Ant Diversity along an Elevational Gradient in Champadevi Hill,Central Nepal

Abstract

Nepal is characterised by high floral and faunal diversity but there are limited studies about ants. The present study is aimed at exploring the ant diversity along an elevational gradient (from 1450 m to 2452 m) in the north and south slopes of Champadevi hill, central Nepal. Ant samples were collected by using pitfall traps and all-out-search methods from spring to autumn in 2017. To find the determinant relationship between ant species richness and environmental variables (elevation, seasons, aspect, disturbance and vegetation canopy), a generalized linear model (GLM) with Poisson distribution and log link function was used. Multivariate tests for the composition of ant communities were carried using a unimodal technique known as Canonical Correspondence Analysis (CCA). Six subfamilies and 33 genera were recorded from the study. Species richness decreased with increasing elevation. The species richness was maximum during spring season (n=12) than in autumn season (n=5) and it was higher in the northern aspect (n=29) than the southern aspect (n=25). Ant composition was affected by elevation (p=0.004), seasons (p=0.002) and aspect (p=0.002). Disturbance (p=0.054) and canopy cover (p=0.180) do not show a significant effect on composition. Amblyopone and Ponera were found as new genera to Nepal. The high diversity of ants in our study area showed that the systematic study could lead to the recording of more species in Nepal.