Reproductive period and weight/length relationship of two Astyanax species (Pisces, Characidae)

Abstract

The reproductive period of Astyanax fasciatus and A. bimaculatus of Broa Reservoir, in São Paulo State, Brazil, was determined by the variation of the relative frequency of the maturity stages (2. Adult in reproduction, 3. Adult that is not in reproduction), the variation of the average grade of maturation (Gm) and the average gonadossomatic index (Ig). The weight/length relationship was established by the expression: W_t = ø L_t^Θ, where ø is the condition factor related to the fatness and Θ a constant related to the growth of the individual.