A Review of the Exotic Fishes in Arunachal Pradesh State, India

In order to cater high demand for domestic fish protein, many fast growing exotic fish species have been introduced for aquaculture in the last few decades, particularly in Arunachal Pradesh. Periodic surveys undertaken from 2015 to 2020 in different parts of the Arunachal Pradesh have revealed the presence of several exotic fish species in both natural and man-made water bodies. A total of 14 exotic fish species (belonging to 5 orders, 7 families and 11 genera) have been reported till now, and of these, 9 species are listed in Global Invasive Species Database of IUCN. Among the exotic species, 12 are listed in the Invasive Species Compendium of Centre for Agriculture and Bioscience International. Some of these have been introduced to the state officially for aquaculture purposes, others illegally or accidentally got entered in to inland waterbodies of Arunachal Pradesh. Introduction of exotic species without proper background research, especially in biodiversity rich areas is a threat to our native fish diversity. Exotic species may be considered responsible for negatively impacting native fish populations through predation, displacement, food competition, and may also cause genetic erosion. A timely intervention from state government, policy planners and organizations is urgently needed to check the activities of aquaculturists, ornamental fish traders and aquarium hobbyists who frequently breach the rules by bringing alien fish species into the state. An impact assessment study of invasive alien fishes on native fish biodiversity of the state is highly recommended.