Northern Prairie Wildlife Research Center
Surendra P. Goyal, J. B. Sale, and A. Gupta, Wildlife Institute of India, P.O. Box 18, Dehra Dun 248001 India
We discuss some of the problems encountered during tagging and tracking radio transmitters in a study on foraging and reproductive behavior of Indian Flying Fox (fruit bat, Pteropus giganteus) at Dehra Dun (30° 24' N; 78° 05' E). Four adult individuals, two each of male and female fruit bats, were radio-tagged (Telonics model MOD 075). An adult female weighing 623 g did not fly when a radio transmitter was put around the neck, and she remained on the same tree. Later on, the transmitter was put on the back of the animals using a leather belt harness, and animals could fly with their normal behavior. Since the transmitter antenna was hanging on the back, it was chewed by one of the males 15 days after tagging. Transmitter signals were audible up to a distance of 5 km. Radio tracking was done by noting bearings of the flying path from the nursery roost (NR). By the time we reached the second point for tracking on its flying path within 5 km, most of the time animals were out of the tracking range except in a few cases when animals foraged <5 km from NR. It was not possible to track animal during night in surrounding mountainous forest habitat as there were no motorable path and it was the tiger and elephant habitat. Since we did not get much success in tracking animals, we abandoned normal tracking and monitored only flight directions from NR. Thus, the objectives on foraging behavior were not achieved, and we could only conclude that animals foraged >10 km from NR. Radio-tagged animals were used to collect data on arrival and departure time and use of roosting tree at NR. We tried to answer whether suckling juveniles of Indian Flying Fox are taken to the foraging ground by their mother by radio-tagging two juveniles along with the mother. We monitored simply the presence or absence of signals of radio-tagged individuals at NR. Suckling juveniles were taken to the foraging ground by their mother and returned to the NR with the termination of activity by early morning. Suckling juveniles of about two months old foraged independently within 300 m from NR. Thereafter, we could not track juveniles as transmitter range was only up to 300 m and animals foraged mostly >300 m. The mother did not return from the foraging ground to nurse the young during the night. During the Forum, we would like to discuss the best way of radio tagging and tracking Indian Flying Fox. This would enable us to plan a successful radio telemetry study in future to understand the role of this species in maintaining forest biodiversity and to enhance its conservation.