FISH DIVERSITY OF KUSHIARA RIVER AT MONUMUKH POINT: PRESENT STATUS AND FUTURE PROSPECTS

Abstract

River Kushiara is a momentous and eminent river in the greater Sylhet region of Bangladesh. The study was conducted for one year from July 2013 to June 2014 to assess the present status of diversity of fish fauna and water quality parameters of Kushiara River at Monumukh point. A total of 58 fish species including 26 threatened species and 6 exotic species were documented from the study. Cyprinidae was recorded as the most diversified fish family comprising 14 species followed by 6 species of bagridae and 5 species of schilbeidae. The highest number of species was Puntius ticto (5.37%) followed by Amblyopharyngodon mola (4.82%) and Mystus tengra (4.78%). Among the identified fish species 44.63% was recorded as threatened according to IUCN and 5.49% was exotic species in respect of number. The seasonal highest catch 1991.54 kg was recorded in the winter and the lowest 558.671 kg in the summer. The value of diversity index ranged from 3.446 (Summer) to 3.676 (Monsoon), richness index ranged from 6.41 (Winter) to 5.536 (Summer) and evenness index ranged from 0.903 (Postmonsoon)

to 0.948 (Monsoon). Significant environmental parameters such as temperature, turbidity, TDS, total hardness pH, dissolved oxygen, CO2, NH4 (ammonia), chloride and nitrite were evaluated during the present study. All the water quality parameters found within the permissible limits for fisheries. In conclusion, bearing all the outcomes found in the study indicates that the Monumukh Point of Kushiara river is enriched with fish diversity including threatened fish species of Bangladesh which demands the conservation of the area as a natural gene bank immediately. Besides, existence of exotic species indicates potential threats to indigenous species in future in the river system of the Kushiara.