The northern part of the state of West Bengal, particularly the Himalayan range has been bestowed with a great wealth of perennial rivers and small streams. These rivers and tributaries, namely, the Teesta, Rangeet, Ralli, Rishi, Reyang, Gelkhola Pala, Mahananda , Balasun and others are sources of important sport & ornamental fish species, crabs & prawns which have high export value. These precious species have never been investigated properly nor have they been identified for commercial purposes Moreover, the number of indigenous, flora and fauna is declining every year due to the various man made and natural calamities. Moreover, a number of mini hydroelectricity dams are under construction across the river Teesta that will further add to the decline of various fish species. There is no substantial data of cold-water fisheries to come up with credible information to provide a firm base for formulating suitable guidelines for conservation, propagation and judicious exploitation of the existing resources of the cold-water fisheries in the state of West Bengal. For the last decade, the Department of Fisheries, Aquaculture, Aquatic Resources and Fishing Harbours, GOWB, with the collaboration of DGHC is coming up with numbers of fishery projects for sustainable utilisation of its vast resources and playing a vital role towards the upliftment and shaping of the socio-economic condition of the people of this region. A detailed survey on the water quality, fish species diversity of the North Bengal with special emphasis to cold water fisheries is therefore important for propagation and conservation of the important flora and fauna of this region in order to come up with proper planning for sustainable exploitation without disturbing the natural eco-system. Hence an attempt has been made in this book to assess the resource inventory of cold water fisheries, to study the growth, food, feeding habit and viability of coldwater fish species in confined water, to assess the constraints of implementing coldwater fishery and to survey the present fisheries scenario of North Bengal and measures to be taken in a systematic manner.