Ichthyofaunal Diversity Correlates Hydrological Parameters in Wetlands of Nameri National Park and its Adjacent Area, Assam, India

Abstract

Excessive anthropogenic activities such as heavy fishing, the fish fauna in northeast India has been declining at a rapid rate. The wetlands in Nameri National Park (NNP) witness the severe decline of fish fauna due to overfishing and human interference in the buffer zone. The present study has been carried out from May 2017 to April 2019 in 12 random sampling sites. A total of 79 fish species were recorded belonging to 6 orders and 24 families. The order Cypriniformes was found to be dominant with 44 fish species followed by Siluriformes with 18 species, Perciformes with 11 species, Synbranchiformes with 4 species, and Beloniformes and Cluepiformes with one species each. The Shannon-Wiener diversity index (3.81), Margalef richness index (8.07), Pielou’s evenness index (0.59) was high, while Simpson dominance index (0.02) was low in the pre-monsoon season, which indicates that during pre-monsoon the fish diversity has been highest than the other seasons of the year. As far as biodiversity status (IUCN Status) is concerned, 78.48% Least Concern (LC), 3.79% Data Deficient (DD), 5.06% Not Evaluated (NE), 7.59% Near Threatened (NT), 2.53% Vulnerable (VU) and 2.53% Endangered (EN) respectively. However, two vulnerable and endangered species have been found during the survey.