The Tawe Salmon Action Plan TABLE OF CONTENTS 1. INTRODUCTION .......................................................................................................................... 2 2. BACKGROUND ............................................................................................................................ 2 3. CURRENT ACTIVITIES................................................................................................................ 5 4. ASSESSMENT OF STOCK PERFORMANCE ............................................................................. 8 5. PUBLIC CONSULTATION............................................................................................................ 9 6. ACTION PLAN SUMMARY TABLE ............................................................................................ 14 7. MANAGEMENT OF THE ACTION PLAN ................................................................................... 17 8. REFERENCES ........................................................................................................................... 17 i The Tawe Salmon Action Plan 1. INTRODUCTION The National Salmon Strategy, launched by the National Rivers Authority in February 1996 and inherited by the Environment Agency (NRA, 1996) sets out four objectives for the management of salmon fisheries in England and Wales: 1) Optimise the number of salmon returning to home water fisheries. 2) Maintain and improve fitness and diversity of salmon stocks. 3) Optimise the total economic value of surplus stocks. 4) Ensure beneficiaries meet necessary costs. These objectives are designed to preserve fish stocks for the future whilst protecting sustainable exploitation and recognising the economic value of the fisheries. A basic principle of the Strategy is that it will be delivered locally following consultation with local interest groups. Consequently, Salmon Action Plans (SAPs) will be produced for each of the “principal salmon rivers” in England and Wales by the year 2002. On the Tawe this process started during 2001 with the production of the Tawe SAP Consultation Document. The Tawe SAP Consultation Document: • Set a spawning target for the river • Identified the factors affecting the salmon population. • Suggested methods of addressing these limiting factors and • Invited feedback from local stakeholders and interest groups The SAP itself sets out clearly what is required to be done in the next five years or so, how it is to be achieved, who is to be involved, when it will be delivered and how much it will cost. An important element of this Action Plan is that it reflects the feedback received during consultation. Moreover, the SAP will be the means of monitoring progress and reviewing the approaches of salmon management on the Tawe. 2. BACKGROUND The Atlantic salmon has been declining throughout its range and this is believed to be largely due to cyclical factors impacting on fish during their time at sea. There is little that can be done to directly influence these factors. However, it is possible to address some of the problems facing salmon during the freshwater phase of their lifecycle. It is these latter elements that the SAP concentrates upon, with actions falling into three main categories: • Measures to increase the number of spawners by reducing legal and illegal exploitation (e.g. Byelaws) • Measures to improve environmental factors (water quality issues and sustainable land use) • Measures to improve salmon production (in stream habitat improvements and accessibility). The Tawe is a river that is recovering from an industrial heritage of heavy pollution. The improving nature of the fishery reflects this, and the river now supports a locally important salmon and sea trout (sewin) rod fishery. Sea trout are the predominant salmonid in the catchment, though a reasonable number of salmon are also present. The 2001 reported salmon rod catch of 113 from the Tawe ranked 10th out of 33 salmon rivers in Wales, and 29th out of 76 salmon rivers in England and Wales, whilst the reported sea trout catch of 373 ranked 15th out of 40 sea trout rivers in Wales and 31st out of 105 sea trout rivers in England and Wales. A map of the catchment is shown in Figure 1. 2 The Tawe Salmon Action Plan Figure 1. Tawe catchment map. h rc w T i fon n A n s y y w y w T G t n t a n H N a a f N fr d e l d s e e f i re n f G By y nt l a l N t n a 6 N Pen-y-Cae Falls h rc w T n L fo ech A Ystalyfera Ystradgynlais5 Capitol4 Falls l u e d g d U E m L p " o p w w e C r e Panteg Weir r C l C y d l e y a w d c a a h T c r h e iv R 3 Pontardawe Lower Clydach Falls 2 1 Clydach Beaufort Weir d endro t-y-F Nan Swansea ! Swansea Barrage Impassable barrier (natural) Impassable barrier (man made) Swansea Bay Partial barrier (natural) Partial barrier (man made) ! Fish pass Centres of population Rod catch data are only available for the River Tawe from 1976 onwards. During this time, the declared salmon rod catch has shown considerable annual fluctuation, though the overall trend has been upward. The five year annual catch has increased from 14.5 (1976-1980) to 81 (1997- 2001). Within the past decade, the highest recorded annual catch was 189 salmon in 1994. 