Size and MEP-2* variation in juvenile Atlantic salmon (Salmo salar) in theRiver North Esk, Scotland

The relationship of size to MEP-2* genotype was investigated in 0+ juvenile Atlantic salmon (Salmo salar) in the River North Esk, Scotland. Significan t temperature-associated MEP-2*: heterogeneity was observed among tributari es and, in the two tributaries studied, size and MEP-2* genotype were signi ficantly associated. No size association, or heterogeneity among tributarie s, was found for the other allozyme polymorphisms screened. The results sug gest that the association between size and MEP-2* variation, noted by other s, is likely to be widespread in wild populations, and potentially linked t o habitat temperature. Crown (C) 1999 Published by Editions scientifiques e t medicales Elsevier SAS.