1 INTRODUCTION
Transcription
1 INTRODUCTION
Ythan Fishery Management Plan 2011-2015 1st Edition April 2011 (Photo: S Milne) River Ythan, Ythanbank, Ellon, Scotland 2 TABLE OF CONTENTS Section One .............................................................................................................. 6 1 INTRODUCTION ................................................................................................ 7 2 STRATEGY AND DURATION OF MANAGEMENT PLAN ........................... 8 2.1 Phase 1 Strategy .............................................................................................. 8 2.2 Plan Duration................................................................................................... 9 3 YTHAN SALMON FISHERY DISTRICT ......................................................... 9 3.1 Geology ......................................................................................................... 11 3.2 Hydrology ..................................................................................................... 11 3.3 Land Use ....................................................................................................... 12 3.3.1 Agriculture ......................................................................................... 13 3.3.2 Forestry.............................................................................................. 13 3.3.3 Natural Heritage ................................................................................. 14 4 HISTORICAL CONTEXT OF YTHAN SALMON FISHERY DISTRICT .... 15 4.1 Commercial Netting....................................................................................... 15 4.2 Angling ......................................................................................................... 17 4.3 Angling Statistics ........................................................................................... 17 4.4 Aquaculture, Still Water Fisheries and Lochs ................................................. 20 5 PRESENT STATUS OF FISH & FISHERIES ................................................. 21 5.1 Fish species present within the Ythan Salmon Fishery District ....................... 21 Table 2 Native or long established fish species known to be within the Ythan district ............................................................................................................. 21 Table 3 Fish species known to be within the Water of Cruden ......................... 22 Table 4 Non-native species known to be within the Ythan district ................... 22 5.2 Ythan Stock Components............................................................................... 22 5.3 Present Exploitation of Fish Stocks ................................................................ 22 5.4 Management Activities .................................................................................. 23 5.4.1 Stocking...................................................................................................... 23 5.4.2 Predation Control .................................................................................... 23 5.4.3 Habitat Enhancement & Obstacle Removal ............................................. 24 5.4.4 Illegal Fishing ......................................................................................... 24 5.4.5 Stock Monitoring .................................................................................... 24 5.4.6 Education and Public Participation .......................................................... 24 6 ASSESSMENT OF FACTORS LIMITING JUVENILE PRODUCTION AND FISHERY PERFORMANCE ............................................................................... 25 6.1 Habitat ........................................................................................................... 25 6.1.1 Agriculture .............................................................................................. 25 6.2 Fish Access .................................................................................................... 26 6.3 Angling and Netting Exploitation .................................................................. 27 6.4 Water Quality ................................................................................................ 27 6.5 Predation ....................................................................................................... 28 6.6 Non-Native Invasive Species ......................................................................... 28 6.6.1 Non-Native Fish Species ......................................................................... 28 6.6.2 American Mink ....................................................................................... 29 6.6.3 North American Signal Crayfish ............................................................. 30 6.6.4 Invasive Non-Native Plants ..................................................................... 30 6.7 Illegal Fishing ................................................................................................ 31 6.8 Red Vent Syndrome ....................................................................................... 31 6.9 Marine Mortality ........................................................................................... 31 3 7 INSUFFICIENT DATA ..................................................................................... 32 7.1 Genetic Status of Local Salmon, Sea trout and Brown trout Stocks. ............... 32 7.2 Numbers of Returning Adult Salmon and Sea trout ........................................ 32 7.3 Status & Distribution of Salmon, Sea trout and Brown trout Stocks ............... 32 7.4 Exploitation Rates of Salmon and Sea trout Stocks ........................................ 33 8 DEFORESTATION AND CULTURAL OLIGOTROPHICATION ............... 33 9 CLIMATE CHANGE......................................................................................... 33 Section Two............................................................................................................ 36 10 YTHAN SALMON FISHERY DISTRICT ACTION PLAN AND OBJECTIVES ....................................................................................................... 37 10.1 Objective I – Habitat Survey ........................................................................ 37 10.1.1 Survey Method ...................................................................................... 38 10.1.2 Habitat Survey – Outcomes ................................................................... 39 10.1.3 Future Work .......................................................................................... 39 10.2 Objective II – Biosecurity Plan .................................................................... 40 10.3 Objective III – Electro-fishing Survey.......................................................... 41 10.3.1 Survey Method ...................................................................................... 41 10.3.2 Electro-fishing Survey – Outcomes ....................................................... 41 10.3.3 Future Work .......................................................................................... 42 10.4 Objective IV – Structure of Ythan Fish Stocks ............................................. 42 10.4.1 Genetics ................................................................................................ 42 10.4.2 Genetics Survey Method ....................................................................... 42 10.4.3 Future Genetic Work ............................................................................. 43 10.4.4 Catch Returns and Scale Analysis ......................................................... 43 10.4.4.1 Survey Purpose .................................................................................. 43 10.4.4.2 Survey Method ................................................................................... 43 10.4.4.3 Structure Analysis – Outcomes ........................................................... 43 10.5 Objective V – Evaluate Current Restocking Programme .............................. 44 10.5.1 Survey Method ...................................................................................... 44 10.5.2 Habitat Units and Carrying Capacities ................................................... 44 10.5.3 Electro-fishing and Juvenile Densities ................................................... 44 10.5.4 Genetic Analysis ................................................................................... 45 10.5.5 Future Work .......................................................................................... 45 10.5.6 Retocking Evaluation – Outcomes......................................................... 45 10.6 Objective VI- Review the survey data gathered to understand the factors affecting the fish populations and prioritise remedies against the detrimental impacts ................................................................................................................ 45 10.7 Objective VII - Commence restoration of the district and continue to refine knowledge through continued research ................................................................ 46 10.8 Objective VIII - Review success of initial restoration schemes and prioritise works for the next five year period ...................................................................... 46 Figure 2.0 Proposed Timescale for Projects ......................................................... 47 10.9 Continued Management by YDSFB ............................................................. 48 10.9.1 Bailiffing .............................................................................................. 48 10.9.2 Biosecurity............................................................................................ 48 10.9.3 Statutory Consultee ............................................................................... 48 11. REVIEW OF THE FISHERY MANAGEMENT PLAN .............................. 48 12. REFERENCES ................................................................................................ 50 13. ACKNOWLEDGEMENTS ............................................................................. 52 14. GLOSSARY ..................................................................................................... 53 4 15. APPENDICES ................................................................................................. 54 Appendix 1- YTHAN VOLUNTARY CODE 2011 SEASON ............................. 54 Appendix 2 - DATA EXTRACTED FROM THE YTHAN PROJECT ................ 55 5 Section One 6 1 INTRODUCTION To help provide direction for the future management of the Ythan Salmon Fishery District (YSFD) and to help manage the local fisheries in a more broad and structured manner, the River Ythan Trust (SC041269)* commissioned the Deveron Bogie and Isla Rivers Charitable Trust (SC032131) to write an Ythan Fishery Management Plan (YFMP). The plan has been formulated in consultation with the Ythan District Salmon Fishery Board (YDSFB)**, Rivers and Fisheries Trusts of Scotland (RAFTS)*** and other stakeholders. The YFMP has been composed using existing information held in the River Ythan Trust data inventory, such as the 1996 Survey of Atlantic Salmon and Brown Trout Populations of Selected Tributaries within the River Ythan Catchment (Isla Martin & The Scottish Conservation Projects Trust), “Ythan Project” (LIFE00 ENV/UK/000894) and other sources, of which this document is a summary. (*The River Ythan Trust is a Registered Scottish Charity, approved in February 2010 (Registration number: SC041269) which works in tandem with the YDSFB on the management of the Ythan Fisheries District. The Trust’s mission statement: The River Ythan Trust will promote effective management to protect and enhance the fish, fishery, aquatic and riparian habitat, indigenous wildlife, and the natural environment of the River Ythan Catchment area. The Trust's objectives are: · To advance for charitable purposes and public benefit, environmental protection and improvement, by conserving and enhancing all species of freshwater fish and their environments, primarily, but not limited to the inland and coastal waters of the River Ythan Catchment area. · To advance for charitable purposes and public benefit, the education of the public and any association, company, local authority, administrative or governmental agency or public body or representative body in: The understanding of aquatic ecosystems, including their fauna, flora and economic or social activity, and river Catchment management. The need for, and benefits of, protection, conservation, rehabilitation and improvement of aquatic and riparian environments. (**Currently Scotland has 49 constituted District Salmon Fishery Boards (DSFBs), the River Ythan District Salmon Fishery Board (YDSFB) is one of these. Our adjacent Boards are the Deveron, Ugie and Don. . The YDSFB is a statutory body originated by the Salmon Fisheries Act of the 19th century and has management responsibility within the area encompassed within the boundary shown on Fig. 1.1 and the coastal area, between Newtyle in the south and and Longhaven in the north.) (*** Rivers and Fisheries Trust of Scotland (RAFTS) is the Association of Scottish River &Fishery Management Trusts. It is an Unincorporated Association registered as 7 a Scottish Charity. It operates for the benefit of its membership. A primary function of RAFTS is to fundraise on behalf of its members.) Monitoring and protection of the natural environment in Scotland is driven legislatively by the Water Framework Directive (WFD) http://www.sepa.org.uk/water/water_publications/water_framework_directive.aspx The Scottish Environment Protection Agency (SEPA) is the charged with implementing the requirements and regulations associated with the WFD. The YFMP will fit into this process by feeding information on the YSFD into the River Basin Management Plan (RBMP) http://www.sepa.org.uk/water/river_basin_planning.aspx and North East Scotland Area Management Plan via the Area Advisory Group, coordinated by SEPA. http://www.sepa.org.uk/water/river_basin_planning/area_advisory_groups/north_east _scotland.aspx 2 STRATEGY AND DURATION OF MANAGEMENT PLAN 2.1 Phase 1 Strategy „To systematically collect data on all fish species and their habitats to establish the current status of the fisheries in the Ythan Salmon Fishery District The survey programme will systematically collect data, determining: • The nature and quality of instream and riparian habitat present in the district. • Which fish species are currently present in the district. • Their distributions across the catchments. • The numbers in which they are present. • The population structure: are there bottlenecks during production reducing the number of adult fish available? Are there sub-species using different parts of the catchment? • The factors which are impacting upon the fish and fisheries. • Measures which can be taken to redress these impacts. • The effect of the rod and net fisheries on the numbers of adults of each stock escaping to spawn. • The quality and quantity of juvenile salmonid habitat As a consequence of the survey programme, management decisions will be taken based upon current information and restoration measures prioritised according to urgency and benefit. Data collected regarding habitat and obstructions will be reported to SEPA, to be included in the North East Scotland Area Management Plan and River Basin Management Plan. 8 2.2 Plan Duration The YFMP is for the period 2011-2015 and initially sets out a survey programme. As data is gathered and management decisions taken the second phase of the plan will be developed. The YFMP is designed to link together with other existing management plans previously mentioned, the North East Scotland Local Biodiversity Action Plan, as well as species specific conservation projects such as the North East Scotland Water vole Project, with the aim to address issues involving all stakeholders and prioritise actions to reduce adverse impacts. 