Food and feeding habits of grizzled giant squirrel (Ratufa macroura) at chinnar wildlife sanctuary, western ghats, Kerala

Abstract

The research work entitled “Food and feeding habits of Grizzled Giant Squirrel (Ratufa macroura) in Chinnar Wildlife Sanctuary, Western Ghats, Kerala” was carried out in five locations namely Chinnar, Kootar, Chambakkadu, Athiyoda and Alampetty in the Chinnar Wildlife Sanctuary. The main objective of the study was to find out the food and feeding habits including the food preferences and time activity budgeting of Grizzled Giant Squirrel. Apart from that an attempt has been made on the population estimation of the Grizzled Giant Squirrel and also the habitat quality analysis. Focal animal sampling method across different season was deployed to gather information on food species and article preference, feeding habits, seasonal variation in feeding and the time activity budgeting. Besides these, the population density of the squirrel was estimated by direct observation through line transect method. The indirect population estimation and quality of available habitat was estimated through drey (nest of the squirrels) analysis. The vegetation within the Grizzled Giant Squirrel habitat was studied using quadrate method and Important Value Index. The Grizzled Giant Squirrel in Chinnar Wildlife Sanctuary found to be feeding on 30 plant species. The squirrel's preference for diet was found primarily affected by availability of food tree species and food article rather than the season. The climbers, lianas, shrubs and cactus also formed the part of squirrel’s diet. It is for the first time that non-tree elements have been reported from the diet of Grizzled Giant Squirrel. The Grizzled Giant Squirrel has been primarily a frugivorous animal, but at the time of the non-availability of fruits and seeds they fed on leaves, flowers and bark. The Grizzled Giant Squirrel in Chinnar Wildlife Sanctuary was found to be spending most of its time on feeding followed by resting, moving and calling. The animal was found to be using 48 tree species at Chinnar Wildlife Sanctuary, of which 22 tree species were used for feeding, 36 tree species were used for drey construction, while ten tree species were used for both feeding as well as drey construction. The population size of the Grizzled Giant Squirrel was estimated to be 30-35 individuals. This is considerably fewer than the earlier population estimates of Grizzled Giant Squirrel at Chinnar and is a matter of concern. The major threats of Grizzled Giant Squirrel at Chinnar Wildlife Sanctuary were anthropogenic disturbance, habitat loss, predation and hybridization. The Grizzled Giant Squirrels’ preference for bigger and taller trees for drey construction indicates the significance of presence of mature forest trees with canopy continuum for long-term survival of squirrel at Chinnar Wildlife Sanctuary.