RELATIONSHIP BETWEEN FECUNDITY AND BIOMETRIC INDICES OF THE WEST AFRICAN BONGA SHAD (Ethmalosa fimbriata) FROM THE CROSS RIVER ESTUARY, NIGERIA

Abstract

Biometric data such as length–weight relationships and condition factor are veritable tools in fisheries management as it provides information about fish growth, wellbeing, and reproductive fitness. This study assessed the fecundity and biometric relationships of African Bonga Shad (Ethmalosa fimbriata), a key species in West African estuarine fisheries that supports artisanal livelihoods and food security. A total of 160 specimens were collected monthly from February to May 2021 from Ikang and Nsidung beaches in the Cross River Estuary and analysed following standard laboratory procedures. Fecundity ranged from 5,720 eggs in fish of 17.5 cm SL and 180 g body weight to 114,400 eggs in fish of 30.0 cm SL and 550 g. Fecundity showed significant positive relationships with standard length, fork length, total length, total weight, ovary weight, and gonadosomatic index. Ovary weight was the best predictor of fecundity. These findings improve understanding of the reproductive potential of E. fimbriata in a tropical estuarine ecosystem and provide useful information for predicting its breeding season. This is important for sustainable harvest regulations, protection of spawning biomass, and ensuring the long-term availability of this widely consumed species that contributes to regional nutrition and food security.