Listening to owls marking their territory

LAST week I was in England, visiting friends in a rural part of Devon.

One night around midnight I went outside for a smoke. It was a still, frosty winter night and it was filled with strange and beautiful sounds.

I thought I knew what was going on but I called an Englishman out of the house to confirm it for me. He agreed that what we were listening to was tawny owls marking their territory. There are no tawny owls in Ireland which is why I needed the confirmation.

Describing bird calls in words is not easy but I’ve found quite a good description of this extraordinary sound in ‘Birds of Europe’ by Lars Jonsson. “Male’s territorial call consists of two mellow, whistled hoots, slightly desolate but woodwind in tone: “pooOOH” after one to four seconds followed by “poo, poo-ho-ho, HOOO-OOOOO”, the latter part drawn out and tremulous — sometimes the first or second half is omitted.”

On that night in Devon at least four owls were performing this concert.

One was very close, the others were distant and coming from different points of the compass. It sounded as though each male owl had a territory of a couple of square kilometres and was proclaiming this fact to the others and, presumably, trying to attract a female owl.

Later on in the trip I saw an owl in the headlights of the car. But this was a barn owl, a much more familiar bird as they’re found in Ireland and there’s a pair living quite close to my home. The ghostly white silhouette floating silently through the trees was unmistakable.

Apparently tawny owls are common in Britain but barn owls are rare and declining.

Barn owls are one of the most widely distributed birds in the world, occurring in temperate and tropical countries. But they’re rare and declining in Ireland as well and, as far as I know, in most other countries. They eat small animals like rats and mice. An increase in the use of rat poison and the shortage of suitable nesting sites may be reasons for their decline.

In Ireland, despite being rare they’re quite widely distributed but with a greater concentration in southern and eastern counties. The total population in the 32 counties is probably only 150 to 200 breeding pairs, which means they are of conservation concern.

Our commonest owl is the long-eared. Census figures are a bit vague for this species at present but there are probably more than 1,100 and less than 3,600 breeding pairs in the country and this number is augmented by an unknown number of winter migrants from more northerly countries.

Long-eared owls also call to proclaim their territories at this time of year. If you think they may breed in your area it’s worth going out to listen for them. It’s not as spectacular a sound as the tawny owl but it’s quite distinctive — a repeated and long drawn out “oo-oo-oo”. Apart from the odd vagrant, the only other Irish owl is the short-eared — a bulky, blunt-winged bird which is less nocturnal than the other species. They occasionally breed in Ireland but are normally just winter visitors from the sub-arctic.

I occasionally see short-eared owls on raised bogs where I live in the midlands. I think the heathers, grasses and mosses of the bog remind them of the tundra they have come from. They mostly hunt small mammals and there are few if any small mammals in Irish raised bogs so either they fly out into the surrounding farmland to feed.

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