Distribution, Abundance, and Habitat Signature of the Indian Giant Flying Squirrel Petaurista philippensis (Elliot 1839) in the Western Ghats, India

Abstract

The distribution and abimdance of the Indian Giant Flying Squirrel (IGFS) Petaurista philippensis, with respect to environmental variables, were investigated along the Western Ghats of Karnataka, Kerala, and Tamil Nadu. In Karnataka, a stretch of 1,582 km of forest trails and roads was sampled with spotlight searches between November 2001 and July 2004, while 127 and 133 points were sampled by the audio lure method in Kerala and Tamil Nadu respectively, between Jime 2005 and December 2008. Altogether, 418 individuals were recorded from 35 of the 38 forest stations sampled. The mean abundance of the IGFS was 0.187/km (± 0.234) in Karnataka, and 0.638/point (± 0.281) and 0.308/point (± 0.343) in Kerala and Tamil Nadu respectively. The southern distribution limit of the species in India was recorded as Kanyakumari Wildlife Sanctuary. Overall, the mean abimdance of IGFS was higher in the rainfed, mid-altitude slopes of deciduous and evergreen forests in Tamil Nadu and Kerala. Tree density, tree height, GBH (girth at breast height), canopy height and canopy cover were the key factors influencing the distribution of the species on the micro scale, while on the macro scale (home range) were the large extents of wet evergreen and moist deciduous forests. The study indicated that conservation of large trees with large trunk girth and thick canopy cover is necessary for the survival of the species in the Western Ghats.