Some biological characteristics of broadhead sleeper (Eleotris melanosoma) distributed in Thi Nai lagoon, Binh Dinh province
Abstract
Broadhead sleeper ( Eleotris melanosoma ) is one of goby species inhabited in Thi Nai lagoon - Binh Dinh province which is seriously affected by the exploitation, however there is no study conducted on this species.Some biological characteristics of broadhead sleeper were examined from August 2018 to January 2019. Fish samples were collected every month and their characteristics on feeding, growth and reproduction were examined. The results showed that morphological characteristics of digestive system of fish such as sharp teeth, clear stomach or short intestine indicated carnivorous feeding of this fish. The relative length of the gut (RLG) of fish was from 0.8 to 0.81. The composition of natural food of this fish included mollusc, crustacean and fish, with the occurrence frequency of 95.17%, 4.83% and 1.86% respectively. There was a high correlation between length and weight of gobies, with R 2 = 0.9447, and the relationship between these two parameters was expressed by the equation W=0.0054L 3.3223 . The spawning season of this goby species could be from October to December that was based on GSI and HSI recorded. The results collected from this study indicate that b roadhead sleeper is carnivorous fish species and their spawning season in Thi Nai lagoon is concentrated in rainy months.