Tawny owl by Graham Osborne
The sun is low over the western horizon and the sky painted with the glorious pink and orange hues of sunset. Dark silhouettes fly overheard calling ‘jack, jack’; the jackdaws and rooks are heading to bed. As the light fades further you can hear the noisy blackbirds – not the mellow song of the morning but the harsher ‘chink, chink’ calls that signal dusk. And then it becomes twilight and the tawny owl begins to call.
Owls are creatures of the night, a rare trait in birds with less than 3% being nocturnal, and they are perfectly adapted for it. The beautiful plumage allows the owl to blend into its chosen habitat with ease, allowing it to roost in peace during the day. For tawny owls, the mottled browns and soft creams disguise the bird alongside the bark of a tree.
Owls are also renowned for their eyesight. The iris of an owl’s eye can open almost completely to allow in all the light that is available, and maximise their ability to see in the dark. But owls don’t just rely on superb eyesight to find their prey, they also hunt by sound and in fact their ears are even more remarkable than their eyes. The ears of an owl are positioned asymmetrically which means that each ear hears sound at a slightly different time, volume and angle, allowing the owl to pinpoint where the sound came from. And they are capable of detecting time differences of as little as a 30 millionth of a second – they can hunt and kill by hearing alone.
They are stealth predators, boasting special feathers that facilitate silent flight – with comb like serrations on the leading edge of the wings and a velvety fringe on the trailing edge which dampens any noise. And the feathers have an overall softness that creates little or no noise as the wind passes through them. Having located their prey and approached it in silence, the owl will strike with its feet pushed out in front and talons open. A swift nip from the owl’s hooked bill will, if necessary, finish the job.
The tawny owl is probably the most common owl on the reserve. I’ll admit that they are a challenge to see, but you can certainly hear them. They will have begun to stake out their territories. Male and female tawny owls do so by performing a duet which is one of the best known of all British wildlife sounds. The male gives a long quivering hoot which is followed by the females sharper response. This duet tells any other owls that are around that the territory is well and truly occupied by a breeding pair. It might well be the youngsters of the pair who are trying to muscle their way in; tawny owls are quite sedentary, never moving too far away from their birthplace so a good territory must be defended long before breeding starts.
The tawny owl breeds relatively early and you could expect to see the lovely fluffy youngsters in April or May. Balls of grey-brown downy plumage may be spotted near to the nest hole or box as the young owls ‘branch’ – exploring the nearby trees – well before they can fly. You can be sure that the female owl will be close by, well-hidden but keeping a watchful eye on her owlets and on anyone else in the area. Seeing a young owl is a treat but she’s a proud mother so admire the owlets from a safe distance and move on before she gets cross with you!
See & hear tawny owls: Seeing tawny owls is quite a challenge but they can regularly be heard calling during our night-time events. The lovely mature oaks around the edge of the heathland trail have lots of suitable holes for nesting tawny owls.
‘Heathland heroes’ is a series of blogs celebrating some of the fascinating creatures that we find on our wooded heathland. Lowland heathland is an incredibly rare habitat and just 16% of the heathland that existed in the UK in 1800 is left, so the heathland we have here is incredibly precious.