TENT CONSTRUCTION BY THE SHORT-NOSED FRUIT BAT CYNOPTERUS SPHINX (CHIROPTERA, PTEROPODIDAE) IN SOUTHERN INDIA

The short-nosed fruit bar Cynopterus sphinx (Chiroptera: Pteropodidae) constructs shelters by severing stems of the curtain creeper, Vernoni a scandens, and stems and leaves of the mast tree, Polyalthia longifol ia, creating partially enclosed cavities (stem tents) in which to roos t. Our observations indicate that the construction and maintenance of stem rents are primarily, if not exclusively, the behaviour of single males. A stem rent is formed in V. scandens when a single male C. sphi nx severs up to 300 small- to medium-sized stems creating a partially flattened, bell-shaped cavity, and in P. longifolia when a male severs a few medium- to small-sized branches and many leaf petioles, creatin g an entry/exit portal and space in which to roost. A tent constructed in V. scandens is completed in approximately 30 d, whereas one in P. longifolia is completed in about 50 d. Stem-tent construction takes pl ace mostly at night, but some stem chewing occurs in late afternoon. A t night a stem tent is occupied by a single male, whereas females are usually absent. During the day the number of bats occupying completed tents is highly variable, ranging from two to 19 females (and their pu ps) and a single adult male. Tent construction is annually bimodal, wh ich corresponds to a biannual breeding season. A dominant male sometim es deposits saliva on branches inside his rent cavity and actively def ends this space from intrusions by other males. Both behaviours sugges t forms of scent marking and territorial display. Our observations ind icate that dominant males construct tents, recruit females and then de fend the tents (and their female occupants) for the purpose of gaining reproductive access. The variance in harem group size indicates that some tent-making males are more successful than others in recruiting f emales.