Towards a strategy for the conservation of marine fish in Scotland

Abstract

SynopsisThis paper reviews the status of marine fish populations in Scottish waters and considers current and potential threats. The inshore environments considered (shallow sandy bays, deeper and muddier areas, sea lochs, estuaries and firths) can be characterised by fish communities of 20-50 species, with some 20 species being present at any one locality. All of them functioned as nursery areas for commercial species and as habitats for smaller non-commercial residents. As few as 3-5 species were dominant, in terms of both numbers and biomass, in each habitat. More species occurred on the open shelf (over 200 ?) with up to 90 being taken regularly, but only 10 species accounted for 90% of both total biomass (in each of three North Sea areas) and commercial landings in Scotland by U.K. vessels. Mackerel (32.3%), herring (20.4%) and haddock (14.7%) dominated the landings. Both coastal fish communities and shelf stocks of commercial species have historically suffered from over-exploitation, a situation that has continued to date despite changes in management leading to their supposed protection. Other threats are identified, as is the need for conservation, while some legislative and research recommendations are made.