Pradip Kumar Sarma, Gaurab Jyoti Kalita and Nripendra Nath Sarma
The present work was carried out in the rivulet Bishan Nalah of Barpeta District of Assam, which lies between 26° 28’ 00’’ North latitude; 91° 10’ 00’’ East longitudes , during the period of two consecutive years from December, 2012 to November, 2013. Altogether 85 species of fishes are diversified over 6 orders, 28 families and 55 genera. Dumping of garbage, drainage of sewage and waste product, construction of number of bridges, impeachment on both side of the bank, soil erosion, siltation, eutrophication, high infestation of macrophytes, over exploitation, operation of fishing gear and flow of effluents into the water bodies are the major factors for the declining of present fish diversity
