THE EAGLE OWL
In the department of the Aude we have a hill range, La Clape, which has the highest density of Eagle Owls (Fr. le Grand-duc), in France; the largest owl in the world. Found over a very large proportion of the world, this is a super-predator with a wide diet so capable of adapting to many different habitats, and recent recovery in numbers has led to them turning up in unlikely places, cities even. It is visually remarkable with the ear tufts and orange eyes.
Like some other owl species, perhaps because of their nocturnal habits, they have relatively little fear of man, and are not too difficult to see, and above all, to hear. They are simply enormous, the wing span of a golden eagle (170 cms.) and although a little shorter in length the massive bulk of the body is unmistakable as it flies against the fading light of evening sky, which is how I often see it; I am lucky to have a resident pair nesting within 3 kilometres of the mill, and they are there throughout the year.
However it is by its call that you can most easily find this bird. The Dutch name for this owl is oehoe, an accurate verbal rendering of its’ two note song, oo-hu, sometimes audible at several kilometres away, a sound capable of sending shivers through your spine, unmistakable.
Hard to find during the day, they roost in amongst the branches and leaves of tree, their camouflage blending perfectly with the dappled colours of the background, but as dusk falls in winter evenings the deep notes of the male echo around the cliffs, sometimes answered by the female with a higher pitch. The white throat patch inflates as he calls from his rock, and is clearly visible. This is often followed by a low flight above the crest, to perch again on another outlook, looking around before finally starting off on a night’s hunting.
The two ear tufts (Fr. aigrettes) – are not really ears at all, but another visual signal with which the mood of the bird is transmitted - anxiety, aggression, relaxation – and can be raised and lowered at will. The tufts can give the impression of a crown, and in Italian and Spanish they are known as royal owls.
The actual ear openings of owls are hidden under the facial plumage, and are asymmetrically placed so that perfect pinpointing of the slight sounds of the prey can be made, somewhat like our two eyes interact to give a sense of distance. A higher ear opening on one side increases the accuracy of locating the prey's position.
The flight of an owl is
absolutely silent. Recent studies on similar species - the Great Gray Owl - that hunt exclusively by sound - has revealed that a line of very soft fringes
along the edges of the wing feathers mute the sound of the beats so a stealthy
approach can be made with no audible alarm given to the prey - and enable the owl to hear better, with no noise interference. To minimize any bending of the acoustic mirage caused by the snow above which the Great Gray hunts, the owl will hover vertically above the sound for a few moments, before plunging down. It is probable that other owls have similar adaptions, amongst them Eagle Owls that hunts by both sound and sight.
The power in the legs and talons is remarkable; once helping a vet to take an x-ray of an injured eagle owl I was asked to hold the two legs as it lay on its back, and the force against my hands was tremendous. Finishing in large, powerful talons, you can tell that once gripped there would be little chance of survival for the prey.
Like other large birds they start nesting early in the year; the males will call to reinforce the territorial dominance in November, before quietening down after the eggs have been laid and the female is sitting. The male comes in with prey – nearly anything they can carry – and will leave it at some distance from the nest cavity for the female to fly across and collect. Like many raptors the females can be one third larger than the males, and by keeping his distance he is showing her a healthy respect.
The reason why Eagle Owls numbers have substantially increased in the last few decades is that a successful pair is capable of raising several chicks in one clutch, if the male works hard enough to bring in the food. The nest is very simple, merely a scrape in the floor of a suitable rock overhang, as seen below
These are birds that are sometimes raised in captivity and trained to fly to the fist. I once went to a talk in a village hall where the falconer had an Eagle Owl on his fist. Someone came in with a small lapdog under their arm. Within seconds the mesmerizing orange eyes had fixed on its potential supper, the poor beast realised that it was on the menu and started to whimper, and had to be hastily removed.
The history of the Eagle Owl in the U.K. is a complex one. The Scots Gaelic, Manx, Welsh, Cornish and Irish Gaelic languages all have words for them and it is generally agreed that fossil records indicate eagle owls were present in Britain from some 700,000 years (to at least 10,000 years ago), but the evidence for more recent presence is inconclusive.
About 30 years ago a pair was found to be breeding on a military site in Yorkshire. There are claims that 23 chicks have been raised to fledging since, and there are now possibly 40 pairs nesting throughout the U.K..
However this is not been universally welcomed by all interested parties. The doubt revolves around the origin of the birds. Have they flown across the channel from Europe – they are sometimes seen resting on oil rigs in the North Sea - or are they escapees from captivity? Being an apex predator, and also hostile to many other raptors within their nest territory, up to the size of (and including) goshawks and buzzards, there is some evidence that other protected species are adversely effected by their presence.
Nevertheless this is a magnificent bird, and the RSPB at least has indicated that they would not support any attempt to cull the species. Here, in France, it is accepted as natural part of the avifauna pyramid, and the recent revival in numbers after the persecution of the 20th century has been welcomed. Estimates vary between 1100 to 3000 pairs.
I can remember well the thrill I had when I first heard and saw this impressive species.
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