3 YTHAN SALMON FISHERY DISTRICT The River Ythan is a long established angling river and particularly so for its prized sea trout (Salmo trutta). The fisheries in the YSFD (Fig 1.1) comprises the river Ythan and its tributaries, Ythan estuary and all other watercourses which discharge into the North Sea on Aberdeenshire's north east coast, between Newtyle and Longhaven. The main coastal river is namely the Water of Cruden. There are also four main lochs in the district namely, Meikle loch, Little loch, Cotehill loch and Sand loch, all are designated parts of the “Sands of Forvie, Ythan Estuary and Meikle Loch Special Protection Area”. (SPA) The river Ythan (Fig 1.2) rises in the Wells of Ythan (280m), flowing east to Bruckhills then north east to Towie, through Fyvie and continues south to the North Sea via Ellon, exiting at Newburgh Bar which is 20 kilometres north of Aberdeen. The river is 64 kilometers long, of which approximately 9 kilometers are tidal, with a catchment area of 680 Km² most of which is agricultural land. The Water of Cruden flows through Hatton and enters the North Sea at Cruden bay. In 1979 the Ythan Estuary was incorporated into Forvie National Nature Reserve (created in 1959). The Estuary area comprises some 976 hectares of sand dunes (the 5th largest system in Britain), tidal mud flats and water. Habitats for large numbers of birds (225 species) including: Ducks, waders, sea birds and geese as well as numerous plant species, butterflies, moths and spiders and marine life. The Estuary is designated a Special Protection Area, Special Area of Conservation, Biogenic reserve, Ramsar site, National Nature Reserve, Nature Conservation Review site, Geological Conservation Review site, Site of Interest to Natural Science and Site of Special Scientific Interest. 9 Fig 1.1 Ythan Salmon Fishery District Fig 1.2 Ythan River Catchment 10 3.1 Geology The geological structure of the Ythan catchment consists of the Lower Dalradian metamorphic rock, which is penetrated by both acid and basic igneous intrusions and, in one area, overlain by sedimentary rock. The Dalradian rock was laid down as sediments in a shallow sea or ocean shelf and is divided into bands running in a north-south direction. The most easterly is gneiss, a banded rock of fine grain material. Moving westwards the next band is quartzite. Under the pressures of regional metamorphism, grains of sand have been recrystallised to form a rock with no trace of cementation. Schists tend to have a coarser grain structure than phylites, which form the fourth and final metamorphic band within the catchment. This metamorphic basement has been penetrated in many places in north-east Scotland by granite plutons and some of these underlie Pitmedden, Birness and other areas within the catchment. The Buchan district has also been intruded by several silllike masses of basic gabbros. Some of these are of considerable size but the Schivas mass is the largest one in the catchment and a good exposure is visible at Wood of Schivas. Gabbro magmas were slow to cool and therefore formed coarse grained versions of volcanic basalts, being low in silica and high in magnesium and calcium. From Aberdour in the north a large area of old sandstone overlies the metamorphic assemblages and is mostly in the form of conglomerate. The lower section of this intrudes into the catchment as far as Fyvie and is bounded on its western edge by a series of minor faults. Following the retreat of the glaciers, the whole of the north east of Scotland was covered by boulder clay and moranic drift. In the flatter coastal regions this can reach great depths. The clays give a poorly draining soil and the number of boulders present is indicated by the massive stone dykes around the fields. From Methlick down to Ythanbank and North West of Newburgh are areas of sand and gravel of fluvoglacial origin, which offer better drainage characteristics. Alluviums are deposited along the river channels (NERPB, 1994). 3.2 Hydrology Much of the bedrock underlying the Ythan catchment is impermeable and, as a consequence, the area is generally lacking in exploitable groundwater resources. However, the aquifer formed by Old Red Sandstone deposits lying to the east of Turriff extends into the Ythan catchment as far south as Auchterless and Fyvie. This represents a potential source of supply as yet untapped in the Ythan catchment. A borehole in this same aquifer at Delgaty in the Deveron catchment yields 1Ml/d (million litres per day) for public supply (NERPB, 1994). 11 Virtually the whole of the Ythan catchment is overlain with glacial material deposited during and after the last ice age. A matrix of sand, silt and clay has been left by the ice sheet itself whilst glacial melt-water has produced large deposits of sand and gravel. Groundwater exists in these superficial deposits in useful but limited quantities. Many households throughout the catchment depend on local springs and wells for their domestic water supply. Due to the general shallow nature of the groundwater, these supplies may diminish in periods of prolonged drought. Also, because this groundwater is recharged by direct infiltration, it is highly susceptible to contamination both from diffuse pollution, such as fertilisers and slurry from agricultural land, and from point source pollution caused by nearby septic tanks and silage pits. Groundwater in the Ythan catchment makes an important contribution to stream flow. The proportion of the river or stream flow derived from stored groundwater is called the Base Flow Index and can be calculated from stream flow records. For the River Ythan at Ellon, the Base Flow Index for the ten years 1984-1993 is 0.74. This is the highest value for any gauging station in the area and one of the highest in Scotland. It indicates that, on average, just over 25% of the flow in the River Ythan is derived from direct surface runoff (NERPB, 1994). 3.3 Land Use Of the 680 km2 of the Ythan catchment approximately 90-95% is classified as agricultural. Table 1 shows the distribution of land cover within the catchment. Table 1: Land Cover in the Ythan Catchment Land Cover Group Arable Improved Pasture Coniferous Plantation Smooth Grassland Blanket Bog Built-up Land Broad-leaved Woodland Dunelands Estuary Mixed Woodland Woodland Recently Felled Low Scrub Heather Moor Salt Marsh Recently Ploughed Land for Forestry Inland Water Wetlands Total Source: NERPB, 1994. Area in % Cover km2 590.39 86.5 37.23 5.5 15.75 2.3 12.85 1.9 5.15 0.8 5.96 0.9 3.36 0.5 2.72 0.4 2.61 0.4 2.09 0.3 1.98 0.3 1.00 0.1 0.39 0.1 0.32 Not Significant 0.27 Not Significant 0.25 Not Significant 0.25 Not Significant 682.57 100.00 12 3.3.1 Agriculture Data from the June 1994 census indicated the distribution of farm types (by area) within the Ythan catchment to be as shown in Figure 1.3. Both cereal and livestock production predominate owing to the very fertile nature of the soil and the gently rolling nature of the land, which allows relatively easy soil preparation and provides a rich medium for growth. One consequence of this is rapid land drainage and nutrient loss, particularly during the winter months. The intensive nature of cereal production has led to the large-scale use of nitrate fertilisers which, in turn, has been implicated in nitrate run-off, nitrate leaching into the groundwater and the consequent indication of eutrophication problems in the estuary. Intensive livestock production, particularly in the lower part of the catchment, is a further cause of nitrate run-off arising from the resultant application of manure. It is important to highlight that farming practices within the Ythan catchment are not different from those in other river catchments. It is the high percentage of agricultural land use, coupled with a fairly small, low-land river which has lead to the relatively high nitrate concentrations. Also, it should be noted that data specific to the Ythan catchment was not readily available. Fig 1.3 Farm Types in the Ythan Catchment Farm Types by % Area 9% Cropping Mixed 1%3% 10% 43% Dairy Pig 10% 24% Cattle & Sheep Poultry Other Source: Chalmers and Crabtree, October 1999 3.3.2 Forestry In the Ythan catchment there is little tree cover as most of the land is of good agricultural quality and intensively farmed. There is some grant uptake to provide small woodland habitats for amenity and sporting use, especially where farmers are looking to take land from arable production. For example, the Grampian Forest Challenge Fund which was set up in 1996 encouraged farmers and landowners in north-east Scotland to establish well designed, productive forests, to diversify rural 13 land use and to increase timber supplies. In the first two years, 2,000 hectares of new forest were allocated funding in the north east corner of Grampian region including the Ythan catchment. (The Grampian Forest Newsletter, February 1999) The main areas of woodland plantation in the catchment are associated with the estates of Fyvie Castle, Haddo, Pitmedden, Tillycorthie, Esslemont and Auchmacoy. Elsewhere there are strips of semi-natural woodland on steeper slopes leading down to the River Ythan at Woodhead of Fyvie, downstream to Braes of Gight and Methlick. Similar slopes at Foss Braes near Tifty and adjacent to the Fordoun Burn below Rothienorman are also of lower agricultural importance and support tree cover. 3.3.3 Natural Heritage The Ythan catchment is largely agricultural and the landscape has been heavily influenced by the activities of humans. The area does, however, support a wide range of diverse habitats and species, some of which are national or internationally scarce. Forvie National Nature Reserve on the Ythan Estuary, which is also a Site of Special Scientific Interest (SSSI), is the fifth largest and least disturbed sand dune system in Britain with exceptional examples of mobile dunes and coastal heath land. A wide range of habitats is found within the Reserve and these support an equally diverse range of flora and fauna which are protected by a number of national and international designations. Other habitats of importance within the catchment have also been designated as SSSIs and include: Wartle Moss, one of the largest and least disturbed basin mires in north east Scotland; Red Moss Oldtown, a small mesotrophic basin fen, a rare habitat in north east Scotland; Meikle Loch and Kippet Hills, a eutrophic loch, which is one of the major roost sites for greylag and pinkfooted geese; and Gight Woods, one of the largest native woodlands in the Grampian lowlands. Sites of Interest to Natural Science include Gight Gorge, (entomology, ornithology, and botany) Logie Buchan Area, (entomology, reed beds and characteristic fauna) and Haddo Lakes (winter goose roost.) A number of Ythan tributaries carry a healthy population of Water vole (Arvicola amphibious.) The North East Scotland Biological Records Centre has water vole information at http://www.nesbrec.org.uk/ Information on the North East Local Biodiversity Plan can be viewed at http://www.nesbiodiversity.org.uk/worddocs/RiversBurnsHAPFINAL_Aug04.doc 14 4 HISTORICAL CONTEXT OF YTHAN SALMON FISHERY DISTRICT River Ythan and Ythan estuary fish stocks have been targeted by commercial fisheries for many years. This is highlighted below in extracts from Grimble (1899) and Calderwood (1909). “The Ythan is a famous netting river, and from 3000 to 5000 sea trout, besides salmon and grilse, are usually captured, the chief run of fish being in August and September, though the sea nets begin to get fish from the 1 st March. In the tidal water at Newburgh there are about four miles attached to the Udny Arms Hotel, where at times good sport from a boat may be had with sea trout and whitling, upwards of a hundred having once been got in a day by two rods. “ “In 1889 the Fishery Board Report states that the sea nets took 5620 salmon and grilse against thirty-seven got by the whole of the river rods; this, however, was a season of great drought, which accounts for the huge disproportion.” Augustus Grimble, The Salmon Rivers of Scotland (1899) “With regard to netting in the estuary, this has somewhat lessened in recent years. Practically only one net is fished for about two hours daily. This suits the rod fishers of the tidal waters, the fishing of which is leased in part to the Udny Arms Hotel at Newburgh. The Ythan is an excellent sea-trout river, and as this salmonid favours an estuarial habit much more than the salmon proper, the long tidal reach of the estuary forms a good rod fishery for both adult trout and finnocks. The fishing is carried on from boats, and from July to September inclusive the sea-trout are in best condition. They vary in weight from 4 ounces to about 2 Ib. and larger. Salmon are seldom fished for in the estuary, but a basket of 10 Ib. of sea-trout is considered satisfactory by those who know how to do well there”. W. L. Calderwood, The Salmon River and lochs of Scotland (1909) 4.1 Commercial Netting The practice of commercial netting within the YSFD has declined greatly and since 1997 has continued on a much smaller scale. Fig 1.4 below shows the commercial netting data from 1952-2009 15 Fig 1.4 Total Nets (Fixed Engine & Sweep net) Catch 1952-2009 Ythan Nets Catch 1952-2009 Fish Caught 16000 14000 12000 10000 8000 Salmon & Grilse Sea Trout 6000 4000 2008 2004 2000 1996 1992 1988 1984 1980 1976 1972 1968 1964 1960 1956 1952 2000 0 Year Fixed Engine Netting Stations Udny and Dudwick (owned by Udny and Dudwick Estate) – fixed engine station, which has not been operated since 1997. Lies from the mid point of the Estuary Southwards. Foveran (owned by Udny and Dudwick Estate) – fixed engine station, which has not been operated since 1997. Lies south of the of the Udny and Dudwick station. Newtyle (owned by the Crown Estates Commissioners) – this fixed engine station, not currently in operation, is the southernmost fixed engine netting station, some 3 km south of the river mouth. Crown Estate Policy is currently to leave netting stations un-let. This could change but is unlikely to in the short term. Forvie (owned by the YDSFB) – this fixed engine station, not currently in use, previously operated within an area from the mouth of the river to a point some 11 km to the north. Cruden Bay (owned by Port Errol Developments) - this fixed engine is currently in operation, working just off the harbour mouth at Cruden Bay. Longhaven (owned by Longhaven Estate) - this fixed engine station, not currently in use, is the most northerly of the 6 stations, being around 2.5 km south of Boddam. Could be operated should the owner so choose. 