Population structure and reproductive parameters of the cassava croaker, Pseudotolithus senegalensis (pisces, valenciennes, 1833) in nearshore waters of benin (West Africa) and their implications for management

The production of the common commercially Sciaenids species, Pseudotolithus senegalensis off Benin nearshore waters, has been decreasing since 1994, and increasingly more small-sized fishes are regularly harvested, while very little information exist about the species’ population structure and life history. Therefore, population structure, probability of capture and size at first capture were investigated using length-frequency data of 865 specimens sampled from beach seine hauls over a period of 18 months. A total of 51.23% of this population were immature, confirming the domination of small-sized fishes in the catches. Gonad maturation stages were also examined. Histological structure of ovaries and frequency distribution of oocyte size exhibited two cohorts of mature oocytes suggesting two spawning periods per year. Monthly averages of gonado-somatic index confirmed that P. senegalensis spawned twice a year during the major warm season (March – May) and during the transition minor warm to minor cold season in October –December. Length at first capture was greater than the length at first sexual maturation indicating minimal pressure of the beach seine gear on this resource. Innovative and precautionary management measures involving all relevant stakeholders in a community-based management effort to reduce fishing pressure during the reproductive periods from March to May and from October to December yearly.