Time activity budget of White-rumped vulture and Slender-billed vulture during breeding in captivity

Abstract

Time activity budget is a widely used method to study the behavioral patterns of a range of animals including mammals and birds. The time budget of breeding birds offers valuable information regarding parental participation, incubation and chick rearing. The Gyps vultures were not intensively studied until recently. The Vulture Conservation Breeding Program of the Bombay Natural History Society is the first to hold and breed the resident Gyps vulture populations in captivity for their reintroduction in the wild. Hence, the White-rumped vulture and Slender-billed vulture were scientifically maintained in captivity and studied for their time activity budget. The aim of the study was understanding the role played by both sexes in breeding and derive the major activities of the parents and their offspring in the nest. The nesting vultures were observed with binoculars and through CCTV camera installed in the aviaries, during the day time from 06:00 to 17:30 hours to record activity of each parent at five-minute intervals. The activities for male and female individuals were divided into pre-hatching and post-hatching activities. Activities such as nest building, incubation, brooding and taking care of nestlings were recorded. Incubation and brooding were found to be the major activities of the breeding birds in both the Gyps species included in this study. Male and female individuals equally contributed for the incubation of the egg underlining their monomorphic nature.