Concurrent Collapses of Demersal Fish and Sea Trout (Salmo trutta) on Scotland’s West Coast Following the Removal of the “Three-Mile Fishing Limit”

Abstract

Salmon farming has been blamed for the collapse of the sea trout (Salmo trutta) fishery in Loch Maree on Scotland’s west coast despite the absence of any direct evidence. Stocks of west coast demersal marine fish, especially around the Clyde Estuary have also declined over a similar time span. The decline of these marine fish stocks can be attributed to the removal of the “three-mile fishing limit” in 1984 by UK Government legislation. Sea trout inhabit the same inshore waters as targeted demersal fish and can be caught as by-catch. Comparisons of the decline of demersal species and the sea trout from Loch Maree and the west coast show a high degree of correlation. Stocks of whiting (Merlangius merlangus) from inshore waters have found to consist of small fish which mirrors the stock makeup of the Loch Maree sea trout stock.