Roost tree characteristics of Pteropus medius (Chiroptera: Pteropodidae) in the midland laterite hillocks of northern Kerala, India

Abstract

The roost tree characteristics of Indian flying fox ( Pteropus medius ) were studied in the midland laterite hillocks of northern Kerala in peninsular India. A total of 170 trees belonging to 20 families, 32 genera, and 37 species were identified as roost trees from eleven roost sites located in Kannur and Kasargod districts of northern Kerala. Roost tree parameters such as habit, origin, diameter at breast height (DBH), tree height, bole height, crown length, crown spread, and crown closure were analyzed. Families Anacardiaceae and Lamiaceae represented more number of roost trees in the study area. The mean bat abundance per tree for the entire study area was found to be 54.35±5.2 and it was highest for Ficus religiosa (peepal) followed by Tetrameles nudiflora (false hemp tree) and Leucaena leucocephala (subabul) . Bats showed a preference for native trees and did not show any difference in the selection of evergreen and deciduous trees for roosting. The study also revealed that P. medius prefers large trees with greater height, diameter, crown length, and crown spread. As the midland laterite hillocks are under severe habitat degradation, the study recommends preserving large trees for better conservation of the remaining habitats of P. medius in the area.