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Prey signalling in aggregation become more conspicuous with increasing numbers and tend to attract more predators. Such grouping may, however, benefit prey by lowering the risk of being captured due to the predator's difficulty in targeting individuals. Previous studies have investigated anti-predatory benefits of prey aggregation using visual predators, but it is unclear whether such benefits are gained in an auditory context. We investigated whether katydids of the genus Mecopoda gain protection from their acoustically eavesdropping bat predator, Megaderma spasma, when calling in aggregation. In a choice experiment, bats approached calls of prey aggregations more often than those of prey calling alone, indicating that prey calling in aggregation are at higher risk. In prey capture tasks, however, the average time taken, and the number of flight passes made by bats before capturing a katydid, were significantly higher for prey calling in aggregation as compared to calling alone, indicating that prey face lower predation risk when calling in aggregation. Another common anti-predatory strategy, calling from within vegetation, increased the time taken by bats to capture katydids calling alone but did not increase the time taken to capture prey calling from aggregations. The increased time taken to capture a prey calling in aggregation compared to solitary calling prey offers an escape opportunity, thus providing prey signalling acoustically in aggregations with anti-predatory benefits. For bats, greater detectability of calling prey aggregations is offset by lower foraging efficiency, and this trade-off may shape predator foraging strategies in natural environments.

A study was conducted on the diversity of butterflies by using the pollard walk method in the tropical dry deciduous habitats of Shettihalli Wildlife Sanctuary, Shivamogga District, Karnataka, from February 2010 to January 2011.  A total of 151 species of butterflies belonging to 99 genera and five families was recorded. The family Nymphalidae was the most dominant with the highest number of species (52 species; 35%), followed by Lycaenidae (33 species; 22%), Hesperiidae (25 species; 17%), Pieridae (24 species; 16%), and Papilionidae (15 species: 10%). The study also revealed 24 species of butterflies which are protected under various schedules of Indian Wildlife Protection Act, 1972, and 13 species as being endemic to the Western Ghats, peninsular India and Sri Lanka.

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