Salmon ranching experiments in the River Imsa: returns of different stocks to the fishery and to River Imsa
Hansen, L.P.; Jonsson, B. (1989). Salmon ranching experiments in the River Imsa: returns of different stocks to the fishery and to River Imsa, in: De Pauw, N. et al. (Ed.) Aquaculture: a biotechnology in progress: volume 1. pp. 445-452 In: De Pauw, N. et al. (1989). Aquaculture: a biotechnology in progress: volume 1. European Aquaculture Society: Bredene. ISBN 90-71625-03-6. 1-592 pp., more |
| Available in | Authors | | Document type: Conference paper
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| Abstract | During the springs 1981-1984, 154311+ and 420812+ smolts of Atlantic salmon (Salmo salar L.) from 12 different stocks were released at the mouth of the River Imsa, southwestern Norway. Two-year-old smolts gave higher total yields of adult salmon than one-year-olds. Smolts released in 1981 and 1982 gave higher yields than smalts released in 1983 and 1984. The proportion of salmon caught in the long-line fishery at the Faroes and in the northern Norwegian Sea was highest for the multi-sea-winter stocks and negligible for the grilse stocks. Due to high fishing pressure in the sea, the return-rate to the River Imsa was low. When correcting for tagging mortality and non-reported tags, the salmon ranching at Ims was on the average profitable for Norway , but not as a private enterprise. |
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