Ekman transport and sardine yields in Western Iberia

Abstract

Sardine catches in the coastal waters of Portugal and western Galicia (ICES area IXa) are examined on a regional basis. Catch trends in the northern and southern parts of this area tend to be of opposite sign. Since Bakun indices calculated for the northern and southern limits of the region, and for a station in the centre, are all positively correlated, the links between upwelling and catch must be more entangled than previously surmised. Evidence is summerized which indicates that several distinct atocks may exist in this area. It is suggested that if Ekman drift plays a role in larval recruitment, then the northerly as well as the easterly component must be taken into account.