16 Sweep Netting River Ythan Estuary (owned by Udny and Dudwick Estate) – Sweep netting has been carried out in the past, but not in recent years. Forvie Confluence, River Ythan Estuary (owned by Auchmacoy Estate) – Sweep netting is carried out on one or two occasions per year by proprietor, not a commercial fishery. Ellon Castle – Not commercially operated at present. 4.2 Angling The legal fishings on the Ythan extend to 28 miles and support approximately 750 anglers (NERPB, 1994). The salmon and sea trout season on the River Ythan for rod and line runs from the 11th February to 31st October and for the nets from 24th February to 9th September. The catch species vary from finnock and spring salmon in early season, to sea trout in midseason, and salmon in late season. There are also some brown trout in the river although these are not significant in terms of the commercial or recreational fishery. It is very difficult to estimate an accurate figure for the value of fish in a river such as the Ythan. As a general rule, the price anglers are prepared to pay for fishing on the Ythan tends to be lower than that in other renowned Scottish rivers. In studies undertaken in the past, the annual value of rod and line fishing has been put at between £321 and £821 per fish. This allows an enormous variation but would fairly place the annual value of rod and line fishing to the local economy at least £250 000 (NERPB, 1994). A more recent study of the economic impact of angling to the Kyle of Sutherland catchment was conducted by Glasgow University. The study showed the value of angling to the Kyle catchment at £3.75million per year, furthermore providing 13% of local employment. The commercial netting of salmon and sea trout with the Ythan district has not been included in the above figures as it no longer makes a very significant contribution to the local economy. There are 5 main angling bodies within the YSFD that fish the river Ythan Fyvie Angling Association, Aberdeen and District Angling Asociation, Haddo House Angling Club, Newburgh Angling Club, Ythanbank Angling Club and 17 individual beat proprietors. Although some angling may take place on the Water of Cruden, it is insignificantthere are no sections of this river or its tributaries included in the valuation roll. 4.3 Angling Statistics Information on adult salmon and sea trout catches is available in the form of rod catch data which is compiled by Marine Scotland. The annual collection of salmon and sea trout catch data has occurred since 1952 to record the progress of fisheries throughout 17 Scotland. The data is now collected by statute under the Salmon and Freshwater Fisheries (Consolidation) (Scotland) Act 2003. Data of fish caught and returned are published in summary form in the statistical Bulletin, Fisheries Series, Marine Scotland on behalf of the Scottish Government. The total number of rod-caught salmon, grilse and sea trout (retained & released) from the Ythan district between 1952 and 2009 are shown in Fig 1.5, 1.6 and 1.7 below. Catch returns are affected by factors other than the availability of fish stocks, such as weather patterns, false recording of catches, timing of returning adults and fishing effort; but they may be used, in conjunction with other information, as an indication of fish abundance. Fig 1.5 Total rod and line (retained & released) salmon & grilse catch for the Ythan 1952-2009 Ythan Salmon & Grilse Data 1952-2009 Salmon & Grilse 1200 1000 800 Total Annual Rod & Line Catch 600 400 200 2008 2004 2000 1996 1992 1988 1984 1980 1976 1972 1968 1964 1960 1956 1952 0 Year The data above suggests a period of fluctuating catches with an overall downward trend between 1958 and 1975, which includes the outbreak period of Ulcerative Dermal Necrosis (UDN) during 1966-67, which had a destructive effect on fish stocks survival. It has been suggested that UDN was observed on sea trout from the rivers Deveron and Spey two weeks prior to it being observed on the same salmon stocks, thus suggesting that sea trout may have contributed to spreading the disease as these fish move between estuary to estuary. 1975 was followed thereafter by a period of relatively good catches with annual fluctuations until 1987. The Ythan generally relies on increases in water flows from late August onwards to draw salmon up the river – in low flow years catches are generally poor as was the case in 2003. 18 Fig 1.6 Total rod and line (retained & released) spring salmon catch for the Ythan 1952-2009 180 160 140 120 100 80 60 40 20 0 Rod-Caught Spring Salmon (Feb-Apr) 19 52 19 57 19 62 19 67 19 72 19 77 19 82 19 87 19 92 19 97 20 02 20 07 Spring Salmon Ythan Spring Salmon (Feb-Apr) Year Fig 1.6 above shows the catches of early running salmon entering the Ythan system has unfortunately declined. The decline of early running salmon has been prevalent throughout most of Scotland. The upturn shown in 1987 is thought to be a data error. Fig 1.7 Total rod and line (retained & released) sea trout catch for the Ythan 1952-2009 8000 7000 6000 5000 4000 3000 2000 1000 0 2008 2004 2000 1996 1992 1988 1984 1980 1976 1972 1968 1964 1960 1956 Total Annual Rod & Line Catch 1952 Sea trout Ythan Sea Trout Data 1952-2009 Year The data in Fig1.7 above includes sea trout caught both within the river Ythan and its estuarine fishery. Thus the data could potentially include sea trout that were destined for other north east rivers. The estuarine fishery is hugely influential with regards to the total sea trout catch of the district, with the estuary often accounting for over 60% of the total annual catch. The data in Fig1.7 suggests an increase in sea-trout catches 19 from 1952 to a peak in 1957 of 7510 fish. This was followed by a crash in numbers from 1958 to 1961. An increase in catches is shown from 1962 to 1966, but this is again followed by a crash in numbers. The reason for the decline in numbers is not known and has also been experienced in the Dee, Don and Deveron. Although not shown on the chart above, the catches on all these rivers have improved significantly for 2010. Until more recently the Scottish Government has historically asked for sea trout numbers to be classified under one main heading not taking into account their complex life histories. Sea trout which are largely female and are the migratory form of brown trout are more varied than salmon and thus its more difficult to classify their catch data. Juvenile salmon smolts around 120-160mm, after heading to sea, go far to the north Atlantic and return as adults to breed. It is thought that sea trout forage more closely inshore and many „visit‟ estuaries and fresh water before finally returning to the riverine habitat to breed. When these „visits‟ take place within months of migrating to sea as smolts, these fish are called finnock. Such fish can and have been caught in considerable numbers within the Ythan estuary. It appears from the aggregate mass of the sea trout in the Marine Scotland catch data that finnock have been arbitrarily included or not in the official returns. For example the 7,500 sea trout caught in 1957 with an average mass of 0.5Kg must have included several finnock, but it is thought that the 6,500 sea trout caught in 1966 which averaged just less than 1Kg must have been mostly sea trout (Pirie J. 2011, Personal Communication). 4.4 Aquaculture, Still Water Fisheries and Lochs The YSFD currently contains one rainbow trout fish farm and approximately four commercial trout ponds. Over the past 5 years there have also been privately owned trout ponds created by farmers through environmental schemes, some of which are believed to be stocked with rainbow trout but are not commercial and therefore we have no supplementary information. Anecdotal evidence shows that there may also be non-commercial water bodies in the district which contain coarse fish. These are listed below: Mill of Elrick Fish Farm and Fishery, Auchnagatt. Ellon NJ935408 – fully operational fish farm and fishery adjacent to the Ebrie Burn. Specialises in the raising and stocking of rainbow trout. (Oncorhynchus mykiss.) Ythan Valley Fishery, Ardlethen. Ellon. NJ920323 – Not operational at present following an outbreak of argulus. This body of water is situated very close to the Ythan mainstem, 3 miles west of Ellon. Fish species not known. Ythanbank Fishery, Ythanbank. Ellon NJ905336 – Not operational at present. There have been problems regarding water retention on-site since its conversion from a gravel pit several years ago. Located approximately 200 metres from the Ythan. Fish species not known. 20 Haddo Trout Fishery, Keithfield. near Methlick. NJ853335 -This fishery is active and is located close to the Keithfield Burn.. Stocked mainly with rainbow,, blue and brown trout, also in the past with arctic char, brook trout and tiger trout. Inverythan Fishery – NJ754415 situated at the roadside between Turriff and Fyvie. Fish species not known. Mains of Aquharney – NK022368- Pond stocked with Grass Carp not a public fishery. Meikle Loch (Slains) – NK029308 This loch is owned by the RSPB and is known to hold Pike – some angling takes place, but not encouraged by RSPB. Other fish species not known. Little Loch (Slains) – NK025311 – Fish species not known. Cotehill Loch (Collieston) – NJ027293 Shallow Loch with a maximum reported water depth of 0.25m in 1990. Known to contain three-spined stickleback and perch. Sand Loch (Collieston) – NJ034284 A report on perch in Sand Loch (Treasurer, JW, 1992. Perch in Sand Loch [Collieston, Aberdeenshire]. Unpublished report to SNH) describes finding perch, three-spined stickleback and stocked brown and rainbow trout during surveys of this loch which took place in 1975. It cites that Sand Loch was last stocked with brown and rainbow trout in 1971 and that there are no natural spawning beds in the loch. No pike were detected in this survey. Anecdotal evidence suggests pike have since been introduced to the loch. 5 PRESENT STATUS OF FISH & FISHERIES 5.1 Fish species present within the Ythan Salmon Fishery District Table 2 Native or long established fish species known to be within the Ythan district Common Name Atlantic salmon Trout (Resident / Migratory) European eel Brook lamprey Three-spined stickleback Atlantic flounder European perch Northern Pike Sand Goby Scientific Name Salmo salar Salmo trutta Anguilla anguilla Lampetra planeri Gasterosteus aculeatus Platichthys flesus Perca fluviatillis Esox lucius Bobius minutus 21 NB: The Ythan historically contained a healthy population of Freshwater Pearl Mussel (Margaritifera margaritifera) and was once a renowned pearl mussel fishery. The Ythan was intensively surveyed by ecologists from the University of Aberdeen and Germany between July 1996 and 1997. The findings showed a small population of old individuals but no sign of juvenile recruitment. On a historical note: In 1621, the Kelly (or Kellie) pearl, found in a tributary, is believed to be the largest found in Scotland, was presented by the Lord Provost of Aberdeen to King James VI, and is now part of the Scottish crown among other pearls, diamonds and rubies. Table 3 Fish species known to be within the Water of Cruden Common Name Atlantic salmon Trout (Resident / Migratory) Scientific Name Salmo salar Salmo trutta Table 4 Non-native species known to be within the Ythan district Common Name Rainbow Trout Grass Carp Scientific Name Oncorhynchus mykiss Ctenopharyngodon idella 5.2 Ythan Stock Components The Ythan system and the Water of Cruden have a diverse and complex make up of fish stock components and run-timings e.g. spring, summer and autumn salmon. Throughout the catchment there are separate and distinctive stocks of salmon, sea trout and brown trout which need to be preserved at all cost. It is this diversity of stock which gives the Ythan its 9 month long angling season. Understanding of the structuring of Atlantic salmon, sea trout and brown trout stocks within rivers is essential for focusing local management and stock assessment on breeding populations, the fundamental biological units which underpin recruitment and their character. River Ythan Trust and YDSFB understand the importance of researching and preserving distinct local populations. 5.3 Present Exploitation of Fish Stocks The angling season currently runs from the 11th February to the 31st October inclusive, the netting season from 24th February to 9th September inclusive. The YDSFB operate a voluntary angling conservation code which is reviewed before the beginning of each new angling season. A copy of the updated voluntary code can be found in Appendix 1. The exploitation of salmon and sea trout by rod and line occurs mainly on the Ythan mainstem and estuary. Some brown trout fishing is practiced on the upper reaches of the Ythan. 22 There are still two netting operations in use within the Ythan district. Cruden Bay (fixed engine) netting station is currently in operation, working just off the harbour mouth at Cruden Bay and Forvie Confluence (sweep netting station, Ythan Estuary) is operated one or two occasions per year, but not commercially. 