Ichthyofaunal diversity of Boro beel, Pabna, Bangladesh

Background/Question/Methods
The fish biodiversity of Bangladesh is ranked as the third largest in Asia after China and India. Bangladesh is endowed with vast inland fishery resources of which beel fisheries are of prime importance having a great potential to enhance the inland fish production several fold. Beel fisheries are an important source of animal protein and livelihood for their population. The extreme population density of Bangladesh puts major pressures on the beel resources, directly through resources over-exploitation, and indirectly through changes in habitat quantity and quality. Aiming at preparation of a complete list of fishes along with a quantified and categorized list of indigenous species of Boro beel. Boro beel is open beel located at Pabna District in Bangladesh. The approximate water area during rainy season is 3,000 ha and that during dry season is 300 ha. Water depth varies from 1.0 meter to 5.0 meter.

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 each belonged four species, and Ambassidae, Clupeidae and Mastacembelidae representing three species each. Prawn (Macrobrachium spp.) was found to be dominant form in numerical abundance composition of fish and prawn assemblage by their common groups in beel. In terms of weight composition (% wt.), minnows and carps were dominating common fish guilds recorded in the study period. Overall, Puntius sophore was found to be the most dominant species in respect of weight abundance (%). A total of 39 species of beel resident fish and prawn, 18 species of migratory fish and prawn, and 9 species of riverine fish and prawn were recorded. Mystus tengara showed numerical dominancy (% number) among resident fish communities, whereas P. sophore (21.85%) were found to be the most dominating resident fish species in biomass abundance (% wt.). Corica soborna showed highest numerical abundance among riverine fish and prawn communities. Results of the present study indicated that small fish and prawn species form major portion of capture fisheries in Boro beel. The findings of this study are expected to provide baseline information on biodiversity for sustainable management of beel resources.