Roosting habits and habitats of the Indian Flying Fox Pteropus medius Temminck, 1825 in the northern districts of Tamil Nadu, India

Abstract

This paper pertains to the study on roosting habits and habitats of the Indian Flying Fox Pteropus medius Temminck, 1825 in 12 villages of four northern districts—Vellore, Krishnagiri, Tiruvannamalai, and Viluppuram—of Tamil Nadu. Studies targeted roosting tree species, population status, diurnal-roosting behaviour, interactions with other animals, and probable threats to the species. A total of 22,365 individuals of the species were observed in 72 roosting colonies in 72 trees belonging to nine families, 11 genera, and 13 species. The tree species that harbored the greatest population of P. medius (n= 12,465) were those of Tamarindus indica L. (Fabaceae) (n= 39), followed by Ficus religiosa L. (Moraceae) (n= 3,960), Madhuca latifolia J.F. Macbr. (Sapotaceae) (n= 2,760), and Ficus benghalensis L. (Moraceae) (n= 1,620). One-Way ANOVA revealed that a significant relationship exists between\xa0 colony size and tree diameter at breast height (dbh), and their canopy size (p <0.05). However, no significant difference occurred between the colony size and tree height. The time taken for emergence of individuals of the colony from the canopy for foraging varied between 20 and 40 min after 1750 h in the evening. The species mostly roosted on trees proximal to human settlements, electrical power lines, and water bodies. Individuals of P. medius used various tree species in different areas in different geographical regions and did not maintain any consistency in roosting tree species selection. A majority of individuals (88.7 %; n= 887) were found roosting using both legs and a minority of P. medius (11.3 %; n= 113) were clinging to tree branches using one. Individuals of P. medius flew to nearby water bodies to quench thirst and cool their bodies. Mating was observed during day roost in 146 pairs including male-female fellatio in seven pairs. Smoke from shrines in sacred groves, pruning of branches for various cultural reasons, populations of House Crow Corvus splendens (Vieillot, 1817) (Corvidae), Black-winged Kite Elanus caeruleus (Desfontaines, 1789) and Black Kite Milvus migrans (Boddaert, 1783) (both Accipitridae) were key disturbances to roosting populations of P. medius.