5.4 Management Activities 5.4.1 Stocking The YDSFB operate a modest juvenile restocking programme. Both salmon and trout of known migratory parent origin have been stocked into the Ythan system intermittently and also the Water of Cruden was stocked with trout fry in 2006 due to a pollution incident. Stocking of juveniles has been carried out mainly to mitigate against serious pollution incidents which have adversely damaged salmonid stocks and their habitats. The YDSFB do not own their own hatchery facility and subsequently buy in fed fry / parr / smolts from outside commercial units. The most recent year that salmon has been stocked into the Ythan system was 2003. These fry were of Ythan parentage and were reared at a local fish farm. Trout fry and smolts for stocking purposes have been sourced from outside the district. 5.4.2 Predation Control Predation of salmon and trout stocks is a natural occurrence with other fish species, piscivorous birds and mammals having co-existed in ecological balance over millennia. Juvenile salmonids are eaten by a number of different predators including eel, kingfisher, sawbill ducks, cormorant, and mink. Adult and salmonid smolts are also preyed upon by species such as otter and seals. The predation of early life stages of salmonids may not have a huge effect as the populations can in most cases compensate for losses. However, when salmonids reach the parr and smolt stages, the population loses some of its ability to compensate for loss. During smolt migration, salmon and sea trout are particularly vulnerable to predation due to high densities and mass downstream migration. Predation can exert a significant effect upon smolt numbers. The effect of avian predation on fish stocks within the Ythan catchment is unknown, but during the smolt run and in times of low water may be significant. Recent research has shown that, across Scotland smolt survival rates have been declining. There is no formal management of piscivorous birds at present, however the YDSFB have for several years been discouraging these birds by use of non – lethal techniques (sound scaring) which they regard as having been reasonably successful. Anglers have expressed concern about the steadily increasing numbers of particularly grey seals in recent years and the possible predation on salmon and sea trout smolts and adults. The lethal control of grey and common seals is not permitted within the Ythan estuary or main river channel up to Logie Buchan Bridge. Scottish Natural Heritage who manage the National Nature Reserve (including the estuary) gave an official response to the Scottish Government when an application to control seals was made “The control of seals within the estuary is considered inappropriate by SNH who manage the NNR, due to lack of evidence of damage to the fishery and that a key attribute of the reserve is primacy of nature and promoting public awareness and enjoyment”. The YDSFB have controlled seals in the appropriate season and with the aid of the required licence in the closed season, from Logie Buchan Bridge to Methlick. Seals present in this section can be clearly identified as chasing migratory 23 salmonids. The YDSFB have recently applied for the appropriate licence to enable this practice to continue in the future. The control of American mink is currently undertaken by the North East Scotland Water vole Conservation Project, the Ythan Project Volunteers and the YDSFB superintendent. Mink numbers had been controlled by the YDSFD for many years prior to the introduction of the Watervole Conservation Project and undoubtedly contributed significantly to the survival of a water vole population in the catchment. 5.4.3 Habitat Enhancement & Obstacle Removal Habitat works within the district have mostly been carried out as part of “The Ythan Project” (LIFE00 ENV/UK/000894), which studied a wide range of environmental matters in the catchment during the period 2000-2005 and put subsequent remedial actions in place. Some of these actions included the provision of buffer strips, fish pass construction, coniferous tree removal, removal of Japanese Knotweed, habitat surveys and the creation of sea trout spawning beds. Other work has also been undertaken by the river superintendent such as debris removal from spawning burns. 5.4.4 Illegal Fishing The control of illegal fishing or „poaching‟ as it is referred to is under the control of the YDSFB. Coastal patrols are undertaken and the YDSFB also carry out river patrols for illegal activity, such as netting and fishing without permission, through the remit of the river superintendent. 5.4.5 Stock Monitoring The YDSFB has carried out an annual programme of electro fishing since 2002 to monitor juvenile stock abundance and distribution. The River Ythan Trust will expand this monitoring programme and provide advice to assist the YDSFB in managing the fisheries district in a more comprehensive and efficient way, for example, direct obstruction removal works, habitat evaluation and possibly stocking.. A number of juvenile surveys were also completed in 1996 by the Scottish Conservation Projects Trust on behalf of the YDSFB. 5.4.6 Education and Public Participation Education programmes to date have mostly been carried out as part of “The Ythan Project” (LIFE00 ENV/UK/000894). Close to 47 separate work packages were carried out as part of the project such as river information sessions completed with various local primary schools and nutrient budgeting workshops for the agricultural community. The YDSFB have also involved some local schools when stocking out fish from the hatchery programme. It is the intention of the trust (funds permitting) to develop an education project such as “Salmon in Trout in the Classroom” similar to those that have been implemented by other rivers trusts, for primary schools in the YSFD – some preliminary research has been done in establishing the contact names, e-mail details and addresses of likely schools. A number of interested anglers have offered their unpaid assistance for river 24 works. Similarly a number of anglers have undertaken instruction in the collection of scale samples for examination and record purposes. 6 ASSESSMENT OF FACTORS LIMITING JUVENILE PRODUCTION AND FISHERY PERFORMANCE 6.1 Habitat 6.1.1 Agriculture Over 90% of the Ythan river catchment is agricultural land. Watercourses within the fisheries district, devoid of livestock fencing, have suffered from resulting areas of bank collapse, which has in turn increased in stream silt loading, resulting in riverine habitat becoming degraded. Rivers with soft, alluvial soil banks are prone to chronic collapse where stock fencing is absent. A survey was completed of watercourses within the Ythan in 2004, assessing the impact of stock on bank sides. No current habitat data exists for The Water of Cruden. In 1991 the Ministry of Agriculture, Fisheries and Food looked at agricultural practices and drainage as an impact on salmon smolt production as part of a Salmon Advisory Committee report. The main findings are shown below. „Drainage of land for arable production and improved grazing has been extensively practised by providing underground pipes („land drains‟) and drainage ditches, and by the dredging of main channels to lower the water table. This has the effect of increasing the speed of run-off so that the peak flows are greater and the base-flow reduced. Both these extremes are potentially damaging for juvenile production. Input of suspended solids as a result of farm practices can render gravel unsuitable for spawning and incubation. The post-war intensification of arable farming practices has tended to increase the likelihood of serious soil erosion. For example, modern crop patterns often leave land vulnerable to erosion during the autumn and winter, when peak rainfall occurs. This results in increased soil erosion to watercourses, particularly where the land gradient is steep or where low-lying land is prone to flooding during this period. Access to the stream bank by grazing livestock can cause damage by destruction of bankside vegetation and breakdown of banks, allowing a considerable input of soil material into the water. In severe cases the banks may be destroyed, leading to considerable channel widening and shallowing and a very high input of suspended solids. Channelisation for land drainage and flood alleviation generally involves straightening and deepening the channel. This results in removal of much of the habitat diversity and in particular shallow areas important for salmon parr and much spawning gravel. Considerable damage has been done in the past, from which recovery has been slow. Publication of the „Rivers and wildlife handbook‟ by the RSPB and RSNC in 1984 was of major assistance. Bankside cover can be important to juvenile salmon in small shallow streams. Clearing of such cover, either intentionally or by allowing intensive grazing, can significantly reduce the carrying capacity. On the other hand, domination of the banks by coniferous plantations can reduce light penetration and thus primary productivity, reducing fish production. It 25 also greatly restricts the more valuable community of bankside vegetation. New drainage schemes are now less numerous and it is likely that some existing schemes, particularly in rural and upland areas, will slowly deteriorate. It is however important that the criteria for the maintenance of such capital schemes should now be reconsidered. Natural recovery from unsympathetic channelisation is slow but does occur, but improved awareness by river and estate managers should ensure that less damage is done in the future. Input of silt from arable farming can be controlled by leaving uncultivated areas (ideally several metres wide) alongside the stream and any feeder tributaries. This also satisfies the requirement for bankside cover. Further, avoiding access by cattle in intensively grazed areas (except for limited drink areas) can prevent damage to bankside vegetation and to banks themselves.‟ The adverse affects of cattle access to the water bodies could possibly be further reduced by the provision of water troughs. The Water Environment (Controlled Activities) (Scotland) Regulations 2011 came into force on 31st March 2011, these being an updated version of similar earlier documents. The document can be seen and downloaded from the SEPA website http://www.sepa.org.uk/water/water_regulation.aspx. Diffuse pollution is a significant factor in preventing the improvement of water quality in the YSFD. Some of the General Binding Rules (GBRs) contained within the regulations are designed to minimise this problem. GBR 18 The storage and application of fertiliser. GBR 19 Keeping of livestock – forbids poaching by cattle within a 5 metre distance from surface water, plus other measures. GBR 20 Cultivation of land - forbids cultivation of land within 2 metres of surface water, plus other measures. GBR 23 Application of pesticides. GBR 24 Operating sheep dipping facilities. 6.2 Fish Access Current migratory fish access within the Ythan district is thought to be reasonably unimpeded. Habitat surveys carried out as part of “The Ythan Project” (LIFE00 ENV/UK/000894) noted several possible obstructions to migratory fish in the form of bridge aprons, culverts or old weirs. A number of these obstructions have been modified by the YDSFB under or following the aforementioned project, which appear to have been successful. All other possible obstructions highlighted within the habitat surveys and outlined in appendix 2, will require to be re-visited to assess their current state. All obstructions to migratory fish tend to be historical, as any new developments must consult with the YDSFB & SEPA regarding fisheries interests. In-stream works have to be carried out in compliance with the requirements of SEPA‟s “The Water Environment (Controlled Activities) (Scotland) Regulations 2005.” http://www.sepa.org.uk/water/water_regulation.aspx A potential source of funding to deal with obstructions exists through SEPA‟s Water Environment Restoration Fund. www.sepa.org.uk/water/restoration_fund.aspx 26 6.3 Angling and Netting Exploitation Throughout the angling and netting season, potential spawning salmon, sea trout and brown trout are inevitably caught and retained. This in turn reduces the number of adults available to fully utilise their spawning habitats and produce the next generations. During the 2008 fishing season, anglers released 45% of salmon/grilse and 30% of sea trout caught within the district and netting activity recorded 127 salmon & grilse and 18 sea trout caught. During the 2009 season anglers released 51% of salmon/grilse and 38% of sea trout caught and netting activity recorded 204 salmon and grilse and 53 sea trout. Currently there is insufficient information available to determine the effects of angling and retention of salmon and sea trout on the stocks within the catchment. However all angling bodies on the Ythan, over a period of years have reduced the numbers of fish that may be retained, and more recently have adopted the policy of returning a greater proportion of fish caught. Netting activities are not thought currently to be having a significant effect on salmon and sea trout stocks within the catchment – the only operating fixed engine (Cruden Bay) is a mixed stock fishery which will probably exploit fish originating from several east coast rivers – the operating sweep netting station in the Ythan takes only a few fish and is owned by an organisation with valuable angling interests in the Ellon area. 6.4 Water Quality To survive and flourish, fish stocks, especially juvenile salmonids, require well oxygenated water of neutral acidity, free of toxic and organic pollution. Invertebrates living within rivers, the base of the aquatic food chain, providing food for salmonids, also require high quality clean water and are similarly very sensitive, even to minor changes. A number of key river shingle invertebrate species are found within the district, all of which are listed as „Priority‟ species in the UK Biodiversity Action Plan. These species are covered by a UK Grouped Action Plan which identifies a number of issues facing these species, such as agricultural pollution, removal of sediment, deepening of watercourses and water abstraction. It is clear many of these issues are relevant in the river Ythan catchment context. SEPA operates a river classification scheme to establish and monitor the status of surface water bodies. The key reasons for water bodies being at less than good status are diffuse source pollution and alterations