Analysis of habitat-use using ordination: The Nilgiri tahr in southern India

摘要

Most conventional analyses relating to habitat use by large vertebrates are built on a univariate framework. Although they afford the major advantage of being simple to perform and interpret, they fail to take into account the interacting effects of multiple habitat variables on animal habitat use. Using data on the Nilgiri tahr (Hemitragus hylocrius), an endangered mountain goat of the Western Ghats, this paper presents a simple ordination technique, Principal Components Analysis, to analyse habitat use. We demonstrate that the distribution of all-male herds correlate with better foraging opportunities, and the distribution of female herds correlate with better security from predation. We also present an index to assess the relative importance of different variables in determining habitat use in the tahr. Finally, we encourage a wider application of such simple multivariate analyses in large animal ecology. [References: 13]