Fish Biodiversity Status in The Kobadak River of Bangladesh: Present Status, Threats and Conservation Perspectives.

This study assessed the status of fish biodiversity in the Kobadak River basin of Tala Upazila, Satkhira, Bangladesh, from January to June 2024 at four locations. A total of 12,040 fishes (belonging 34 species, 19 families, and 9 orders) were identified, and data was collected through a structured questionnaire. The Shannon-Wiener Index and Simpson's Index showed moderate to high species diversity and richness in the river basin, with values of 3.20-3.45 and 0.80-0.96, respectively. The findings indicated a moderate to high diversity, with Cypriniformes dominating (40.39%), followed by Perciformes (30.66%) and Siluriformes (21.68%). The most abundant species were Labeo rohita and Catla catla, while the least abundant Chitala chitala and Notopterus notopterus. Conservation status indicated that 58.82% of species are least concern, 23.53% near threatened, and 17.65% vulnerable. This research emphasized the ecological importance of the Kobadak River's fish diversity and the necessity for sustainable management to protect its fish populations.