to beds and banks (morphology). The Ythan catchment contains 11 surface water bodies, and only one (the Burn of Sessnie {Cessnie Burn} achieved good ecological status in the River Basin Management Plan (2009) more detail can be viewed on the SEPA interactive map. http://gis.sepa.org.uk/rbmp/ Unfortunately the river Ythan has some of the highest nitrate concentrations in Scotland. Several water bodies within the catchment fail to achieve what is referred to as „good ecological status‟ under the EU Water Framework Directive. The Ythan catchment and the Ythan estuary were designated as a Nitrate Vulnerable Zone (NVZ) in May 2000, based on high nitrate concentrations and extensive growths of green algae in the estuary. The area now forms part of an NVZ designated in 2002, which includes parts of Aberdeenshire, Banff, Buchan and Moray. The highest concentrations of nitrate found within the Ythan are within its groundwater. A review 27 completed by the Scottish Environment Protection Agency (SEPA) showed that agriculture is the main source of nitrogen in the catchment with some 91% of nitrogen loading being attributed to agricultural fertilizers and manure. In 2009 the Ythan was designated by SEPA as a diffuse pollution priority catchment. A „diffuse pollution priority catchment‟ is a catchment containing water bodies that don‟t meet environmental quality standards and requires a catchment-wide approach to reduce diffuse pollution risks. Further information on current status and ongoing monitoring view www.sepa.org.uk/water/diffuse_pollution/monitored_catchments.aspx Catastrophic pollution incidents occurred on some of the tributaries in the 1990s in relation to silage effluent and slurry. Similar serious incidents have not re-occurred recently, however the potential for such events have not vanished. Since 2000, and up to the current time, there have been numerous incidents involving oil, silage, slurry and silt. 6.5 Predation The numbers of piscivirous birds such as goosanders and mergansers appear to be increasingly more common within the district and along with other species such as cormorant are probably predating on juvenile salmonids at vital life stages. The abundance of American mink which also prey on juvenile salmonids should continue to decline with a catchment wide control programme now in place. Currently there is no hard scientific evidence regarding the level of predation by seals on salmon and sea trout smolts and adults and whether they have a serious impact on Ythan stocks or the sea trout stocks of adjacent rivers. . There appears to be little doubt that the numbers of grey seals are, at times within the estuary, greater than in the past – the grey seal count on 22nd April 2010 was recorded as 369. In an attempt to lessen the impact on estuary anglers and adult fish stocks, a seal scarer was obtained, mounted on a boat and operated by Udny and Dudwick Estate, Oceanlab (University of Aberdeen), Bennex, and Newburgh Anglers. Initial trials have been positive with estuary anglers being undisturbed by seals when the scarer was in operation. This experiment is to continue during the 2011 angling season. 6.6 Non-Native Invasive Species The Trust will be developing a Biosecurity Plan to address the issue of the non-native species shown below and any other similar species, in line with The Invasive NonNative Species Framework Strategy for Great Britain http://www.nonnativespecies.org 6.6.1 Non-Native Fish Species The abundance of Rainbow trout (Oncorhynchus.mykiss) caught from the Ythan catchment has increased in recent years. The presence of a rainbow trout fish farm within the district provides a potential source of escapee rainbow trout. Anglers have on occasions reported the presence of different life stages of rainbow trout in the river. As rainbow trout and salmonids have similar life histories, there is potential for interactions between these species. For example, rainbow trout are hatchery reared and have been conditioned to feed within the water column in a similar way to salmon. 28 A number of rainbow trout fisheries, both commercial and recreational, also exist. The presence of connections between still waters and the Ythan catchment allows a potential avenue by which non-native fish species, in the absence of a sluice or grid on the water‟s outflow, may enter the river catchment. During flood conditions, even those ponds with sluices or grids are likely to be ineffective and non-native fish may enter the main river system. There should be further investigation into the status of all screens present on outflows of fishery ponds which have an outflow to the main river.. The spread of viral and bacterial diseases affecting salmonids is often facilitated by high density rearing environments such as those encountered in fish farm enterprises. Farmed fish are a potential route by which disease can enter wild fish populations. In the UK, the potential for disease transfer from out with the UK is minimal due to the British trout industry not sourcing fish from the EU mainland or Norway. The Aquaculture and Freshwater Fisheries (Scotland) Act 2007 makes it an offence for any person to intentionally introduce any live fish or spawn of any fish into inland waters, or possess such with the intention of introduction without previous written agreement of the appropriate authority. http://www.scotland.gov.uk/Topics/marine/Licensing/fishintros 6.6.2 American Mink The non-native American mink (Mustela vison) is first thought to have reached Britain in 1929. It is not known when they first reached the Ythan system. The main threat they pose to fishery performance is the reduction in juvenile production through predation. The Ythan also has a breeding population of water voles (Xavier Lambin et al, 1996 and subsequent works), to which the presence of mink also pose a threat. Figure 1.8 American Mink Distribution Data (Scotland) From Figure 1 above it can be seen that the North East region is at the northern boundary for mink distribution in Scotland. Collaboration between SNH, District Fishery Boards, Trusts, North East Water Vole Conservation Project and landowners is required to contain the spread and increase of mink. 29 6.6.3 North American Signal Crayfish Signal crayfish (Pasifastacus leniusculus) have been present in Britain since they were first imported from Sweden during the 1970s. Subsequent escapes from farms and deliberate illegal releases have resulted in the establishment of new feral signal crayfish populations over large areas of England and Wales. Several records exist of signal crayfish introductions to Scotland during the 1980s and there is some anecdotal evidence to suggest that crayfish were translocated to a variety of locations at that time. They were first formally recorded in Scotland during 1995, since when a total of 15 populations have been identified. These extend from the Kirkcudbrightshire Dee in Galloway and the River Clyde in Lanarkshire to the River Nairn near Inverness. Populations have also been recorded in the catchments of some of Scotland‟s most valuable river systems, such as the Tay, Tweed and North Esk. New populations are now being reported at a frequency of two or three per year. Signal Crayfish are not in the Ythan fisheries district at present. Everything possible must be done to ensure they are stopped from entering. Signal crayfish have a significantly adverse impact on native freshwater flora and fauna in running and standing waters. They can do this by consuming large quantities of plants and invertebrates, and by either predating or displacing amphibians and fish. Signal crayfish can also modify aquatic environments, by burrowing into the banks of rivers and ponds. In ponds, this behaviour can undermine the littoral zone and result in increased turbidity. In running waters, extensive burrows may destabilize the riparian zone, leading to increased rates of bank erosion, the shallowing of streams and the compaction of salmonid and lamprey spawning grounds. The species‟ impact on freshwater pearl mussel is unknown but is likely to be significant. The potential for signal crayfish to act as a vector for transmission of diseases within or between catchments cannot be discounted. 6.6.4 Invasive Non-Native Plants Japanese knotweed The invasive-species, Japanese knotweed (Fallopia japonica) is present within the district. It is not currently a major concern but if allowed to establish further, it poses the threat of shading out native plants by producing a dense canopy of leaves early in the growing season which can accelerate bank erosion. Knotweed also offers a poor habitat for native insects, birds and mammals. Any existing populations should be treated immediately before spreading further. Giant hogweed The non-native species Giant hogweed (Heracleum mantegazzianum) is also present within the district but not on a large scale. Giant hogweed dominates vegetation in marginal habitats and along rivers, thus crowding out native plants and leaving river banks open to erosion. Sap from the plant also poses a threat to human health. It is important that the present abundance of this species is surveyed and updated to allow control work to be undertaken as soon as possible. 30 Himalayan balsam Himalayan balsam (Impatiens glanulifera) has been reported within the district (Water of Cruden only). Himalayan balsam shades out native grasses and leaves banks prone to erosion. Similar to many invasive species it is important to control the spread as soon as possible. Himalayan knotweed Himalayan knotweed (Percicaria wallichi) has also been found within the district. Himalayan knotweed again shades out native grasses and leaves river banks prone to erosion. Similar to many invasive species it is important to control the spread as soon as possible. 6.7 Illegal Fishing Salmon „poaching‟ is not a serious problem within the YDSFB management area but does sporadically occur. Episodic occurrences of illegal activity such as netting or fishing without permission potentially reduce the numbers of spawners available. 6.8 Red Vent Syndrome The issue of RVS is an emerging one. RVS has been present with Ythan salmon stocks with recent years. Parasitological investigations carried out by Marine Scotland have discovered the presence of nematode worms (Anisakis sp. and Hysterothylacium sp.) in the region of the vent of all fish examined that showed signs of RVS. These parasites can occur naturally in wild fish and are a contributory factor, or may be the primary cause of RVS, but this is still under investigation. At present the two main threats that RVS pose are, the possible hindrance of adult salmon spawning and the threat to human health if guidelines are not followed when preparing wild salmon. 6.9 Marine Mortality The increasing quandary of marine mortality in post-smolts is out-with the scope of this management plan. It is arguably the most significant current problem affecting adult production and fishery performance today. The marine survival of post-smolts leaving Scottish rivers has declined in recent years. Monitoring undertaken in the past by Fisheries Research Services (FRS) suggests that the marine survival of smolts leaving the River North Esk declined from an average of 15% in the 1980s to 8% in the 1990s. This is largely due to climatic changes in the North Atlantic (Anon., 2001). This has resulted in fewer adults returning to the Ythan. The spring-running stock of older sea-age fish has been worst affected. The activities of the former FRS are now undertaken by Marine Scotland Science. (MSS) 31 7 INSUFFICIENT DATA At present there are subjects that the YDSFB and River Ythan Trust have insufficient data to aid in making more detailed and informed decisions in the management of the local fisheries. The areas that require further data collection are summarised below. 7.1 Genetic Status of Local Salmon, Sea trout and Brown trout Stocks. The YDSFB hold no genetic data at present. A full mapping programme to determine the genetically distinct salmon populations of the system is desirable. The use of genetic analysis as a management tool could significantly help the effectiveness of local management actions, by for example allowing the categorisation of juvenile electro-fishing data into spring, summer and autumn juveniles and/or by helping to steer and assess the effectiveness of the restocking programme, along with many other possibilities. 7.2 Numbers of Returning Adult Salmon and Sea trout At present the YDSFB have no existing adult fish counting facilities. To bring together the planned research on stock component distribution (genetic sampling) and age structure analysis (scale sampling), the River Ythan Trust plan to research into whether there are enough adult fish of each stock component escaping the pressures on them to fully seed their nursery habitats. This research would determine if spawning targets or predicted „Conservation Limits‟ are being met., The installation of fish-counters could greatly assist in this research, ideally done on a stock by stock basis i.e. if genetic /scale analysis concludes that a significant proportion of spring salmon utilise the upper Ythan, a counter would be installed at an appropriate place in this location. The three main counters most commonly used for counting adult salmon are resistivity, optical and hydro acoustic. Both resistivity and optical counters are most commonly sited in fish ladders or on in-river structures like weirs. Hydro acoustic counters do not require a permanent structure which would initially make them more appealing. Unfortunately recent research has shown that if hydro-acoustic counters are not sited correctly, their counting capability is severely compromised. 7.3 Status & Distribution of Salmon, Sea trout and Brown trout Stocks Data collection by the YDSFB has historically concentrated on salmon and trout stocks. The main method deployed to gain juvenile information has been electrofishing, and for adults, analysis of catch records. At present because there is not an adequate sampling technique available for juvenile salmon, contained in larger watercourses the data we hold in these areas are minimal. This is particularly significant in the case of the main Ythan Channel which has a low number of spawning tributaries, which would normally be targeted for electro-fishing monitoring. The YDSFB holds no spawning location data for individual stock components for example summer sea trout or spring salmon. First and foremost for 32 future research is to establish spawning locations of all components. Through the aid of genetic analysis this could be achieved. 