Fisheries resources of India are highly diversified in type and nature. Nearly 22,000 species of finfishes are known world-wide.
About 10% (2,200 species) of the global fish diversity is found in Indian waters. Out of these, about 400 species are commercially important which include cultured, cultivable and wild species, however, only few are being presently utilized in aquaculture. These fishes have acquired a wide variety of forms and habitats which have been reflected in their adaptations to survive in markedly varying biotypes, ranging from cold torrential mountain streams to the dark byssal depth of the seas. Too many facors are having their impacts on fish gemplasm. Fish genetic resources, especially in the developing countries like India are under harsh
environment attributable to the multipronged degradation which may be due to over exploitation or water
pollution or habitat shrinkage. As a result some of the prime fish germplasm are either depleting or gradually declining day by day. Factors responsible for habitat shrinkage are industrialization, urbanization and over harnessing of aquatic resources for commercial purposes. It includes impoundment of lotic eco-system, destruction of luxuriant flora in the catchment area, reclaimation of wetland for agriculture and allied activities, layout of roads along the river courses, natural calamities like prolonged drought can destruct the aquatic diversity to a great extent. Introduction of genetically modified organisms or introduction of exotics is also threatening the aquatic biodiversity to a large extent. Overexploitation of natural resources is already imparting tremendous pressure on natural resources. In fisheries sector overexploitation and destructive fishing by using small sized nets, ghost fishing by using dynamite, poisons, etc. are eliminating fish germplasm rapidly. Increasing pressures on aquatic resources dictate that fish conservation can no longer be treated in isolation and an integrated approach to aquatic resource management is required.