Dietary biology of the Eurasian eagle-owl
The Eurasian eagle-owl (Bubo bubo) may well be the most powerful extant species of owl, able to attack and kill large prey far beyond the capacities of most other living owls. However, the species is even more marked for its ability to live on more diverse prey than possibly any other comparably sized raptorial bird, which, given its considerable size, is almost fully restricted to eagles. This species can adapt to surprisingly small prey where it is the only kind available and to large prey where it is abundant. Eurasian eagle-owls feed most commonly on small mammals in the 100 to 2,000 g (0.22 to 4.41 lb) weight range, although nearly 45% of the prey species recorded have an average adult body mass of less than 100 g (3.5 oz). Usually 55-80% of the food of eagle-owls is mammalian.