7.4 Exploitation Rates of Salmon and Sea trout Stocks Currently there is no existing data on exploitation rates of returning adult salmonids. To assess the pressure of the rod and line fishery on sub-components such as autumn salmon or sea trout requires a tagging and recapture programme to be developed. The planned programme would require adult salmon to be captured as close to the Ythan estuary as possible, thus allowing for them to be tagged and released back into the river system. The number of tagged fish later recaptured by anglers would then be monitored to establish an exploitation rate. 8 DEFORESTATION AND CULTURAL OLIGOTROPHICATION The loss of riparian woodland is a characteristic of the upper catchments of many rivers in the region. The Ythan district has not been affected to the same level as neighbouring districts but deforestation has occurred to a lesser degree. This was largely caused by the clearance of native woodland for grazing in the 19th century and has been maintained by grazing pressure by deer and sheep since. The consequences of this loss of riparian woodland have been; · A loss of biodiversity within and at the margins of waterways. · Increased erosion of river banks leading to siltation and degradation of rivers · A loss of buffer habitat which filtered and slowed down water flow from surrounding land. This increases pollution and flood risk. · Increase in summer water temperatures because of lack of shading. · Reduction in nutrient status of rivers because of lack of leaves and invertebrates from the riparian zone. · Fragmentation of habitat and the loss of the natural corridor which connected habitats and species. It should be noted that around 2250 trees have been planted on the banks of the Ythan and tributaries between 2002 and 2004 which is a higher rate of riparian woodland creation than would happen naturally. 9 CLIMATE CHANGE A Scotland and Northern Ireland Forum for Environmental Research (SNIFFER) 2006 publication „A Handbook of Climate Trends across Scotland‟ examined climate trends in the last century. These trends predict impacts on the freshwater environment which are summarised in the SNIFFER report and are shown below. The predicted changes outlined would inevitably have consequences for the Ythan fisheries district. There is likely to be more variation in marine survival, run timing and condition of salmon / sea trout. There are likely to be more frequent and damaging extremes of flow and temperature. Changing conditions may also favour some non salmonid species. A safe and stable hatchery incubation environment and stocking policy may provide some mitigation for winter flooding and redd washout. It may be necessary to 33 develop more sustainable land use practices and revert to a more naturalised environment. (Extract below taken from: Scotland and Northern Ireland Forum for Environmental Research. 2006. Handbook of Climate Trends across Scotland.) 34 35 Section Two 36 10 YTHAN SALMON FISHERY DISTRICT ACTION PLAN AND OBJECTIVES The principal strategy of this management plan is to establish a framework to systematically collect data on all fish species and their habitats to establish the current status of the fisheries within the Ythan Salmon Fishery District. (YSFD) In order to achieve this, a number of objectives have been set out below; Objective I Establish a comprehensive habitat survey of the YSFD. Objective II Establish a biosecurity plan for the YSFD. Objective III Complete baseline electro fishing surveys of the YSFD. Objective IV Research the current structure of fish stocks in the YSFD. Objective V Evaluate current restocking programme. Objective VI Review the survey data gathered to understand the factors affecting the fish populations and prioritise remedies against the detrimental impacts. Objective VII Commence restoration of the fisheries within the YSFD and continue to refine knowledge through continued research. Objective VIII Review success of initial restoration schemes and prioritise works for the next five year period. 10.1 Objective I – Habitat Survey A comprehensive habitat survey is an important first step to understanding the YSFD and its localised problems. Previous habitat surveys carried out as part of “The Ythan Project” (LIFE00 ENV/UK/000894) during 2002-2004 were extremely beneficial to the YDSFB in determining e.g. possible obstructions to migratory fish. Mapping the location, quality and suitability of the habitat for juvenile fish production and then comparing it with the actual usage, from electro-fishing surveys, will highlight good areas being under-utilised as well as areas where poor quality habitat is restricting fish production. 37 Data collected in the habitat survey will feed into many of the other avenues of investigation on the catchment and so its completion should be priority. It can be expected from the analysis of diffuse pollution already carried out on the Ythan as part of the Water Framework Directive (SEPA, 2008) that there are likely to be watercourses which would benefit from measures to reduce the impact of agricultural pressures. By carrying out a catchment-wide habitat survey the options for habitat improvements, for example reducing in stream siltation, can be prioritised to where they will be of most benefit. 10.1.1 Survey Method Initial efforts will be directed at habitat suitability for salmonids, as they form the main Ythan fishery. Habitat features significant to other species will be noted at the same time, for example suitable nursery areas for lamprey or gravel areas where freshwater pearl mussels may be present, and targeted for specific study projects at a later date. The Ythan catchment should be covered primarily and the Water of Cruden catchment thereafter. To cover the Ythan catchment efficiently the walkover survey method of Hendry and Cragg-Hine (1997) described in the SFCC‟s Habitat Surveys Training Manual (2007) is recommended. This is targeted towards salmonids and provides a means of recording on a map the location of instream habitat types suitable for different ages of fish and features of significance about the surrounding riparian zone, for example the condition of the banks, presence of pollution sources and obstructions to migration. It is suggested that the aforementioned survey work be carried out in the months of May to September. . The survey methodology recommends a team of two surveyors which cover the river in a leapfrog manner surveying alternate stretches and moving transportation forward to a prearranged site each time a stretch is completed, thereby, whenever road access allows, avoiding the need to double back at the end of the day to return to the vehicle. In addition to covering the ground most efficiently, this team coverage can also be used to record suitable locations for the later electro-fishing survey. Ideally the survey should be completed within one season, however, due to limited resources the River Ythan Trust expects that this exercise is likely to span two seasons. Plant species will be considered, including invasive species such as Giant hogweed and Japanese knotweed etc. which have been noted previously. Since it is not expected that the habitat surveys can be completed in a single year, electro-fishing surveys should generally be postponed until they are. Electric fishing carried out in the first year should be restricted to the possible collection of some genetic samples and impact assessments of known or suspected obstructions. The data produced can be analysed internally by the River Ythan Trust and also can be incorporated into a Geographical Information System (GIS) to aid interpretation with other data sources across the catchment by other bodies if required. Data gathered as part of the earlier habitat survey can be compared with current data to determine if areas have further deteriorated or even improved. 38 10.1.2 Habitat Survey – Outcomes Location and extent of obstructions to migratory fish Presence of invasive plants Presence of degraded riparian habitat Location, extent and quality of salmonid spawning grounds Location, extent and quality of salmonid nursery grounds Location of pollution sources Location of likely habitat for possible future lamprey and freshwater pearl mussel studies. 10.1.3 Future Work Areas of the catchment identified for improvement works, whether instream works, such as rubble mat addition, or riparian works, such as fencing and buffer strip creation or tree planting, can be prioritised when the habitat survey has been considered in conjunction with electric fishing and other data. This should be based on factors such as those considered in the River Dee Trust‟s 2008 report “Prioritisation of Habitat Restoration based upon the 1999 River Dee Habitat Survey and Subsequent Updates”: Feasibility of the restoration work Severity of the impact Potential increase in fish production following restoration Impact on vulnerable components of the fish stock e.g. spring salmon Cost of implementing restoration work. Once work has been prioritised detailed surveys of the tributaries in question can be carried out to produce project plans fully costed to the type of improvements required. SEPA‟s Water Environment Restoration Fund may be a source of funding for habitat restoration work. http://www.sepa.org.uk/water/restoration_fund.aspx Application can be made to the Scotland Rural Development Programme for assistance, and consultation with the local landowners, to ensure their needs are met. Future revisions of the Fishery Management Plan for the river will encompass these plans and the subsequent monitoring, to quantify their success. 39 10.2 Objective II – Biosecurity Plan To develop a Biosecurity Plan to address the issue of non-native species and any other similar species, in line with the Invasive Non-Native Species Framework Strategy for Great Britain. http://www.nonnativespecies.org This plan will describe the biosecurity issues of the YSFD and present the actions that will be agreed with relevant stakeholders for the prevention, early detection, control and mitigation of the introduction and spread of selected invasive non-native species (INNS), fish diseases and parasites. The vision of the plan will be: „To establish a sustainable framework this will prevent, detect, control and eradicate invasive non-native species within the YSFD through appropriate management, data collection, liaison and education‟ The vision will be achieved through the realisation of three objectives: Prevent the introduction and spread of INN species within the YSFD. Develop optimum detection and surveillance of, and rapid response to, new INN species. Develop effective control and eradication programmes for INN species which are operational and sustainable. The above are in accordance with established protocols for fish diseases and with the three key elements of the Invasive Non-Native Species Framework Strategy for Great Britain: Prevention, early detection, surveillance, monitoring and rapid response, mitigation, control and eradication. 40 10.3 Objective III – Electro-fishing Survey A juvenile salmonid survey was completed in 1996 by the Scottish Conservation Projects Trust on behalf of the YDSFB where 59 sites were surveyed, and in the period 20022008, the YDSFB also carried out a number of juvenile salmonid surveys. Future widespread electric fishing is required to establish baseline data as to which species are currently present, their abundance and extent across the YSFD. Due to the importance of the salmonid fisheries, electric fishing will primarily be aimed at these species. Other fish species encountered shall be recorded in full detail in order that future investigations can be targeted, perhaps using additional methods. Targeted data collection on species of conservation importance, such as eels or lampreys may be possible through collaborations with SNH. 10.3.1 Survey Method Electric fishing will be carried out in accordance with the training and methods of the Scottish Fisheries Co-ordination Centre (SFCC). It is recommended that the Time Delineated Method be used in order that. • The greater part of the catchments can be surveyed, including selected areas of wide main stem waters. • Overall trends in relative fish abundance, rather than exact fish numbers, can be determined. This will allow the greatest amount of information to be gathered from across the entire catchment in the limited survey season. The habitat survey will provide more detail on how many minor burns are of a size worth electric fishing, areas of the main stem Ythan and which are unwadeable and should be excluded, and the frequency of sites on the main stem. The findings of the habitat survey will also be employed to ensure that the full range of habitat types found in the catchments are surveyed, including sub-optimal habitat types which may provide an early indication if fish numbers and habitat occupancy falls. To establish robust baseline data selected sites should be revisited in each of the subsequent years of this plan following completion of the habitat surveys. 10.3.2 Electro-fishing Survey – Outcomes Fish species present Numbers and sizes of fish Age class determination DNA samples % habitat utilisation 41 10.3.3 Future Work After a three-year period of gathering baseline data on the fish populations the information can be used to establish an annual monitoring programme using a smaller, but statistically robust, number of quantitative electric fishing sites which will be able to detect any statistically significant changes in the salmonid fish populations. 10.4 Objective IV – Structure of Ythan Fish Stocks The Ythan system and the Water of Cruden have a diverse and complex make up of fish stock components and run-timings e.g. spring, summer and autumn salmon. Throughout the catchment there are separate and distinctive stocks of salmon, sea trout and brown trout which need to be preserved at all cost. It is this diversity of stock which gives the Ythan its 9 month long angling season. Understanding of the structuring of Atlantic salmon, sea trout and brown trout stocks within rivers is essential for focusing local management and stock assessment on breeding populations, the fundamental biological units which underpin recruitment and their character. 