Adventure activity on rivers and streams during the spawning season It was suggested at recent meeting which was attended by a representative of

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1 Adventure activity on rivers and streams during the spawning season It was suggested at recent meeting which was attended by a representative of Canoe Wales that it may be useful for Conwy Valley Fisheries and Conservation Association (CVF&CA) to explain our concerns about adventure activity during the spawning season (Nov to end January) and provide information on what our association does together with some information on the life cycle of salmon (in layman s terms) and why we are requesting paddlers to keep out of our spawning areas.. Our association exists to conserve and improve the salmon stocks within the Conwy catchment to the levels that previously existed. At this point may I also dispel the myth that EA(W) stock the rivers for anglers, they do not. The environment agency has a statutory duty to maintain fish stocks and only stock rivers in order to mitigate where the spawning population has reached dangerously low levels or where rivers have suffered a major fish kill due to pollution. The work undertaken by CVF&CA is funded through our member contributions, we get no funding from EA(W) but we are assisted by EA(W) fisheries staff who provide technical advice and training as and when needed. We pay EA(W) to produce salmon parr from broodstock which we collect and take to the EA(W) Mawddach hatchery we aim to stock approx 8000 salmon parr each year. The parr are kept at the hatchery until they are large enough to transport at which point our volunteers collect them usually in July/August and take them to our semi-natural smolt ponds at Roman Bridge (Afon Lledr), Capel Curig (Afon Llugwy) and Hafod Dinbych (Afon Nug) where they are fed and looked after by volunteers until they are released into the rivers in spring the following year. It will be up to three years before these parr return to the Conwy as adult fish to spawn. Our stocking program has been running for over 10 years and we are finally seeing the results of our work with increasing numbers of salmon returning to the Conwy river system. The long term plan is to re-establish a natural spawning population to the level which existed pre1950. From 1950 onwards forestry plantations which drain the hillsides causing acid flushes and use of powerful insecticides in agriculture resulted in the depletion of the salmon stocks to a dangerously low level. The banning of certain insecticides has improved the numbers of invertebrates in our rivers and streams and fish survival is now greater but population densities are still low. Association volunteers in conjunction with the Clwyd & Conwy Rivers Trust ( ) carryout regular invertebrate studies in order to provide an early warning of any potential pollution incidents and generally monitor the health of the rivers and streams within the catchment. We also assist in carrying out enhancement improvements as and when necessary. Increased adventure activity over the known spawning areas is now putting all of this hard work at jeopardy. The life cycle of salmon has been well documented and there are many technical papers on their reproductive cycle the following is a layman s guide to what these papers say: Salmon return from their sea feeding grounds and enter rivers as early as January in some river systems. For the Conwy salmon do not enter in any great numbers until early May. Cock and hen fish turn red during the spawning season which is why nests built by salmon are known as redds. The closer to spawning a fish enters a river system the faster it changes colour. In the sea fish are silver as protection against predation as most predators attack from below and being silver reflects surface light which provides a degree of camouflage for the fish. On entering a river salmon start to loose their silver colour, the change in colour from bright silver to reddish brown can take several months and depends on the time of year the fish enters fresh water.

