YOU suggest that the fish farming and wild fish community should get together to discuss issues and tackle the problems (Leader, 7 November).
Fish farms were introduced in the 1970s to the migrating waters of salmon and the feeding grounds of sea trout. The fish farms – because of their intensive farming – soon became a breeding ground for sea lice, which threatened the young wild salmon and sea trout. Young fish netted for science are regularly found with between 40 and 100 sea lice eating their flesh (11 sea lice are said to kill a young fish).
Consequently, sea trout fishing soon collapsed and with it many jobs lost for ghillies and in the tourist industry. The salmon are also at risk from this increased lice burden and a recent survey by the Royal Society B: Biological Sciences states that 48 per cent die from lice emanating from the fish farms.
The salmon farmers cannot control their sea lice for the wellbeing of the wild fish and the lice are now becoming increasingly resistant to the cocktail of chemicals used. The Scottish Environmental Protection Agency is monitoring chemical residues along the scenic west coast – and the faeces and rotting food lying on the sea bed from the caged fish – with alarming results. The clean, unpolluted waters that belonged to the wild salmon and sea trout have been changed beyond all recognition – and now the politically influential farmers are looking to increase production through a new Chinese market. It is unlikely west coast salmonoids will survive this final onslaught.
Rhidorroch Estate Argyle Street, Ullapool
For many years – even before salmon farming – approximately only 6 per cent of the juvenile salmon on their sea migration survived to return to their native river as mature salmon.
The problem is even worse for salmon survival from egg to smolt, the juvenile salmon exiting the rivers for the sea after three or four years’ growth in the rivers. Climate change – bringing frequent heavy storms which wash out the breeding gravel – and protected predators take their toll, resulting in less than 0.6 per cent survival from egg to smolt.
Anglers commission reports to allege that sea lice from salmon farms are the culprits for the growing numbers of Scottish anglers’ failure to catch salmon.
Your Comment states that “both sides [anglers and salmon farmers] should get together, discuss issues and agree on joint action to tackle the problems”.
This action has already taken place with the west coast salmon river, Carron. Restocking with native juvenile salmon, grown under hatchery conditions, along with investment by the river owners and substantial financial support from local salmon farmers has resulted in the annual catch increasing from four to 400 salmon.
If other river owners followed this example, salmon angling would match the substantial salmon farmers’ contribution to the Scottish economy.