Some African vultures overcome the calcium deficiency in their diets by ingesting bone fragments, and are dependent on the presence of large predators to supply them (Mundy and Ledger 1976, S. Afr.J . Sci.7 2:106-110; Mundy 1982. The comparative biology of southern African vultures, Vulture Study Group, Johannesburg, South Africa; Richardson et al. 1986, J. Zool. Lond. 210:23-43). Because of the lack of large mammalian carnivores in the Iberian Peninsula, vultures apparently satisfy their calcium needs by ingestings mall bone fragments from carcasses(Köng 1975, Ardeola 21:219-224) or small pieces of limestone (Fernández 1975, Ardeola 22:29-54; Elosegi 1989, Acta Biol. Mont. 3, série documents de Travail). This note reports several observations of Griffon Vultures (Gyps fulvus) making use of bone splinters obtained from Bearded Vulture (Gypaetus barbatus) ossuaries where large bones are deliberately dropped on to rock slabs (Boudoint 1976, Alauda 44:1-21).

This study was supported by the Departament d 'Agricultura, Ramaderia i Pesca de la Generalitat de Catalunya.

Peer reviewed

Letter.