Population density and nesting behaviour of Indian Giant Squirrel Ratufa indica (Erxlebeln, 1777) in Bhimashankar Wildlife Sanctuary, Western Ghats of Maharashtra, India

Abstract

The Indian Giant Squirrel Ratufa indica (Erxlebeln, 1777) has been officially designated as Maharashtra’s state animal. It is restricted to the eco-sensitive Western Ghats region and is currently classified as Least Concern species on the IUCN Red List. However, the species is dependent on intact habitat and is negatively impacted by habitat fragmentation. Population density and nesting behavior were studied in a major habitat in the tropical semi-evergreen and evergreen forest of India’s Bhimashankar Wildlife Sanctuary. Two-hundred-and-twenty-three direct sighting along 60 km line transects were used to estimate squirrel density. It averaged 13.9±0.18 squirrels/km2. Nesting characteristics were evaluated using 4,224 nests. The squirrel uses 52 different tree species for nesting, with Mangifera indica (15.57%), Olea dioica (14.65%), and Mallotus phillippensis (9.78%) being the most popular. The drays were found on trees that are taller than average, have a massive girth at the breast height, and have continuous closed canopies. To avoid predators, Indian Giant Squirrels usually flee to the nearest adjacent tree.