ON THE NORTH ATLANTIC ALBACORE STOCK AND ON ITS POTENTIAL SUB POPULATIONS

SUMMARY This paper discusses the potential biological heterogeneity of the North Atlantic albacore stock. Based on the historical work by Aloncle and Delaporte in 1974, the paper keeps the hypothesis that at least 3 sub populations, well stratified & following an east west gradient of longitude, could have been exploited by the albacore surface fisheries. This heterogeneity of the stock has not been taken into account in the present stock assessment by SCRS, but it could play a major role in the fishery trend, as the present shrinking of the historical fishing zones could have produced a decline of the present stock MSY. Scientific investigations are actively recommended to solve this major uncertainty in the stock structure of the Northern Atlantic albacore stock and to better evaluate its potential impact on the stock assessment results. RESUME