2 Salmon start to move onto the spawning beds usually after a spate followed a drop in water temperature in the late autumn, this can be as early as October but it is more usual to be from mid November to the end of December. Spawning can take place throughout this period as fresh fish arrive during December. Hen fish, as with all egg laying creatures, select a nesting site (redd) and will defend this site against other fish until ready to spawn. It takes a salmon typically between 3 and 5 days to build a redd. During this building period salmon as with nesting birds are susceptible to disturbance it is a criminal offence to disturb both nesting birds and fish. Salmon redds are shallow depressions in the gravel (but can be up to a meter deep!) excavated by the salmon lying on its side and flapping its body, this results in gravel being displaced due to the pressure difference between the salmon and the river bed, creating a shallow hole (nest) in which the salmon will lay her eggs. Salmon gauge the depth and water flow in their redd by using the anal fin to determine both depth and water flow. Well oxygenated water flow is critical for the development of the eggs. Once the redd is constructed the hen fish will rest until conditions are right for spawning during this period cock fish shadow the hen fish and will fight other cock fish making good use of the kype (hook) which develops in the lower jaw of mature cock fish. Disturbance during this resting period may cause the salmon to abandon its redd and as salmon stop eating when they leave their sea feeding grounds they have to rely on stored fat for nest building and spawning. A fish disturbed from a redd may not have sufficient energy to build another nest This photograph shows a typical cock fish with a pronounced kype but not yet in full spawning colourers. The photograph below shows a cock fish in full spawning colour being used to fertilise eggs at the hatchery. When the hen fish is ready to spawn she positions herself in the redd and gapes i.e. opens her mouth wide, this is the signal for a cock fish to come along side and shed his milt. In addition to large cock fish sexually mature salmon parr can, and do, fertilise some of the eggs. Once the hen fish has shed all her eggs (approx 4000 from a 5lb fish more from larger fish) she moves slightly upstream from her redd and flaps her body in order to cover her eggs with gravel, some eggs are lost in this process hence the large number of eggs laid. This photograph shows eyed ova i.e. you can se the fish within the egg. A hen fish will stay close to her redd to defend it from other hen fish who may start to over cut her redd i.e. build a second redd on top of an existing redd. Cock fish will hang around

3 the spawning area and will fertilise as many hens as they can this tends to result in a high mortality rate of cock fish. You may see dead or dying cocks lying on their sides in the shallows adjacent to spawning areas. Fish that survive the rigors of spawning are known as kelts these fish can hang around in the river until May and are often confused for fresh fish as they once again turn silver in readiness for their return to the sea. Those that survive and make it back to sea will not normally return for at least two years. It is unusual for Atlantic salmon to spawn more than twice in their life time. The eggs remain in the gravel for around 90 days but water temperature has an effect on the eggs hatching, it takes longer if water is cold and is quicker if the water is warm. For the first few days after the eggs are laid they are susceptible to impact damage and will die if shocked, after about a week the eggs harden and are more robust but even so they can be easily damaged. On hatching the small fish are known as alevin they survive on the remnants of their egg sack staying in the interspatial gaps between the gravel until they finally emerge from the gravel when their eggs sacks have been used up. The gills of alevin are very small which makes them extremely susceptible to water quality i.e. pollution and acidic run-off. Once fry emerge from the gravel they start to feed. A cold period at this time can limit the available food source and in these conditions many perish due to lack of food. Once out of the gravel fry and parr are predated on by other fish and fish eating birds i.e. heron/goosander/merganser and king fishers, larger fish will be taken by cormorants. Those that survive will set up territories in riffles and glides between pools until they are ready to smolt (return to the sea). For protection fry and parr are camouflaged and are dark in colour. When salmon parr are getting ready to return to the sea they gradually become silver it is at this point that they become known as smolts. As the smolts migrate they form into shoals as protection against predators and can be seen above natural and manmade structures during low flows unfortunately these large shoals attract a range of predators that do considerable damage to the numbers which finally reach the sea. When they reach the sea smolts feed initially on plankton and larvae of sea fish following the drift of plankton to their main feeding grounds in the arctic. Some smolts who have missed the main plankton blooms stay around the coast and may return to spawn the same year that they left the river, these salmon are known as grilse and tend to be much smaller than the fish that spend two or three years at sea. Mortality rates both in river and at sea is high with only about 10% of smolts which leave a river returning to spawn which is why anything that endangers spawning activity is unacceptable. Without successful spawning fish stocks will rapidly decline. It is the role of EA(W) to monitor fish stocks and when it becomes apparent that the density of parr is low they will introduce controls in order to mitigate losses and prevent further decline. CVF&CA exists to look after the salmon stocks in the Conwy river system. The Association is determined to protect the spawning areas and have worked with EA(W) who have placed information boards at known entry points used primarily by paddlers. Unfortunately this has been construed as an attempt to prevent access to rivers but nothing is further from the truth. The guidance provided to paddlers on the EA/EA(W) web site expresses an opinion that

