An Overview on Fish Assemblages in Riverine Systems of Southern Bengal, West Bengal, India: Diversity, Distribution and Potential Threats

Abstract

West Bengal is a state in India well known for its topographical and biological diversity. The southern part of West Bengal has many rivers and rivulets, most of which are tributaries or distributaries of the Bhagirathi-Hooghly River. Rivers in Southern Bengal are now facing multiple problems, like water abstraction for irrigation, encroachment of the river bed, construction of dams and barrages, indiscriminate deforestation in the catchment areas, etc. Apart from indiscriminate fishing, increased proliferation of exotics, global climate change, fragmentation of habitat, and alterations in river hydrology are the major threats to fishes in riverine stretches of Southern Bengal. With the decreasing natural stocks and diversity of riverine fishes, the fisherfolk, depending on river productivity, are now facing severe problems in sustaining their livelihood. A rational management program for the rivers of southern Bengal should be put into place to protect fish diversity and increase fish production. The present review aims to provide a comprehensive picture of ichthyofaunal diversity, distribution and potential threats in riverine systems of Southern Bengal based on published literature in the form of research papers, books, monographs, and species inventories. This paper emphasizes the need for a regular exhaustive survey of ichthyofauna present in different rivers of Southern Bengal to create a comparable database that might be used for future research, planning, and management.