOD Results 2008

0

0.5

1

1.5

2 Kilometers

© Crown Copyright and database rights EMOUU205.1

±

Fig 8.04 Drumragh catchment Biological Oxygen Demand (BOD) results 2008. Values are in mg/l

43


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

06-03 06-02

06-01

Legend 0 -30 Bad Quality 30 - 60 Poor Quality 60 - 100 Fair Quality >100 Good Quality River

0

0.5

1

1.5

2 Kilometers

Drumragh BMWP Results 2008

© Crown Copyright and database rights EMOUU205.1

±

Fig 8.05 Drumragh catchment Biological Monitoring Working Party results 2008

44


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

NIEA routinely monitor both the chemical and biological water quality within the rivers of Northern Ireland. In relation to chemical monitoring an extensive network of sampling stations are monitored for a variety of chemicals. The General Quality Assessment (GQA) is defined by limits for the concentrations of Biological Oxygen Demand (BOD), ammonia and dissolved oxygen (DO). The measures listed are indicators of the affect on water quality by waste water discharges and agricultural run-off containing organic material. Water quality can be affected by a variety of sources and the GQA determinands provide a recognised assessment of water quality. The overall GQA class assigned to a section of river is based on the worst performing of the three measures (BOD, ammonia and DO). Table 8.0 outlines the standards for the chemical GQA. GQA Class

A (Very Good) B (Good) C (Fairly Good) D (Fair) E (Poor) F (Bad)

Dissolved Oxygen (% Sat) 10percentile 80 70 60 50 20 <20

BOD (mg/l) 90-percentile

Ammonia (mg/l) 90-percentile

2.5 4 6 8 15 -

0.25 0.6 1.3 2.5 9.0 -

Table 8.0 chemical GQA class limiting criteria

The above table can be summarised as follows: for BOD and ammonia the section of river should contain less than the stated levels for at least 90% of the time. DO levels must not fall below the stated levels for more than 10 percent of the time. In relation to biological monitoring an extensive network of sampling stations is also routinely monitored. The biological GQA is defined by observed measures of the abundance and diversity of macro invertebrates (for example freshwater shrimps, insect larvae and molluscs) compared to expected values as derived from a UK computer model adapted for Northern Ireland called River Invertebrate Prediction and Classification System (RIVPACS) Different species of macro invertebrates are more sensitive to specific forms of pollution and therefore environmental quality indices (EQIs) 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.

45


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Biotic scoring systems have been developed to assign a score based on a standardised system to each sample site. One such system is the Biological Monitoring Working Party (BMWP). Generally the higher the BMWP score the better quality of the macro invertebrate community which reflects better water quality. Based on a combination of biotic scoring systems biological GQA classes are assigned to sections of river. The two EQIs used are as follows:

EQItaxa = BMWP Observed Number of Taxa BMWP Predicted Number of Taxa (as derived from UK model)

EQIASPT = BMWP Observed ASPT (Average Score Per Taxon) BMWP Predicted ASPT (as derived from UK model) Biological Class

EQI for ASPT

EQI for Taxon

A (Very Good)

1.00 or above

0.85 or above

B (Good)

0.90-0.99

0.70-0.84

C (Fairly Good)

0.77-0.89

0.55-0.69

DC (Fair)

0.65-0.76

0.45-0.54

E (Poor)

0.50-0.64

0.30-0.44

F (Bad)

<0.50

<0.30

Table 8.01 Biological GQA class limiting criteria

Figure 8.06 Flattened mayfly nymph from the order ephemeroptera high scoring macro invertebrate indicative of good water quality

European Council Directive 92/43/EEC of the 21st of May 1992 on the Conservation of Natural Habitats and on Wild Flora and Fauna (Also known as the Habitats Directive) was enacted in Northern Ireland under the European Communities Nature Conservation (Natural Habitats etc.) Regulations (Northern Ireland) 1995.

46


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

This indicates that those areas designated as areas of nature conservation designated for salmon should strive to achieve the water quality targets that are necessary for the designated species, which has additions to the GQA standards. While it is current government policy for all rivers to meet the General Quality Assessment Standards, the Agency feels that favourable conditions standards as detailed below should be the water quality targets for all salmonid rivers within its jurisdiction.

8.1

Favourable condition tables, target levels

Natural Heritage of Northern Ireland Environment Agency have suggested guidelines for the determination of water quality, the first being the proposed UK Guidance on Conservation Objectives from monitoring designated sites and includes the following, which are considered as the favourable conditions tables. They recommend Biological GQA Class A or B with no drop in class from the existing station, and Chemical GQA Class A or B depending on which type. This is in addition to no drop in class from the existing station. In addition to these favourable conditions tables, based on publications from Conserving Natura 2000 Rivers, the European Life Series, Ecology Series; No 7 Ecology of the Atlantic Salmon, Salmo Salar L. these publications have indicated that there are specific favourable conditions for this species. An annual mean of less than 10 milligrams per litre suspended solids for nursery grounds, and annual mean of less than 25 milligrams per litre for migratory passage and the setting of soluble reactive phosphorous targets in relation to river reach types which should be as near background levels. Parameter BOD mg/l

