The Effect of Seasonal Changes on Emergence Behaviour of the Indian Flying Fox, Pteropus giganteus

The emergence behaviour of the Indian flying fox, Pteropus giganteus in response to different seasons and environmental conditions was studied in an age-old colony located at Mohanlal Ganj, Uttar Pradesh, India. The bats were chosen large, tall and well exposed Eucalyptus sp. trees as their roost. The behavioural activities such as wing stretching, shifting of roost to the periphery, vocalization and circling flights around the roosts were initiated by a few individuals before their emergence. The average bat emergence was observed 0:32 ± 0:10 h:min after the sunset and varied over seasons. The time of bat emergence was significantly influenced by the day length (r = 0.889), sunset (r = 0.952) and the ambient temperature delayed the time of emergence (r = 0.886). The duration of emergence was relatively short during winter compared to summer and monsoon seasons. Therefore, the present study revealed that the emergence time of P. giganteus was significantly influenced by the sunset, day length, and temperature.