Studies on biodiversity and abundance of fishes in floodplain of Bangladesh

Background/Question/Methods

Biodiversity or biological diversity has assumed topical significance in recent times. Quantification, conservation and rational utilization of biodiversity hold the keys for sustainable development, especially in the thickly populated third-world countries. The present investigation discloses the outstanding richness and diversity of the fish fauna of three flood plain beels namely Boro beel, Borobila beel and Gawha beel of Bangladesh. Measuring biodiversity of fishes the Shannon weaver index was used to measure the extent of diversity by combining aspects of species richness and evenness of fishes.

Results/Conclusions

A total of 72 species of fish and prawns belonged to nine orders 24 families and 53 genera were recorded from the Boro beel. Out of 70 fish species were 64 indigenous and 6 exotic species, and remaining two were prawn species. Among these species, Cyprinidae dominated with 21 species (including five exotic species) followed by Bagridae with seven species, Schilbeidae with five species, and Osphronemidae and Channidae (Ophiocephalidae) each with four species, and Ambassidae, Clupeidae and Mastacembelidae representing three species each. In the case of Borobila beel, altogether 58 species of fish and prawns represented eight orders, twenty families and 41 genera were recorded during the study, out of which 57 were fish species (52 indigenous and 5 exotic species) and remained one was prawn. Cyprinidae was found to be dominating family (19 species) followed by Bagridae with seven species, and Channidae (Ophiocephalidae)  and Osphronemidae each contained four species, and Ambassidae and Mastacembelidae having three species each. Cobitidae, Siluridae, Schilbeidae and Tetradontidae contained two fish species each and remained ten families with one species each. Study revealed that the presence of 38 species of fish belonged to six orders, 17 families and 28 genera in the Gawha beel. Out of 38 fish species 33 were indigenous and five exotic species. Cyprinidae dominated the fish communities with 14 species (including the five exotic species) followed by four species of Bagridae and Ambassidae and Mastacembelidae each contained three species and Channidae having two species.A total of 75 fish species belonged to 23 families were also recorded from different Indian water bodies. Considering the species diversity and abundance, the floodplain beels to be preserved for conservation of fish faunal diversity and the nutritional security of the peoples of developing and under developed countries.