4 under certain conditions paddling is environmentally benign, sadly this is not always the case. The impression given on the EA web site is that providing paddlers do not trample redds they do no harm. Unfortunately this warning is part of the code of conduct applicable to the Wye & Usk Foundation (WUF) where there are access agreements and a legal right to paddle. The Wye is a much larger river but even so it is failing to meet its salmon spawning targets it is unclear why this is as a considerable amount has been invested in enhancement programmes unlike the WUF who choose not to stock the Wye CVF&A choose to restock the Conwy river to kick start the revival of a once famous salmon river. In North Wales our rivers generally rise over rock and with the exception of a major flood they run clear. This coupled with the size of our rivers (typically 3 to 5m in width) over spawning areas means that even in good flows the possibility of disturbing fish who are preparing redds is high. The EA report W266 - the effects of canoeing on fish stocks and angling expresses an opinion that paddlers do no harm to overall fish stocks. In fact it does not say no harm will be done to fish stocks with respect to migratory fish where spawning grounds are over shallow rocky rivers. The expert witnesses in part two of this report express concern about continuous activity over spawning areas for migratory fish. It must also be borne in mind that the report is talking about overall fish stocks and not individual river stocks of fish. In order to determine if fish are disturbed by paddlers a trial was carried out by EA(W) fisheries staff on Afon Lledr using a single kayak over a known spawning pool. A video record was made of this trial. A cock fish was observed in the tail of the pool and the paddler was asked to proceed down the pool keeping away as much as possible from the salmon under observation. As the kayak moved down the pool it disturbed a pair of fish which had not been seen. As these fish panicked in the pool the cock fish also panicked and shot off upstream. This clearly demonstrates that a single kayak under controlled conditions disturbs fish which may have been spawning. It has been argued that as the cock fish returned to its lye after 20 minutes no harm was done. However it was clear that fish had been disturbed and under SAFFA it is a criminal offence for anyone who wilfully disturbs spawn or spawning fish on any bed bank or shallow where spawning fish maybe. As the EA spawning maps are located at key access points used by paddlers it has to be assumed that their actions are indeed wilful i.e. they are aware that their actions may disturb fish which maybe in the act of spawning and they have chosen to ignore the fact that fish maybe spawning in this area of river. It has been clearly demonstrated that a single kayak disturbs fish which may have been in the act of spawning. If for example a group of four kayaks taking up most of the river width drop into a pool any salmon can only escape what they perceive as predators by running downstream and in so doing abandoning their redds. It has been said that kayaks and open canoes are no worst than a log coming down river. The difference between a log and a paddler is acoustic noise caused by the paddles; the seal like shape of a kayak does not help. In addition logs and trees tend to come downstream in major spates and under such conditions fish move out of the main current and therefore avoid such detritus. This is why minimum height restrictions are imposed on rivers which have access agreements. However even where there are agreements there is no environmentally safe height which can be applied along the full length of a river: what is deemed environmentally safe at one point on the river may not be environmentally safe at another point. The redds must be protected and left undisturbed during the spawning season this applies to all river users including anglers who are guilty of disturbing spawning fish/spawn when wading whilst grayling fishing on some Welsh river (there are no grayling in the Conwy). We are not for one moment suggesting that anglers and adventure activity groups who enjoy the pleasures of our beautiful waterways are wilfully causing serious environmental damage, they do so because they are totally unaware of the environmental sensitivity of areas were they go to enjoy themselves. We would ask all who enjoy our rivers to apply the

5 precautionary principle and where there are no safe water height markers avoid paddling or seek appropriate advice. You can find out if you are on a river where spawning takes place and if your activities may cause disturbance by referring to the Conwy salmon and trout spawning map. For more detail on specific spawning areas talk to the local Environment Agency fisheries officer for the Conwy by phoning We really do not want to see paddlers (or anglers for that matter) in court for SAFFA offences and would request that you co-operate in keeping away from our spawning areas between November and the end of January. There are areas on the river where paddling can be carried out without any major environmental impact but making access arrangements to these areas is proving problematic at the moment.