Mean length at first maturity of the spiny I lobster Panulirus laevicauda (Latreille) off Ceará State, Brazil

Abstract

Through samplíngs accomplished on board medium-sized commercial boats operating in depths from 10 to 90 meters on the continental shelf off Ceará State, Brazil, 13,921 females of lobster Panulírus laevicauda were examined and measured in the period from January, 1984 to December, 1993. From the sampled females the gonads were drawn for characterization of the macroscopic aspects of sexual development. The data analysis showed there to occur a lesser or larger incidence of juveniles or adults in relation to depth of the sampling site. The mean length at first sexual maturity was influenced by the proportion of juveniles in the catch. For the effect of stratification to be lessened, the mean size at first maturity was obtained from data of the whole studied period. The cape size at which 50% of the females are expected to be spawning in the population is 63 mm.