SEASONAL DIET OF PORTUMNUS LATIPES (PENNANT, 1777) (DECAPODA, PORTUNIDAE)

The seasonal composition of the diet of the infralittoral portunid crab, Portumnus latipes was determined, based or, an analysis of 92 individuals collected from Imeros beach (northern Aegean Sea) during the four consecutive seasons of 2004. P. latipes seems to be an omnivorous species, mainly feeding on macroinvertebrates while macroalgae also participated in its diet. In winter, spring, and autumn, the dominant prey categories were Crustacea followed by Polychaeta and macroalgae, while in summer the order was Polychaeta followed by Crustacea and macroalgae. The observed seasonal differences in the composition of the diet of this species seem to reflect corresponding seasonal population changes of its preys. P. latipes seems to have a diet similar to its midlittoral congeneric, Portumnus lysianassa, since when wave action is reduced, P. latipes ascends to the midlittoral zone in order to feed. Stomach fullness percentages indicated a higher feeding activity of this species in winter and spring than in summer and autumn. This is probably due to the necessity of accumulating energy resources for the spawning period, which begins in winter.