Aspects of the Fishery and Reproduction of Nematopalaemon hastatus (Crustacea: Palaemonidae) in the Cross River Estuary, Nigeria

Abstract

The fishery and reproductive cycle of Nematopalaemon hastatus, the species on which the artisanal shrimp fishery in the Cross River estuary is based, was investigated over a 14-month period. The mean catch composition (by weight) was 70% N. hastatus, 14% Parapaeniopsis atlantica, 3% Exhippolysmata hastatoides, and 14% bycatch. The catch per unit effort peaked in May and November at the beginning and end of the rainy season, although there was no correlation between CPUE and rainfall. The species breeds throughout the year but with peaks in June and November. At the major breeding peak in November about half of the total numbers of N. hastatus were gravid females. The significance of this and the trends in variation of CPUE are discussed.

Key words: estuarine fishery, catch composition, catch rate,spawning, Nematopalaemon hastatus