Social grooming is conspicuous in group-living mammals. Bats are gregarious and may groom each other, but the motivation for such social behaviour remains unclear. Here, we describe patterns and infer function of social grooming in tent-making Indian short-nosed fruit bats. Combining field and captivity observations, we found that males and their harem of females mutually groom and apply bodily secretions to one another in tight clusters. Mutual grooming is more commonly initiated by females, before emergence flight at dusk, and during the non-mating season. The within-harem association pattern suggests males may recognize female reproductive status via social grooming. Chemical analysis of the secretions applied during grooming revealed volatile organic compounds that may be involved in chemosensory-mediated communication and/or mate choice. These fruit bat harems were previously seen as simple aggregations, with limited interactions among individuals. Our findings suggest social grooming is multi-functional, with potential implications for the bats’ social lives.

<p>Excessive water loss during the day due to heat stress in bats of the genus <em>Pteropus</em> appears to be inevitable, because these bats are exposed to direct sunlight.  Rain also affects the rest pattern of the Indian Flying Fox <em>Pteropus giganteus </em>during the day.  When rain occurred during the day, most of the bats hung in a slanting position and did not exhibit any movements.  After rain, they licked both ventral and dorsal surfaces of the wing membrane and scratched their body with their thumb claws.  They also licked the water droplets that remained on the leaves and branches of the tree.  Even though their rest had been affected by the rain the bats utilized the water droplets to quench their thirst, cool their body and clean their fur.  The construction of water reservoirs near <em>Pteropus </em>roosts will help to assure their long-term conservation.</p><div> </div>

We studied wing loading of adult male (n=6) and female (n=5) of the Indian false vampire bat Megaderma lyra under seminatural conditions in an outdoor enclosure. Before releasing the bats into the enclosure, we measured their body mass, forearm length, wing area and wingspan. They were fed with frogs of four different categories of body lengths such as A = 3.0-3.5, B = 4.0-4.5, C = 5.0-5.5 and D = 6.0-6.5 cm. Bats were able to capture frogs A -C and carry them to roosts, that were at a height of 260 cm from the ground. However, when they captured frogs of the size D, most of the times they dropped the latter either after reaching the roost or even while carrying them. Alternatively, the bats carried the frogs (size D) but landed at a place (n = 30) closer to the ground and began consuming the prey. In general, greater the size of frogs, higher the wing loading of bats.

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