Post-fledging dependence period and development of flight and foraging behavior in the Egyptian Vulture Neophron percnopterus.

In northern Spain the first flights of fledgling Egyptian Vultures Neophron percnopterus took place between 28 July and 28 August (at the age of 68-80 d). The post-fledging period ended between 29 August and 5 September when the young migrated (at the age of 89-113 d). The length of the post-fledging period was between 9-34 days and correlated negatively with the date of first flight. The number of flights carried out per day, the flight duration, the time spent flying, the time spent soaring and the size of the home range increased with age. Older fledglings in broods of two were more precocious and active in flight than their siblings. Early self-feeding both on carrion not brought by parents and on food pirated from other Egyptian Vulture nests was observed. The young followed their parents during their visits to feeding places; this behaviour is unusual among raptors and may be related with maturation of social foraging strategies.

Ferrer M., Garcia L. & Cadenas R., ARDEA 78 (3): 387-394.