Reproductive biological traits of the goby Stigmatogobius pleurostigma (Bleeker, 1849) from the Mekong Delta, Vietnam

Abstract

Stigmatogobius pleurostigma (Bleeker, 1849) is an estuarine species of goby and widely distributed in Asian regions, but very little is known about the reproductive biological traits of this species. The present study was conducted along the coastline of the Mekong Delta, Vietnam from November 2015 to October 2016 to elucidate basic reproductive parameters of the species. A total of 155 fish (96 females and 59 males) were collected every month using fixed bag nets from the mangrove forests in the study area. Data analysis showed that the sex ratio is significantly different from 1:1. This gobiid species is an iteroparous fish spawning from March to November in the study region as deduced from the appearance of mature and ripe ovaries during this period. The length at first maturity was estimated as 4.14 cm in total length and absolute fecundity was found to be quite high (3,100-5,650 eggs) with a strong positive relationship with fish length and weight. The results obtained in this study contribute to the knowledge on the reproductive biology as well as stock status of the species.