10.4.1 Genetics Genetic research shows that in all but the smallest rivers the run of salmon consists of a number of discrete breeding populations which are reproductively and genetically distinct. Understanding the population structure is essential for effective stock management and will allow the conservation of vulnerable components. Samples taken from live fish can be used to identify different breeding populations of salmon living within the Ythan catchment and establish, for instance, whether salmon in the main stem are distinct from those in a particular tributary and should be managed separately. 10.4.2 Genetics Survey Method Fin clips can be removed from live juvenile salmon during the course of routine electrofishing surveys or from adult salmon captured by rod & line, following the guidelines produced co-operatively between RAFTS and Marine Scotland Science (MSS). Data from the habitat survey will help to determine where the spawning grounds are present as discrete stretches on the main stem and therefore likely to be used by distinct populations of salmon. Distinct populations may also occur on tributaries where there is access to more than a few kilometres of available habitat; branching in a river system often leads to distinct salmon populations. Exact locations of genetics sampling of juvenile fish will only be determined after completion of the habitat survey. Currently sample analysis is provided centrally to RAFTS members, and is supported with funding from the Scottish Government. However analysis is costly and it is not known if funding from the Scottish Government is to continue for 2011 and onwards. The earliest sites for analysis should include a broad coverage of the catchments and target areas thought to contribute greatest to the overall stock of salmon, i.e. where salmon are abundant. The sampling programme can be ongoing over a number of years and samples can be stored for analysis when funds allow. 42 10.4.3 Future Genetic Work Planned sampling can be revised in conjunction with the guidance from RAFTS and MSS following completion of the habitat survey. Combining information from the habitat survey and the genetic sampling will help to identify which parts of the river should be considered separately for the management of salmon. Future work may involve identifying separate breeding populations of sea trout for management purposes. 10.4.4 Catch Returns and Scale Analysis 10.4.4.1 Survey Purpose Catch returns for salmon and sea trout submitted annually to the Scottish Government (Marine Scotland) are made publicly available in a summarised form covering the whole of the YSFD and divided into catches January to April and May to December. Since January 2007 the YDSFB have had the statutory authority to request catch information from owners and occupiers of salmon and sea trout fisheries within the YSFD. More information could be gleaned about the adult fish being caught if the individual fisheries in the YSFD were prepared to make their detailed catches available to the River Ythan Trust for examination or if they provided monthly catch figures and fish weights. This would allow changing trends to be assessed such as in the time of year when fish are being caught and in the average weights. There is no legal requirement to submit catches of brown trout and other freshwater fish to the Scottish Government. Establishing a scale sampling programme would allow information to be gathered on growth rates in freshwater, smolt ages and sizes, confirm whether salmon are grilse or multi-sea winter fish, i.e. how long they have spent at sea, the age at maturity for brown and sea trout and the incidence of repeat spawning. 10.4.4.2 Survey Method As a minimum, the YDSFB can ask to receive a monthly breakdown of all the catches which have been submitted to the Scottish Government since 1952, which would provide some indication of how the timing of salmon and sea trout runs for the river as a whole has changed over that period. To allow different parts of the river to be compared permission will need to be sought from proprietors and angling clubs from a number of representative fisheries on the river to access their fishing records. From these sources the numbers of fish of each species caught and their weights can be examined by month for each year and changing trends noted for the whole river and for sub-catchments. It is unlikely that changes in the fishing effort can be fully quantified. If possible the records of the coastal netting stations should be examined for changes in the time of year salmon and sea trout are entering the river. Scale sample packets and training shall be provided for interested anglers and proprietors, in order that salmon, sea trout and brown trout samples can be collected safely and effectively. These scales could then be read by an outside contractor if no in-house personnel were available. 10.4.4.3 Structure Analysis – Outcomes Genetic characteristics of Ythan salmon stocks Species, numbers and weights of fish caught by month Age structure and size of fish at all life stages 43 10.5 Objective V – Evaluate Current Restocking Programme Currently the YDSFB operate a modest restocking programme within the district . Both salmon and trout of known migratory parent origin have been stocked into the Ythan system intermittently and also the Water of Cruden, due to a pollution incident. Stocking of juveniles has been carried out mainly to mitigate against serious pollution incidents which have adversely damaged salmonid stocks and their habitats. The YDSFB do not own their own hatchery facility and subsequently buy in fed fry / parr / smolts from outside commercial units. The most recent year that salmon has been stocked into the Ythan system was 2003. These fry were of Ythan parentage and were reared at a local fish farm. Trout fry and smolts for stocking purposes have been sourced from outside the district. It is the view of Marine Scotland, Scottish Environment Protection Agency, Scottish Natural Heritage and ASFB/RAFTS (Policy Paper 2008) that fish sourced from outside the district for stocking purposes is not recommended, and brood stock should be collected from the immediate area into which the progeny is to be stocked. A formal evaluation of the current stocking programme is urgently required. The evaluation should lay out the objectives of the stocking programme and determine if they are being met. It should take into account the costs incurred and any detrimental impact on the naturally breeding population, and weigh these against any quantifiable benefit arising from the stocking procedure, e.g. increase in juvenile density compared to non-stocked areas. Further considerations are reviewed by Youngson A (2007). 10.5.1 Survey Method The restocking evaluation will involve information gathered from a number of the other surveys on the catchment, in particular the habitat, electric fishing and genetic sampling surveys. Three approaches can be taken: 10.5.2 Habitat Units and Carrying Capacities From the habitat survey the catchment can be divided into units, for instance individual tributaries, and from the areas of fry habitat and juvenile habitat recorded estimates of the salmon carrying capacity can be made. Comparing the estimates with the actual numbers recorded by electric fishing will establish if any tributaries are supporting significantly less than their carrying capacity and these areas can be considered for continued stocking or for other appropriate improvement measures. 10.5.3 Electro-fishing and Juvenile Densities Following on from the first step, the electric fishing data can be examined to determine if there is a particular stage at which fish production is failing. For instance, if adequate fry numbers are being produced for the available habitat but parr numbers are poor, stocking will not increase fish production but other measures such as increasing the number of refuges for parr through boulder addition may be more appropriate. Where fry numbers are poor, for example through poor quality spawning 44 grounds, fully costed comparisons can be made between the restocking operations and instream improvements to determine the most appropriate method. 10.5.4 Genetic Analysis Particular groups of fish are genetically suited to particular locations within catchments and so natural genetic population structuring should therefore be conserved (Youngson, 2007). The juvenile sea trout sourced from outside the district may be more naturally suited to their river of origin and if they are instead stocked somewhere less appropriate or familiar, survival may be greatly reduced. Comparing the genetic make-up of juvenile populations within different tributaries in the upper catchment will help to establish if the populations are distinct and should be conserved as such. 10.5.5 Future Work A revision of the stocking procedure in light of best practice, (FRS, 2003; Youngson, 2007) and the evaluation may be necessary. Any stocking which is carried out should be monitored to ensure it is beneficial, e.g. results in increased numbers of juvenile salmon. 10.5.6 Retocking Evaluation – Outcomes Establish if stocking is beneficial If so, establish where stocking would be most beneficial geographically Determine if stocking is the most cost-effective approach 10.6 Objective VI - Review the survey data gathered to understand the factors affecting the fish populations and prioritise remedies against the detrimental impacts At the end of 2013 a review of the work carried out so far will be necessary. This will review the survey work carried out in the first three-year phase, evaluate the findings and any shortcomings, and prioritise improvement works and research programmes for the next three years. The management targets to achieve in the first three-year period are therefore: • Complete a habitat survey of the entire catchment • Conduct a minimum of two years of initial electric fishing surveys • Relate these surveys to the stocking programme and ongoing genetic results • Establish a robust programme of scale and catch data collation • Identify impacting problems on the catchment and prioritise solutions 45 10.7 Objective VII - Commence restoration of the district and continue to refine knowledge through continued research Small-scale habitat improvements, such as the removal of fallen trees preventing adult fish access to spawning burns which have already been identified during the course of the YDSFB‟s work, can be carried out as and when the current work programme allows. Major habitat restoration works, prioritised at the end of 2013, will be planned in detail and fully costed with a view to beginning improvement works the following year. This will include detailed surveys to calculate the full extent of work required, such as the length and location of fencing, and site specific requirements, for example cattle watering points, in conjunction with the landowner. Funding sources such as the Scotland Rural Development Programme will be approached for financial support. Pre- and post-improvement monitoring of the sites and their surroundings will be builtinto the survey programme. Baseline information on the fish species at the improvement sites before work commences will be compared with data collected from the same sites for the two years following the works. Distinct from the monitoring surveys, the research programme will be refined to include a statistically robust series of electric fishing sites to measure changes in the juvenile salmonid population. 10.8 Objective VIII - Review success of initial restoration schemes and prioritise works for the next five year period By the end of 2015 the data from the monitoring programme will be reviewed to determine the success, or otherwise, of the restoration works carried out to date. Knowledge and experience gathered will be incorporated into future rounds of improvements. At this stage the next Fishery Management Plan, prioritising work in the catchments for the next five years, from 2015 to the end of 2020, will be prepared and consulted upon. 46 Figure 2.0 Proposed Timescale for Projects Operational Objective 2011 Habitat survey of the Ythan Salmon Fishery District May-Sept Biosecurity Plan Production Electro fishing Surveys Jul - Dec Jul-Sep 2012 2013 Lead Partner Partners Possible Funding Sources YDSFB, SEPA SNH , RAFTS (Sco Gov.), SEPA, LEADER RAFTS RAFTS, SEPA, BP RAFTS (Sco Gov.), Atlantic Salmon Trust, Wild Trout Trust YDSFB, RAFTS SEPA River Ythan Trust May-Sept RiverYthan Trust River Ythan Trust YDSFB YDSFB, SEPA Jul - Sep Jul-Sep i) Jul - Sep ii Jan – Feb iii Apr - Oct i) Jul - Sep ii Jan – Feb iii Apr - Oct RiverYthanTrust YDSFB Evaluate current restocking programme Feb-Mar RiverYthan Trust YDSFB Obstruction Removal Programme – Haddo Country Park Lake (Outfall) June - Aug River Ythan Trust SEPA, YDSFB Review and publish data gathered from surveys and plan next two years programme of works. Oct-Dec RiverYthanTrust YDSFB Research structure of Ythan fish stocks i) Genetic Sampling ii) Catch Returns iii) Scale Collection & Analysis i) Jul - Sep iii) Apr - Oct 47 10.9 Continued Management by YDSFB Briefly, the general powers and duties of the YDSFB are to carry out such acts, execute such works and incur such expenses as may appear to them expedient for: The protection or improvement of the fisheries (salmon and sea trout) within their district. The increase of salmon (including sea trout). The stocking of the waters of the district with salmon (including sea trout). 10.9.1 Bailiffing The YDSFB is responsible for carrying out the statutory duties regarding protection of the fishery by policing the river and currently this is undertaken by the superintendent. 10.9.2 Biosecurity The YDSFB will continue its statutory duties regarding protection of the fishery by raising awareness of Gyrodactylus salaris and the potential for it being introduced to Scotland on fishing tackle and equipment that has been used abroad. Also it will be closely involved in the development of the proposed biosecurity plan and its future implementation. 10.9.3 Statutory Consultee The YDSFB is a statutory consultee in connection with developments in the district on or adjacent to rivers and streams that may impact on fish populations, for example, renewable energy generation projects. 11. REVIEW OF THE FISHERY MANAGEMENT PLAN This Fishery Management Plan has a duration of five years covering the initial data gathering phase and the subsequent priority works. 11.1 Annual Review An annual appraisal of the progress made in implementing the plan will be made in December of each year. This will include achievements and the rationale for any deviation from the plan. 48 11.2 Three-Year Review A major review of the plan will be conducted in December 2013 to examine the progress of the plan in relation to the targets laid out in section figure 2.0. This will provide an opportunity to examine the findings to date, to produce the prioritised and budgeted remediation programme, and to lay out research priorities for the next two years. 