There are over 200 different species of owl, spread all over the world. The largest species of owl is the European Eagle Owl from north and west Europe, while the smallest is the Elf Owl from South America/Mexico. They have a number of amazing adaptations to help them hunt and survive in the wild.
There are six species of owl that are native to the United Kingdom. The most common is the Tawny Owl, which is the only owl that makes the ‘twit-twoo’ noise we all think of as a typical owl noise. Then there is the Little Owl, the Barn Owl, the Short-Eared Owl, the Long-Eared Owl, and the Snowy Owl, which is sometimes seen in Scotland when it migrates for the winter.
Most owls typically come out at night. Animals that are active at night are known as nocturnal. Because most owls come out in the dark, they have adapted to use their hearing to find their prey, instead of their eyesight. Some owls, like the Long-Eared Owl in this photograph, have ‘ear tufts’ on top of their heads. These are not actually their ears and have nothing to do with hearing! These tufts of feathers are thought to help with camouflage as they help to break up the owl’s profile and let them blend in with their habitat. You cannot actually see an owl’s ears because they are holes on either side of the owl’s head, just behind their eyes, and hidden by their feathers. An owl’s ears are also in slightly different places – one is in line with the eye on one side of the head, and the other is just underneath the eye on the other side. This means that sounds reach each ear at very slightly different times, and this tiny time difference allows an owl to pinpoint exactly where a sound is coming from.
An owl also has a facial disc which they use a lot like a satellite dish, to pick up sounds and hear them more clearly. This facial disc acts in the same way as the fleshy bit of our outer ear, but is much more sensitive. The bigger an owl’s facial disc is, the more sensitive its hearing is. The owl with the largest facial disc in the world is the Great Grey Owl, which has hearing so good that it can hear a lemming running around underneath 30cm of snow!
Although owls mostly use their hearing to hunt, they do have amazing eyesight. Owls cannot see in complete darkness, but they need a lot less light than we do to be able to see. A Barn Owl can see perfectly well just by the light of the moon and the stars!
Not all owls come out at night, although most do. You can usually tell what time of day an owl hunts my looking at the colour of its eyes. For example:
- An owl with very dark coloured irises (the coloured part of the eye), is normally nocturnal.
- An owl with yellow coloured irises is generally active during the day, which is called being diurnal.
- An owl with orange irises is usually crepuscular, which means they are active at dusk or dawn.
An owl’s eyes are absolutely massive, much bigger than ours. Their eyes take up around 80% of the owl’s skull – if we had eyes that big it would be like having two small oranges for eyes! They are also a different shape to ours – our eyes are round, like a ball, so that we can roll them around in their sockets. Try moving your eyes up and down, side to side, without moving your head. An owl cannot do this! An owl’s eyes are shaped like tubes, and go back into their skull a long way, so they cannot move their eyes at all. This is why they can move their heads so much – an owl can turn its neck up to 270 degrees in either direction. This means there is something we can do that an owl cannot – we can go cross-eyed, so that we can focus our eyes on things that are close to our face. Try it and see: hold your arm out in front of you with one finger pointing up. Focus your eyes on your finger and then slowly move your finger towards your face while keeping focussed on your finger. Your eyes will automatically move in towards your nose, making you cross-eyes and allowing you to stay focussed on your finger!
Because owls cannot move their eyes, it means that they cannot see things that are very close to their face. It is a little bit like looking at the world through a pair of binoculars; everything in the distance is very clear and very focussed, but anything close up will be blurry as the owl cannot refocus its eyes to see near to it. Instead, they use the long, thin, sensitive feathers around their beaks to feel around for thing that are close to them, a lot like a cat using its whiskers. They will especially do this when they have caught their prey in their feet so that they can eat it!
Owls fly silently, unlike most other birds. If you have ever heard a pigeon take off, for example, you might have heard lots of loud flapping noises. This is not their wings banging together such as we might clap our hands to make a noise; it is just the sound of air moving around and over the bird’s wing. Owl wings are very big and their feathers are very soft; this means that they do not disturb much air when they fly, so they are silent. This helps them to sneak up on their prey, and it means that there is no noise from their flying that would stop them from hearing the sounds their prey is making – remember that an owl finds its prey using its hearing, so this is very important!
Feet & Claws
Owls have very strong feet and sharp claws that they use to catch hold of their prey. Once an owl has got hold of its prey, they will grip very tightly to stop their prey from escaping. Having strong feet also helps them to hold on to perches when they are not flying.
Beak, Feeding & Owl Pellets
Owls have a hooked beak, similar to birds of prey, but they do not usually tear up their food unless they are feeding it to their babies. Instead, an owl will usually swallow its prey whole if it can. Once they have digested their meal, they will regurgitate a pellet. This pellet is made up of all the bones, fur, feathers and other bits of their prey that they cannot digest. Some people will collect owl pellets and take them apart to see what the owls have been eating. You can search online to find owl pellet dissection kits if this is something you would like to try!