D. Mills – författare

Reviews advances in the understanding of the biology, ecology and management of the Atlantic salmon throughout its geographical range, and examines the effects on salmon of afforestation, pollution, acid rain, water abstraction and changing agricultural methods. The rapid escalation of salmon farming with its impact on wild stocks is analyzed as is the increasing threat of over-exploitation on both the open seas and in home waters.

The Alantic salmon (Salmo salar) is a fish of major biological interest and economic importance. Recent years have witnessed major advances in the understanding of the many facets of the biology, ecology and management of this fish. The author, Dr Derek Mills, covers all major aspects of the atlantic salmon throughout its geographical range in the northern hemisphere. There is a great awareness today of the effects on the salmon of afforestation, pollution, acid rain, water abstraction and changing agricultural methods. There has also been a rapid escalation of salmon farming which is beginning to have an impact on wild stocks. The author discusses these issues, also considering the increasing threat of over exploitation of the atlantic salmon.

At present fishing for salmon in Norwegian home water is carried out with drift nets, bag nets, bend nets, lift nets and stake nets in the sea, and mainly by rods in the rivers. Catch statistics have been collected since 1876, but reliability of the statistics is questionable. The rates of exploitation on many Norwegian salmon stocks are very high, and data are presented and discussed for River Laerdal, River Eira and River Imsa stocks. As a result of this heavy exploitation with nets, the frequency of net-marked salmon entering rivers is high especially for griIse, although most net-marked salmon are only slightly damaged. It is suggested that mortality of salmon that are net-damaged hear or in brackish water is relatively small compared with salmon that escape from nets on the high seas. Some possible effects of selective fishing are also discussed. 159 Status of Exploitation of Atlantic Salmon in Norway REFERENCES Anon. (l985a) Salmon and sea trout fisheries 1984. Central Bureau of Statistics of Norway, Oslo - Kongsvinger, 96 pp. (in Norwegian with English summary) Anon. (I985b) Report of meeting of working group on North Atlantic salmon. ICES C. M. 1985/ Assess, 11, 67 pp. Angelsen, K. K. and Holm, M. (I978) Rapport om garnforslllk med laks, Fisk og Fiskestell, . ; 15-17. (in Norwegian) Berg, M. , Abrahamsen, B. and Berg, O. K. (I986) Spawning of injured compared to uninjured female Atlantic salmon, Salmo salar L. Aquaculture and Fisheries Management, l.