3 The Tawe Salmon Action Plan Figure 2. Tawe declared salmon rod catch (1976 to 2001). 200 180 160 Rod catch 140 5 year mean 120 100 80 No. of Salmon 60 40 20 0 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 Year Sea trout constitute a considerably larger proportion of the reported annual rod catch than salmon. Reported sea trout catches were relatively high in the 1980s, but declined in the 1990s (Figure 3). The proportion of sea trout in the total annual rod catch has also fallen during this time. This indicates that factors affecting sea trout may not be influencing salmon, or if they are then not to the same extent. As well as the general decline in sea trout catches there has also been a noticeable fall in the numbers of large, multiple spawning fish returning to the Tawe. Data from Panteg trap have shown the proportion of fish returning to spawn three or more times to have fallen since the Swansea barrage impoundment (Mee et al, 1996; Scranney & McMellin, 1998; Wilson, 1999). The observed variations in catches are dependent on a range of extrinsic factors, such as river flow and fishing effort, but may also reflect cyclical variation in stock performance. The increase of catches from the 1970s to 1980s may reflect an increase in fishing effort and improvement in techniques, whilst fluctuations of catches in the late 1980s and 1990s are likely to have been influenced by successive periods of low flows which occurred during the period. Figure 3. Reported Sea Trout rod catches, 1976 to 2001. 1200 1000 Rod catch 5 year mean 800 600 400 No of sea trout sea of No 200 0 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 Year 4 The Tawe Salmon Action Plan 3. CURRENT ACTIVITIES A considerable amount of work has already been carried out to protect and improve salmon stocks within the Tawe catchment. The work carried out in recent years includes the following: • Swansea Barrage. As part of their redevelopment plans for the lower Swansea valley, the City and County of Swansea (CCS) initiated the development of an amenity barrage across the mouth of the River Tawe. In order to facilitate the passage of migratory salmonids, a ‘Pool and Traverse’ fish pass was incorporated into the barrage design. Construction commenced in 1990, and the estuary was fully impounded in 1992. The National Rivers Authority (now Environment Agency Wales) was able to undertake a limited preliminary fish tracking survey prior to impoundment, and further studies post impoundment were made possible with partial funding from CCS. A study of smolt migration past the barrage was also completed by MAFF, with assistance from the Environment Agency. Early radio-tracking studies demonstrated the fish pass to be ineffective in assisting the upstream migration of returning adults. The majority of fish entering the river were found to do so during periods of tidal ‘overtopping’. The poor performance of the pass was thought to be due to a number of factors, particularly the turbulent flow conditions within the pass. The Environment Agency requested that improvements be made to the pass, and these were completed in 2000. CCS and Swansea University are currently co-funding a 3 year study to assess the effectiveness of these improvements. This is due to report in 2003. In addition, salmonid stocks have been monitored by the Environment Agency through several methods: by trapping returning adult fish at Panteg weir and monitoring catches through an angler logbook scheme and statutory catch returns. A mark recapture study was also undertaken by the Environment Agency during the summer of 2001, with the aim of providing an estimate of the efficiency of sea trout and salmon at negotiating the fish pass. Unfortunately, a number of difficulties were encountered in capturing fish for tagging, and it proved impossible to tag sufficient fish to complete the project. The construction of the Tawe Barrage also lead to a deterioration of water quality within the impoundment (Rogers & Bryson, 1994). Only 75% of tides overtop the structure, resulting in periods of four to seven days when no saline replenishment occurs. During the summer months, particularly under low flow conditions, saline stratification within the impoundment results in a freshwater layer overlying a body of saline water, which quickly becomes depleted of dissolved oxygen (DO). Such water quality problems may influence salmonid migration of both adults and smolts. CCS have now installed a remediation scheme which has improved water quality (Edwards & Bishop, 2001). The system was completed in July 2000, and long term monitoring of the impoundment will be carried out to ensure continuing success. • Access to Spawning Habitat. Access to potential spawning tributaries is severely restricted on the Tawe by both natural and man made structures. Of the estimated 95.9km of river length within the catchment, only some 46km (47%) are accessible to migratory fish.