A possible case of double brooding of pharaoh eagle owls (Bubo ascalaphus Savigny, 1809) in Egypt

摘要

Multiple-brooding (raising more than one brood in quick succession, usually in less than one calendar year) occurs infrequently in owls and is generally restricted to either smaller species with shorter nesting periods or species capable of capitalizing on conditions of prolonged food abundance whenever they occur (Mikkola, 1983). Eagle owls (Bubo spp.) are the largest nocturnal predators, normally nesting only once a year (Cramp, 1985; but see Martínez et al., 2003; Ortego, 2004). In the desert breeding species, it is suspected that it breeds only once a year, with egg-laying starting in early spring and nestlings being recorded between February and June (Goodman, Meininger & Mullié, 1986; Goodman, 1990; Horner, 1992; Moldován & Sándor, 2009). This note presents the possible first recorded case of multiple-brooding in this desert species in North-East Africa, based on the observation of successive nestlings in the same territory in one nesting season.