The intraspecific and spatio-temporal changes in growth pattern and condition factor of Glossogobius aureus inhabiting in the Mekong Delta, Vietnam

The present study was conducted in four sampling sites, from fresh to brackish waters, to contribute knowledge on the length-weight relationship, growth, and body condition factor of the commercial fish Glossogobius aureus (Gobiiformes: Gobiidae) in the Mekong Delta. Fish specimens were caught using gill nets from January to December 2020. Data analyzed results of 742 specimens (382 males and 360 females) showed that weights of males and females in various sizes, seasons, and sites are able to estimate from a fish given length due to high determination coefficients (r²> 0.8, in all cases). The growth pattern of Glossogobius aureus fluctuated monthly from negative allometry to isometry and positive allometry as its slope (b) obtained from LWRs ranged from 2.583±0.119 SE to 3.123±0.066 SE. Likewise, b of this fish changes with fish size and site, but not season and gender. Albeit the growth pattern showed intraspecific and spatio-temporal variations, this goby displayed negative allometry since b (2.859±0.030) was lower than three. Likely, fish body condition factors, ranging from 0.937±0.022 SE to 1.218±0.030 SE, varied between fish sizes, sites, and months. The present findings contributed valuable data to understand fish adaptation and fishery management.