Resource availability,within-clan and between-clan agonistic interactions, and dominance relationships amongst female Asian elephants in Nagarahole national park,southern india

Abstract

Socioecological theory is a broad framework that attempts to explain the variation in sociality amongst animals in terms of responses to resource-risk distributions (for example, Crook and Gartlan 1966, Alexander 1974, Wrangham 1980, Terborgh and Janson 1986). The ecological model of female social relationships (EMFSR, Koenig et al. 2013), which is part of socioecological theory, posits that predation and food characteristics shape female social organisation by making dispersal risky and determining the strength of scramble and contest competition within and between groups (Wrangham 1980, van Schaik 1989, Isbell 1991, Wrangham et al. 1993, Isbell and van Vuren 1996, Isbell and Young 2002, Sterck et al. 1997). Assessments of the abundance and distribution of resources, feeding competition, and social relationships between individuals are required in order to test predictions from the ecological model of female social relationships. A vast majority of the studies on socioecology have been carried out on primates (for example, Chapman et al. 1995, Koenig and Borries 2006, Snaith and Chapman 2007, Chancellor and Isbell 2009, Grueter et al. 2016, Teichroeb and Sicotte 2018, apart from the references mentioned above) and studies of the EMFSR on other taxa are required (Clutton-Brock and Janson 2012). In this context, I examined the relationship between food resources and within- and between-group contests in a non-primate species, the Asian elephant (Elephas maximus), feeding primarily on grass, traditionally thought of as a low-quality resource, in Nagarahole National Park and Tiger Reserve, southern India. This thesis is divided into two parts: 1) assessment of methods to estimate forage abundance for Asian elephants, and 2) investigation of the influence of ecological variation on contest competition within and between groups of female Asian elephants, and the social and foraging consequences of dominance interactions. Since it is important to measure resource abundance when examining the EMFSR but resource abundance is also difficult to directly measure for elephants and has rarely been done before, the first two data chapters deal with issues related to such measurements.