11.3 Five-Year Review The accomplishments and areas of weakness in implementing the plan will be reviewed in early 2015. This will help to shape future iterations of the plan. 49 12. REFERENCES Alexander, Leaper, Francis and Tulloch (1997) ‘Biodiversity in North-East Scotland: a preliminary audit of habitats and species.’ North-east Scotland Action Plan Steering Group. Bilsby, H. (2008). River Don Fishery Management Plan 2009-2011 Calderwood, W.L. (1909). The salmon rivers and lochs of Scotland. Edward Arnold, London. Carter, T.J., Pierce, G.J., Hislop, J.R.G, Houseman, J.A. and Boyle, P.R. (2001). Predation by seals on salmonids in two Scottish estuaries. Fisheries Management and Ecology; 8; 207-225. Chalmers and Crabtree (October 1999) ‘Modelling Impacts on Nitrate Leaching and Farm Incomes in the Ythan.’ Macauley Land Use Research Institute. Director of Environmental Health, Gordon District Council (1994) ‘Nitrates in Drinking Water – Ellon Area.’ Gordon District Council Donnelly J (February, 1999) Grampian Forest Newsletter E.C. Environment Council (1991) E.C. ‘Nitrates Directive (91/676/EEC)’ Fisheries Research Services. 2001. Scottish Salmon and Sea Trout Catches, 2000: Statistical Bulletin.Fisheries Series, No. FIS/2001/1. Scottish Executive Environment and Rural Affairs Department. Fisheries Research Services, 2002. Scottish Salmon and Sea Trout Catches, 2001: Statistical Bulletin.Fisheries Series, No. FIS/2002/1. Scottish Executive Environment and Rural Affairs Department. Fisheries Research Services, 2003. Scottish Salmon and Sea Trout Catches, 2002: Statistical Bulletin.Fisheries Series, No. FIS/2003/1. Scottish Executive Environment and Rural Affairs Department. Fisheries Research Services, 2004. Scottish Salmon and Sea Trout Catches, 2003: Statistical Bulletin.Fisheries Series, No. FIS/2004/1. Scottish Executive Environment and Rural Affairs Department. Fisheries Research Services, 2005. Scottish Salmon and Sea Trout Catches, 2004: Statistical Bulletin.Fisheries Series, No. FIS/2005/1. Scottish Executive Environment and Rural Affairs Department Fisheries Research Services, 2006. Scottish Salmon and Sea Trout Catches, 2005: Statistical Bulletin.Fisheries Series, No. FIS/2006/1. Scottish Executive Environment and Rural Affairs Department. 50 Fisheries Research Services, 2007. Scottish Salmon and Sea Trout Catches, 2006: Statistical Bulletin.Fisheries Series, No. FIS/2007/1. Scottish Executive Environment and Rural Affairs Department. Fisheries Research Services, 2008. Scottish Salmon and Sea Trout Catches, 2007: Statistical Bulletin.Fisheries Series, No. FIS/2008/1. Scottish Government. Fisheries Research Services, 2009. Scottish Salmon and Sea Trout Catches, 2008: Statistical Bulletin.Fisheries Series, No. FIS/2009/1. Scottish Government. Fisheries Research Services, 2010. Scottish Salmon and Sea Trout Catches, 2009: Statistical Bulletin.Fisheries Series, No. FIS/2009/1. Scottish Government. Fisheries Research Services (2003) To stock or not? Scottish Fisheries Information Pamphlet No 22. 2003. Forestry Commission. 2003. Forests and Water Guidelines (4th Edition). Forestry Commission.Edinburgh, pp. 1-66. Grimble, A. (1899) The Salmon Rivers of Scotland. Hendry, K. & Cragg-Hine, D. (1997). Restoration of Riverine Salmon Habitats: A Guidance Manual.R&D Technical Report W44. Environment Agency, Bristol. Pdf available from publications catalogue http://publications.environment-agency.gov.uk/ Institute of Hydrology (March 1997) ‘River Flow Measuring Station Information Sheet.’ National River Flow Archive Data Retrieval Service. North East River Purification Board (1994); ‘River Ythan; Catchment Review 1994.’ North East River Purification Board. Salmon Assessment in Scotland: Bringing Information Resources into Line with Recent Research on Methods. Scottish Fisheries Research Report, No. 68, 24pp. Scotland and Northern Ireland Forum for Environmental Research. 2006. Handbook of Climate Trends Across Scotland. Scottish Environment Protection Agency (January 2010), Personal Communication, Scottish Executive (November 1999) ‘Designation of Nitrate Vulnerable Zones: The River Ythan Catchment and Estuary.’ Scottish Executive Rural Affairs Department. Scottish Fisheries Co-ordination Centre (2007). Habitat Surveys. Training Course Manual. SFCC, Pitlochry, Perthshire. 64pp. Scottish Natural Heritage (1995) ‘Forvie National Nature Reserve Management Plan.’ Scottish Natural Heritage. Youngson A (2007) hatchery work in support of salmon fisheries, Scottish fisheries Research Report No 65 Ythan District Salmon Fishery Board (2010), Personal Communication 51 Ythan District Salmon Fishery Board Survey of Atlantic Salmon and Trout Populations of Selected Tributaries within the River Ythan Catchment by Isla Martin and the Scottish Conservation Projects Trust (1996). Ythan Project (2000) Bringing Communities Together. Ythan Project Final Report (2005) LIFE00 ENV/UK/000894 (Project beneficiaryAC, project partners - FP, FE, {now FC} MLURI, RRC, SNH, SEPA and YDSFB) AC Aberdeenshire Council FP Formartine Partnership FE Forest Enterprise – now known as Forestry Commission Scotland MLURI Macaulay Land Use Research Institute RRC River Restoration Centre SNH Scottish Natural Heritage SEPA Scottish Environment Protection Agency YDSFB Ythan District Salmon Fishery Board 13. ACKNOWLEDGEMENTS The preparation of this fishery management plan has been supported by grant funding from the Scottish Government as part of a national programme of fishery management planning. The programme coordination and management is by the Rivers and Fisheries Trusts of Scotland. (RAFTS) The Ythan District Salmon Fishery Board and their River Superintendent, Mr Sandy Milne, have provided a large amount of information which is much appreciated. We would finally like to thank Aberdeenshire Council kindly whom gave access to, and permission to use information contained within the reports and archives of the Ythan Project. (LIFE00 ENV/UK/000894) The River Ythan Trust also acknowledges the useful comments given during the consultation process by Aberdeenshire Council, Marine Scotland, Scottish Environment Protection Agency, Scottish Natural Heritage and others. 52 14. GLOSSARY AC - Aberdeenshire Council ASFB – Association of Salmon Fishery Boards AST- Atlantic Salmon Trust BP – British Petroleum DBIT – Deveron, Bogie and Isla Rivers Charitable Trust FC – Forestry Commission Scotland FMP – Fishery Management Plan FP – Formartine Partnership FRS – Fisheries Research Services (now part of Marine Scotland) GBR – General Binding Rule GIS – Geographic Information Systems INNS – Invasive Non- Native Species LEADER – Liaisons Entre Actions de Developement de L'Economie Rurale (Links between actions for the development of the rural community) MLURI- Macaulay Land use Research Institute MS – Marine Scotland (part of Scottish Government) MSS – Marine Scotland Science NERPB – North East River Purification Board NNR – National Nature Reserve NVZ – Nitrate Vulnerable Zone RAFTS – Rivers & Fisheries Trusts of Scotland Ramsar – Ramsar Convention (The Convention on Wetlands of International Importance, especially as Wildfowl Habitat) RBMP – River Basin Management Plan RSNC – Royal Society for Nature Conservation RRC – River Restoration Centre RSPB – Royal Society of Protection of Birds RVS – Red Vent Syndrome RYT – River Ythan Trust SEPA – Scottish Environment Protection Agency SFCC – Scottish Fisheries Coordination Centre SNIFFER – Scotland and Northern Ireland Forum for Environmental Research SNH – Scottish Natural Heritage SRDP – Scottish Rural Development Programme SSSI – Site of Special Scientific Interest YDSFB – Ythan District Salmon Fishery Board YFMP – Ythan Fishery Management Plan YSFD – Ythan Salmon Fishery District YPV – Ythan Project Volunteers 53 15. APPENDICES Appendix 1- YTHAN VOLUNTARY CODE 2011 SEASON General Rules. All kelts, coloured fish, salmon and sea trout parr, smolts, and brown trout under 10 ins. to be returned carefully to the water. All salmon caught before the 31st May to be returned carefully to the water. All sea trout caught after 30th September to be returned carefully to the water. All finnock (immature sea trout) to be returned carefully to the water. All foul hooked fish (hooked behind the head) to be returned carefully to the water. No rod caught fish to be sold. (It is illegal in Scotland to sell rod caught salmon or sea trout.) Bag Limits (Fish killed) Over the Entire River by Any One Angler. Bag limits are not targets; anglers should only retain fish they will use. Anglers are encouraged to return fish. (Especially hen fish.) Annual bag limit for salmon and grilse (combined total) shall be 4 fish. Daily bag limit for salmon and grilse (combined total) shall be 1 fish. Annual bag limit for sea trout shall be 6 fish. Daily bag limit for sea trout shall be 2 fish. Baits and Lures. No live or deadbait (other than worms) to be used. Barbless or de-barbed hooks are recommended. Only one treble hook per lure is recommended. Fish Landing Equipment. The use of gaffs and tailors are not permitted. Only knotless landing nets are permitted. Handling and Returning Fish Treat fish with care and respect. Fish should not be lifted, otherwise unsupported, by the wrist of the tail, or damage to the spine may result. Similarly holding up fish by the gill covers may well inflict mortal injury. If fish are to be kept, dispatch them quickly with a forceful blow from a suitably hefty instrument. Fish to be returned should be held firmly and unhooked quickly, using forceps. Fish to be returned to the water should be carefully supported, head to the current, and held until recovered sufficiently to swim free. (This may take several minutes.) 54 Appendix 2 - DATA EXTRACTED FROM THE YTHAN PROJECT Site Ref River / burn Mid site grid ref Location Description YP0 Bronie NJ924301 Due north of Littlemill of Esslemont YP1 YP2 Ythan Youlie NJ822392 NJ875314 U/s of Gight Castle D/s of Sonach Croft YP3 Ythan NJ947304 Meiklemill, Ellon YP4 YP5 YP6 YP7 Ythan Ythan Ythan Ythan NJ964304 NJ927307 NJ863367 NJ922319 The Meadows, Ellon Esslemont, Ellon Gurge Pot, Methlick Ardlethen Quarry, Ellon YP8 YP9 YP10 YP11 YP12 YP13 YP14 YP15 Ythan Ythan Ythan Ythan Ythan Ythan Ythan Ythan NJ906333 NJ899349 NJ885361 NJ848384 NJ834394 NJ806385 NJ793376 NJ787366 YP16 YP17 YP18 YP19 YP20 YP21 YP22 YP23 YP24 YP25 YP26 YP031 YP032 YP033 Ythan Ythan Ythan Ythan Ythan Ythan Ythan Ythan Ythan Ythan Ythan Foveran Foveran Foveran NJ771374 NJ761385 NJ762403 NJ753418 NJ746346 NJ734431 NJ719420 NJ706405 NJ697389 NJ687379 NJ668384 NJ985243 NJ970239 NJ953243 Quarrybrae, Auchedly, Ythanbank Schivas, Ythanbank Tangland, Methlick Methlick Woods, Methlick Crook a Peel, Gight, Methlick Fetterletter, Woodhead, Fyvie Minnonie, Woodhead, Fyvie Brewers Pot, d/s of Newbigging. Fyvie Mill of Crichie, d/s of Fyvie Maitland’s Bridge, u/s of Fyvie Home Farm u/s of Fyvie Reimshill, Inverythan Towie Barclay Wester Milltown Kirkton of Auchterless Mains of Templand Badenscoth Haughs Logie Aulton Downstream of Foveran Church Upstream of Foveran School Due south of Mill of Fiddes YP034 Foveran NJ933236 Due south of Hill of Fiddes YP035 Foveran NJ919224 North of Auchloon Farm YP036 Foveran NJ904220 North east of Hillbrae Farm YP037 Lt Water NJ841395 Upstream of Chapelhaugh YP038 Lt Water NJ842410 Burnend Invasive plants Other Comments Water depth Weir (1) Maj Sluice (1) Maj Br (1) Min Br (2) Maj Outfall (1) Maj Br (1) Maj Outfall (1) Maj 150mm Weir (1) Maj Himalayan Kw Weirs (2) Maj Weirs (3) Int Br (1) Min Br (1) Maj Giant Hw Jap Kw Br (1) Int Br (1) Int Cul (1) Maj Br (1) Min Br (1) Min Weir (!) Maj Weir (!) Maj Br (2) Weirs (2) Min C W (2) Cul (1) Maj Weir (1) Min Br (2) Min Cul (2) Maj Br (1) Min BR (1) Int Br (2) Min Br (1) IntWeirs (2) Min 55 250mm 100mm 450mm 750mm 500mm 600mm 750mm 1000mm 1000mm 750mm 550mm 1300mm 400mm 500mm 750mm 700mm 200mm 150mm 500mm 400mm 300mm 150mm 150mm 200mm 600mm 200mm 350mm 300mm 100mm 250mm 250mm 100mm 250mm 220mm Site Ref River / burn Mid site grid ref Location Description YP039 Lt Water NJ849431 Downstream of Newmill YP0310 Lt Water NJ843442 Cairnbanno House YP0311 Lt Water NJ838463 Upperton of Cairbanno YP0312 YP0313 Lt Water Lt Water NJ836483 NJ831500 Upstream of Allathan House Greens of Middlehill YP0314 Keithfield (Kelly) NJ881350 Downstream of Haddo Lake YP0315 Modley NJ950304 In Ellon YP0316 Ythan NJ763394 Fyvie Castle YP0317 Youlie NJ873309 Upstream of Sonach Croft YP0318 YP041 YP041A YP042 YP042A Youlie Wedder Youlie Wedder Keithfield (Kelly) NJ875314 NJ898338 NJ875314 NJ894335 NJ880347 Downstream of Sonach Croft Mill of Auchedly, Ythanbank Downstream of Sonach Croft South of Northseat Haddo Lake YP043 YP045 Wedder Youlie NJ887336 NJ854291 South of Little Meldrum Upstream of Braeside / Craigies YP046 Youlie NJ849289 Downstream of East Cattie YP047 Youlie NJ846288 East Cattie YP048 YP049 Youlie Youlie NJ842285 NJ837281 Downstream of Kilblean Upstream of Kilbean Invasive plants Other Comments Water depth Weirs (2) Min 150mm Br (1) Int Br (1) 200mm Min C W (2) Pond Ford Maj 100mm C W (1) 150mm Cul (1) Maj 50mm CW (2) Weir (1) Min 100mm WF (2) Br (1) Min Cul (2) Maj 200mm Weirs (2) Min Br (3) Min Jap Kw Rhod Br (1) Int 300mm (Weir does not exist) Br (2) Int Weir 200mm (1) Min Weirs (2) Min 70mm Ford (1) Min 150mm Br (1) Min 50mm Cul (1) Maj 100mm Br (1) Min 100mm Giant Hw Cul (3) Maj 50mm Br (1) Min Weir 200mm (1) Min CW (2) Cul (2) Maj 100mm Br (1) Min “In Burn” dam 200 -300m long Cul (1) Maj 100mm 300m long Weir metal+rubble no buffer zone 50mm Br (2) Min CW 50mm (1) Poaching Ochreous water 56 Site Ref River / burn Mid site grid Location Description ref Invasive Plants Other Comments Water Depth YP0411 Sauchentree NJ855372 Methlick YP0412 Keithfield NJ832342 Hillbrae YP0412 Bronie A NJ857262 Upstream of Cairnfechel YP0413 Keithfield NJ829347 Upstream of Hillbrae Mimulus CUL (2) Maj sp. Br (1) Min Weir (1) Int Weirs (2) min Weir (1) Maj CW (3) Cul (1) Maj Weirs (2) Min Br (1) Min Cul (1) Maj CW (2) YP0414 Keithfield NJ828352 Upstream of Hillbrae Croft YP0417 Keithfield NJ826347 Downstream of Bankhead YP0418 Keithfield YP0419 Keithfield NJ822347 NJ816353 Bankhead Bogside YP0420 Keithfield NJ811355 Den of Kirkton 150mm 200mm 140mm 500mm Septic tank outflow 80mm Cattle access to burn 4 points Cul (3) Maj 300mm CW (1) Poaching 350mm Cul (1) Maj 400m 450mm long Cul (2) Maj old duck 800mm shoot pond Ochreous water 57