1. INTRODUCTION

The ecological role of an animal in an ecosystem can be revealed by understanding its diet and feeding behaviour (Bookhout, 1994; Dell’Agnello et al., 2019). The feeding behaviour might be specific to the place where an animal lives. It influences all the decisions of the animal about food resources available along with predator avoidance strategies (Pyke, 1984; Sih, 1980). Feeding has a considerable impact on animal fitness through its effect on animal growth, survival, activity patterns and reproductive ability (Foley & Cork, 1992; D. Raubenheimer & Simpson, 1997; David Raubenheimer et al., 2015), thus it is an important aspect of animal conservation. The availability of food in an area is vital in supporting a minimum viable population for the animal to thrive (Palmer & Koprowski, 2014). The variation in food availability by the seasonal fluctuation can challenge the animal to meet its requirements. Seasonal shift or facultative adjustment in food material preference gives an animal large dietary breadth and flexibility to cope with situations of resource scarcity (Dunn et al., 2010; Masi et al., 2015).
Herbivorous mammals may impact the plant resources near its foraging sites either negatively or positively and can affect the composition and structure of plant communities (Olff & Ritchie, 1998; Palmer & Koprowski, 2014). Small mammalian herbivores, such as rodents, modify their environment by consuming plant biomass and redistributing materials across the landscape (Moorhead et al., 2017). In particular, small mammals can stimulate soil nutrient cycling through the faecal deposition (Bakker et al., 2004). Tree squirrels (order Rodentia) are cosmopolitan in distribution on almost every continent except Australia and Antarctica (Koprowski & Rajamani, 2008; Thorington Jr et al., 2012) and play key ecosystem services, including seed dispersal and pollination (Miyaki, 1987; Steele et al., 2005; Zong et al., 2010). The giant squirrels are tree squirrels and the largest in the world, and they belong to the genus Ratufa (Thorington & Cifelli, 1989).
The Grizzled Giant Squirrel (hereafter GGS) belongs to the genusRatufa , has three distinct subspecies and India harbour only one,Ratufa macroura dandolena and it is one among the other three species of the giant squirrels in India (Ellerman, 1961; Johnsingh & Nameer, 2015; Menon, 2014). This Near Threatened squirrel is primarily diurnal, but their increased activity has been observed during the early and late hours of the day (Paulraj, 1991). The GGS shows one of the most important examples of isolated populations, and the habitat of the animal is extremely unique and is confined primarily to a narrow stretch of riparian vegetation along the Pambar and Chinnar rivers and their major tributaries in the Chinnar Wildlife Sanctuary (Ramachandran, 1993), in the southern Western Ghats. In India, Chinnar Wildlife Sanctuary in Kerala supports the second-big population of GGS. To protect and improve the conservation measures directed to an animal, especially a habitat specialist like the GGS, a proper understanding of the habitat requirement is vital (Mills, 1992). We focused on the foraging ecology of the GGS, to understand the seasonal variation in food preference, food composition and feeding technique. The diet and feeding behaviour of the GGS is not well known so far thus, it would help in making specific management prescriptions for protecting the Near-Threatened GGS in one of its prime refugia in India.