Why do raptors take domestic prey? The case of Bonelli's eagles and pigeons

摘要: Summary 1 Predator conservation management requires detailed understanding of the ecological circumstances associated with predation, especially that on economically valuable prey. We examined mechanisms behind Bonelli's eagle Hieraaetus fasciatus predation prey domestic origin, using dietary data from 22 pairs breeding in south-west Portugal (1992–2001) together information landscape composition and availability. 2 Numerically, 42·7% (37·7% biomass) comprised species, about 70% which were rural pigeons Columba livia remainder racing fowl Gallus gallus. Rabbits Oryctolagus cuniculus, red-legged partridges Alectoris rufa jays Garrulus glandarius most frequent wild (43·1%; 50·8% biomass). This pattern was remarkably stable over a decade, but within each year intake almost halved course season. 3 Landscape significantly affected proportion items. particularly evident territories dominated by eucalyptus Eucalyptus globulus plantations, where there reduced consumption partridges, an increased minor avian items greater diversity diet overall. 4 Bonelli's eagles showed type II functional responses while preying important (rabbit) (rural pigeon) prey, although former much stronger. Eagle rabbits declined increasing abundance pigeons, vice versa, no switching traditional sense, as selection between these two species inversely frequency dependent. 5 Synthesis applications. Predation results combination high vulnerability to shortage key such during early season. Given relatively low economic value their importance eagles, they could probably be used tool enhance food resources deflect more pigeons.