Changes on horse mackerel (Trachurus trachurus) catch distribution in the Northeast Atlantic

Abstract

The distributions of international commercial catch data were mapped by ICES rectangle and quarter from 1983-1994. These indicate a northward expansion of horse mackerel distribution in the Northeast Atlantic since 1987. The spatial variability of the yearclass abundance of horse mackerel over the European shelf and shelf edge is investigated using international bottom trawl survey data. The aim is to determine if the northward expansion of horse mackerel distribution is due to the extremely strong 1982 yearclass. How the changes in oceonographic conditions since 1989 may relate to the fish northward expansion is also discussed.