PRESENCE OF BONE REMAINS IN THE OSSUARIES OF BEARDED VULTURES (GYPAETUS BARBATUS): STORAGE OR NUTRITIVE REJECTION?

Abstract

Abstract Ossuaries, or bone-breaking sites, are used by Bearded Vultures (Gypaetus barbatus) to prepare and store bone remains. The different nutritive values of different parts of the skeleton and bones and the fact that many remains stay in the ossuary for long periods without being consumed suggest that they may have another use besides storage. I tested whether the presence of bone remains in ossuaries may result from selection (nutrient concentration hypothesis) and rejection of bone remains on the basis of nutritive value. Of the remains found at the study sites, 84.9% belonged to medium-sized ungulates, 11.6% to large mammals, 2.5% to carnivores, and 1% to Suidae. Bone remains found were principally scapulas (14.9%), vertebrae (13.2%), skulls (12.5%), tibias (10.7%), mandibles (9.3%), ribs (8.3%), and humeri (7.2%). The larger proportion of less-nutritious skeletal parts (i.e., containing less oleic acid) and the significantly smaller proportion of distal epiphyses, which are more nutritious, sup...