While Joyce the wildlife rebilitator at Whispering Willow Wild Care takes many different kinds of animals, she has a lot of owls. Right now there are barred owls, great horned owls, and screech owls. Globally there are over 200 species of owls but here in New York State we have eight species. Owls can be found everywhere except Antarctica and a few remote islands, so chances are you have some near you too.
The smallest owl is the burrowing owl, Athene cunicularia, which grows up to 28 cm (11 in) in length, with a wing span of 61 cm (24 in). Found across North and South America, this little bird is quite interesting for an owl. As its name may suggest, instead of in trees, burrowing owls nest in ground burrows. They also come out during the day, whereas many owls prefer the night.
The largest owl is the great grey owl, Strix nebulosa, which can reach 84 cm (33 in) in length and can have a 152 cm (60 in) wingspan. These owls live in the northern part of the northern hemisphere, across Canada, Alaska, and part of the northern Untied States, as well as the northern part of Eurasia. More fluffy feathers than solid weight, they might surprise you with their power. Not only can these owls detect prey under thick layers of snow, they can crash through a layer that is hard enough to support a 81.8 kg (180 lb) person.
Owls are largely meat-eating birds that eat insects and rodents, although a few have adapted to fishing. Elf owls, Micrathene whitneyi, are one of the only species that includes plants into its diet, dining on fruits and seeds along with its nightly rodent catch.
While hooting is the owl stereotype, not all owls hoot, and even if they do, it’s not the only vocalization they can do. Actually, the great horned and screech owls seem to like hissing at people, or at least the ones I’ve been helping do. Maybe it’s just me? The barred owls have also been making an interesting clinking sound with their beaks that seem to have a similar meaning to the hissing. “Don’t touch the feathers!”
Owls cannot actually rotate their heads a full 360 degrees, but are able to turn them 270 degrees, which is still very impressive. This is the result of 14 vertebrae in their necks, whereas most birds have a mere seven. Even more interesting, at least to me, is that such a drastic turn actually cuts off the flow of blood to the head of the bird, but evolution has allowed them to develop a blood-pooling system that gives their brain blood when they turn their head so drastically. The reason for this unique head-turning ability actually is in the eyes. Owls do not have spherical eyes and are therefore not technically eye “balls”; they are more cylinder in shape which aids them in hunting prey, offering a binocular-like view. Due to this, owls cannot move their eyes like we humans can, and must turn their heads to look around.
Owls are beautiful and evolutionarily interesting birds. Next time I’ll talk about the three species I’m working with. What owl species are in your neighborhoods?