SEX-DIFFERENCES IN RESOURCE UTILIZATION BY THE PEACOCK BLENNY

This paper presents data on the seasonal variation of gonadosomatic, h epatosomatic and feeding indices in nesting males, females and female- like males of the blenniid fish Salaria pave. Eviscerated condition fa ctors, female fecundity and feeding rates are also presented. The resu lts are consistent with the hypothesis that females maximize their fee ding rates during reproduction, converting food into eggs through repe ated spawning. Nesting males feed at a very low rate during the breedi ng season. It is argued that one major component of the reproductive c osts in these males is the reduction of feeding opportunities. Female- like males present lower reproductive costs, which probably reflects t he compromise between fertilizing some eggs and growing. (C) 1997 The Fisheries Society of the British Isles.