Reproductive cycle of Loligo sanpaulensis (Cephalopoda: Loliginidae) in the Cabo Frio region, Brazil

Gonadal index and maturity stages of the Brazilian squid Loljgo sanpaulensjs were analysed on a monthly basis. Squid were caught in coastal waters off the Cabo Frio region, Brazil, between 1987 and 1988 at depths rang~ng from 30 to 60 m using an otter trawl with 10 m footrope and 45 mm cod-end mesh size. Field data analysis showed that development of the nidamental gland and testis was closely related (r > 0.9) to body size and maturity stage in the population. Mature indiv~duals are recruited into the population twice a year. Size at first maturity was estimated to be 50 to 55 mm mantle length (ML) for males and 55 to 60 mm ML for females. Indirect evidence suggests that the final phases of the maturity process in females occur abruptly at some point after that size, and that recruitment of juveniles follows spawning and subsequent mortality or emigration of adults from the sampling area. Spawning is likely to take place in late summer and late winter