Gonadosomatic Index (GSI) of Sardinella lemuru from Pantukan, Davao de Oro

Abstract

This study investigates the gonadosomatic index of Sardinella lemuru, a commercially important species inhabiting highly productive marine environments. Despite its economic and ecological value, there is limited information on the reproductive biology of this species, particularly concerning the gonadosomatic index, which is essential for understanding reproductive cycles, population dynamics, and effective fishery management. Samples of Sardinella lemuru were collected across two time points, and the index was measured to evaluate temporal patterns in reproductive development. Several individuals displayed values consistent with previous estimates for fecundity, suggesting advancing reproductive maturity during the observed period. The observed increase in gonadosomatic index values between sampling points may indicate progression toward a spawning phase. Linear regression analysis revealed a statistically significant positive relationship between body weight and gonad weight, suggesting that somatic growth influences reproductive investment. These findings highlight the reproductive potential of Sardinella lemuru and its relevance for aquaculture and fisheries sustainability. Future research should expand the sample size and extend the observation period to improve accuracy and consider additional factors influencing reproductive traits, including fecundity.

Keywords: Body weight; gonadal development; reproductive biology; sardine species; spawning potential