Food and Hunting
All owls are predators and the size of the prey is generally reflected by the size of the owl. The Elf and Pygmy Owls prey on a variety of insects, spiders and other invertebrates, although, some are quite voracious and can take birds as large as themselves. Eagle Owls, at the other extreme have been known to take such formidable prey as Golden Eagles and a Roe Deer of 13kg as well as foxes, herons, domestic dogs and there is apparently a report of a large Siberian Eagle Owl taking a ¾ grown wolf!
Hunting, normally, is performed in two different ways. The first is perch hunting, where the bird literally sits and waits on a suitable perch until a prey item is located. The other technique is flight hunting where the owl slowly quarters the ground from a low altitude, looking and listening for prey and diving down when food is detected. The length of the wings is normally a good indication of the preferred method of hunting - short wings for perch hunting and long wings for flight hunting.
Most owls are opportunists and virtually anything that moves is fair game. Some species are more specialised feeders, in particular the Fish and Fishing Owls. These are two genera of owls, one from Asia and the other from Africa whose members feed mainly on fish, amphibians and aquatic invertebrates, snatched from beneath the water surface.
No other species are quite so specialised but some have a preference for particular prey. The Milky Eagle Owl of Africa feeds on a wide variety of prey, but where the ranges overlap it seems particularly partial to hedgehogs. The Eurasian Eagle Owl would appear to have a vendetta against other birds of prey, especially other owls. In some areas they form 10% of the bird’s diet, which is much greater than one would expect from chance. We must point out the majority of their food is Rabbit.
A Short Tailed Vole, the essential prey item of the Barn Owl.
Owls Will often sit and "Still hunt" looking and listening for prey from a good vantage point.
A Barn Owl floating across a field "Quatering" looking and listening for Short Tailed Voles.