Atlantic Salmon (Salmo salar) On and East of the Grand Bank

Abstract

Exploratory fishing with surface gillnets on the Grand Bank and eastward of the Bank over oceanic depths in May of 1979and 1980 revealed the presence of Atlantic salmon (Sa/rna safar L.) at most stations where surface temperatures ranged from 3.8° to 7.5° C. These temperatures were more prevalent in the oceanic area and salmon were found in greater abundance there than on the Grand Bank. Of 341 salmon which were caught, 169 were tagged and released after scales were taken for ageing. Information on tagging locations of three salmon which were caught with tags attached and the distribution of recaptures of 12 salmon from the offshore tagging indicated that the offshore population consisted of migrants from Newfoundland, Nova Scotia, New Brunswick and Maine rivers. The sea-age composition of the catch and the gonad condition of the sampled catch indicated that some of the salmon were maturing to spawn as grilse which had spent only one winter at sea. Apart from their capture in coastal fisheries, this is the first record of grilse being caught in offshore areas of the Northwest Atlantic. Analysis of sea-surface temperature charts for 1978-83 indicated that favorable conditions (4° to 8° C water) persist for salmon in January and April, implying that the eastern and southern Grand Bank region may represent not only the route by which maturing salmon migrate from the Labrador Sea to their home rivers in eastern Canada and northeastern United States but also a major feeding and overwintering area. Comparison of catch rates of salmon from commercial and research fishing off West Greenland and in the Irminger Sea with those of the Grand Bank region implies that the feeding population east of the Grand Bank was quite large in 1980.