Modelling differential extinctions to understand big cat distribution on Indonesian islands

Abstract

ABSTRACT Aims To model differential extinction rates for island populations of tigers Panthera tigris and leopards P. pardus . Location Indonesia. Methods We built VORTEX population models of tiger and leopard populations on an island the size of Bali (3632 km 2 ), using data from the literature. Results The tiger populations were less extinction prone than the leopard populations. This was unexpected as tigers had the smaller population sizes and, as such, might be assumed to be more extinction prone. We identified several aspects of tiger breeding biology that explain the result. Main conclusions Sea level reconstructions suggest that both tiger and leopard would have been present in Java, Sumatra and Bali at the end of the last glacial. Our model provides a plausible mechanism based on population ecology to explain why these leopard populations were more extinction prone than the tiger populations. In addition it illustrates the potential utility of population ecology models in understanding historical patterns in biogeography.