Level 2.5

Percentile 90

Reason GQA class A

Ammonia mg/l Dissolved Oxygen % Saturation Unionised Ammonia mg/l

0.25

90

GQA class A

80

10

0.025

95

GQA class A Favourable Conditions Habitat Forming Specific for Atlantic Salmon

10 25 Background

-

Suspended solids mg/l Nursery grounds Migratory passage Soluble Reactive Phosphorous mg/l

Specific for Atlantic Salmon

Table 8.1 Favourable condition targets for Atlantic salmon

47


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

The Water Quality data in the reports has come from the Northern Ireland Environment Agency, Water Management Units Water Quality Archive. It is accepted by the Agency that monitoring is designed to ensure that water quality is monitored to ensure compliance with European Union directives. The monitoring however does not tie in well with the habitat and electrofishing survey monitoring carried out by the Loughs Agency, and as such the Loughs Agency instigated its own monitoring programmes in 2007 to link fish life, macro invertebrates and water quality into one holistic site evaluation. Additionally Northern Ireland Environment Agency, Water Management Unit data is not released in real-time and the data displayed below is for 2007, where the Loughs Agency status report is for 2008. By collecting and analysing water quality data the Loughs Agency can react to local water quality issues more effectively. From 2008 water quality information from NIEA will be reported in a different manner. The European Union Water Framework Directive requires that numerous water quality parameters in addition to those traditionally monitored should be combined to provide an overall classification for water bodies. Additional parameters will include fish, diatoms and morphology amongst others. The Loughs Agency will monitor fish for WFD purposes and provide this information to NIEA. The Loughs Agency will report on WFD classifications in the 2009 catchment status reports.

48


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Chemical GQA Very Good Good Fairly Good Fair Poor Bad 0

Drumragh Chemical Water Quality 2007

0.5

1

1.5

2 Kilometers

© Crown Copyright and database rights EMOUU205.1 © Northern Ireland Environment Agency Copyright 2007

±

Fig 8.1 Chemical General Quality Assessment (GQA) Drumragh catchment 2007. Data supplied by NIEA

49


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

Biological GQA Very Good Good Fairly Good Fair Poor Bad 0

Drumragh Biological Water Quality 2007

0.5

1

1.5

2 Kilometers

© Crown Copyright and database rights EMOUU205.1 © Northern Ireland Environment Agency Copyright 2007

±

Fig 8.11 Biological General Quality Assessment (GQA) Drumragh catchment 2007. Data supplied by NIEA

50


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 catchment 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

25

41

15

123

2003

30

48

9

128

2004 2005 2006

48

67

8

103

40

127

10

186

21

58

0

259

2007 2008

48

127

22

247

34

209

18

153

Table 9.0. Breakdown of conservation and protection duties in the Drumragh catchment 2002-2008

Year

2008

2007

2006

2005

2004

2003

Nets

111

100

97

114

181

198

Salmon

46

56

91

118

130

155

Rod & Reel

139

85

26

10

16

12

Vehicles

1

0

2

1

1

0

Table 9.01 Seized nets, salmon, rod/reels and vehicles in the Foyle system 2003-2008

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

Table 9.02 Seizures in the Drumragh catchment 2006-2008

51


DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 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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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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.

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

• •

•

• • • •

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 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 River is 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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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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 2008 In 2008 Fishery Officers Rodney Collins, Donal Lynch and Mark Mimnagh continued to work within the Drumragh catchment. Their report follows.

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

14.1

Fishery Officers Report

Regular anti lamping/poaching patrols were undertaken with private river watchers from the local angling club to protect spawning salmon and spawning sites from illegal activities. Regular routine patrols of the catchment were undertaken to detect and prevent pollution, illegal fishing activities and other activities that could impact upon aquatic habitats e.g. gravel removal, obstructions to migration, monitoring of site works and consented discharges. One statutory sample was taken in the Drumragh catchment in 2008. Routine water quality monitoring was conducted during the summer, signage was erected to notify landowners of the need for consent to remove gravel from rivers, the annual electrofishing survey was completed by September and routine patrols were carried out on a regular basis. The main angling effort within the Drumragh catchment was concentrated during September and October. No illegal angling activity was detected within the Drumragh catchment in 2008.

15.0 ACTIONS FOR 2009 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 catchment 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 associations will continue to be consulted regarding any proposed works and stakeholder input sought.

15.1

Foyle and Carlingford Areas Ongoing Actions for 2009

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. 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

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

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.

15.2

Drumragh Catchment Potential Habitat Improvement Schemes for 2009

•

Considerable scope for habitat improvement works within the Drumragh catchment exists and will be investigated in 2009

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DRUMRAGH RIVER AND TRIBUTARIES CATCHMENT STATUS REPORT 2008

15.3

Drumragh Catchment Specific Actions for 2009

•

Implement habitat improvement schemes as dictated by business plan/corporate plan

•

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

•

Assist with Water Framework Directive fish monitoring programme

•

Ensure all fish passes, dams and mill races meet required standards

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