Breeding Behavior of Black Vulture In Erdenesant, Mongolia

몽골 Erdenesant 지역의 독수리 번식행동

We studied the behavior of black vultures breeding in Erdenesant, Mongolia through time budget observation. We observed a pair of black vulture for 115 days from April 30 to August 22, 2005, of which 15 days were before hatching and 100 days of brood rearing. The egg hatched on May $14^{th}$. Incubation was done by both a male and female vultures, but the period covered by the male vulture(56.82%) was longer than that by the female one(34.62%). In the early days of brood rearing, time spent by the female vulture at the nest took 54.9 % and it was 19.27% for the male. In the middle of brood rearing period, just inaction and preening were noticed, as they watched their chicks for a long time without sheltering chick under the parent's body. Late brood rearing period was characterized by less chick care and adults mostly stayed in the nest only when to feed the chicks. During breeding time, both the male and the female vulture fed only the chicks and did not give food to each other. During rearing period, the male vulture fed the chick more often than female.