© 2008 Wild Owl Web site design & photography © Ian McGuire
Vital Statistics
• Length: 33 - 35cm
• Weight: 240 - 350gms
• Wingspan: 85 - 93cm
• Breeding population:
2000 prs *
* Approximate figures based on heavy declines in 2006
• Length: 33 -
• Breeding population:
2000 prs *
* Approximate figures based on heavy declines in 2006
Over many centuries the Barn Owl was the countryman's constant companion. It was also the guardian of virtually every village church, and no barn was complete without one. Now, it is sad to say, that the British population has plummeted to such an extent present day children know the bird only from posters and greeting cards. The barn owl has been known by a variety of names over the centuries such as white owl, white hootlet, yellow owl, dylluan wen, screech owl, scritch owl, hissing owl, screaming owl, common owl, roarer, berthuan, Billy wise, Billy wix, Billy whit, cherubim, gill howter, gillihowlett, gil-hooter, gilly owlet, hoolet, hullart, hobby owl, Jenny howlet, Jenny owl, Madge howlett, Madge owl, moggy, padge, pudge, pudge owl, oolert, owlerd, ullet, ullat and woolert. Known as “cailleach oidhche gheal” in Gaelic.
The appeal of owls lies in their humanoid expressions, as they have large foreheads and their eyes are set at the front of their broad, flat faces. These type of features are in actuality adaptations for their hunting, which is mainly nocturnal. The position of their eyes confers a wide field of binocular vision, which is very important in their judgement of distance. Their size is a result of specialisation in the enhancement of their night vision. They have sensitive hearing, which is also important, and owls have relatively large ears. The openings for their ears are situated just behind the facial disc of feathers which
Identification
The Barn Owl is a medium-sized, pale owl which lacks feather ears. It has a heart-shaped facial disc, and dark eyes. The upper-parts are grey (gray), mixed with golden brown spots. In flight its very long wings are obvious, its wing span is about 90cm. It is usually a nocturnal hunter, though it may hunt by day in the winter.
Voice
Because it has such a wide range of calls, some seventeen sound signals, this has given rise to some of its folk names such as “hissing owl” and “screech owl”. There a some of these sounds are non-vocal, such as tongue-clicking, which was previously thought to be the bird snapping its beak. The screech is a penetrating, tremulous hissing scream of two seconds duration. Other sounds include a non-tremulous wailing which has been likened to that of fighting cats; a defensive hiss; "snoring" a sustained wheezy rasping or hissing; as well as a mixture twitters, squeaks, chirrups and purring (the female’s being of a higher pitch).
Hearing
The right ear opening is usually larger and higher than the left. This unusual arrangement allows owls to pinpoint their prey with great accuracy by sound alone. The Barn owls ears also differ in sensitivity to high and low frequency sounds.
Food
The Short-tailed Vole (or Field Vole), is the Barn Owl's commonest prey. They often account for more than half of its food intake during the breeding season. Also preyed on are the Wood Mouse (or Long-tailed Field Mouse), the Bank Vole and the Common Shrew.
Breeding
The pair-bonding is mostly monogamous, though the males are occasionally bigamous, and long-term. Under normal conditions courtship begins in late February. The male, during this period, hunts more by daylight in order to present food to his mate.
The pair-
As he patrols his territory he screeches so as to repel any rivals and also to attract the female. There is a good deal of attachment to traditional nest sites, and successive pairs tend to use the same ones for twenty or even thirty years. There are well authenticated cases where sites have been used in excess of a hundred years. The widespread use of artificial nest-boxes has over the recent past, proved to be successful. No nest is made, and even a scrape is thought to be no more than the fortuitous creation of the male's courtship behaviour. But, because the breeding season is so long, by the time the eggs are laid, there is often a soft bed of pellets and feathers. Between 4 and 6 un-glossed eggs are laid in April or early May. The eggs are incubated, almost entirely by the female, once the first egg is laid. The male feeds the female during the incubation period. The eggs hatch (asynchronously as with laying) after 32 to 34 days, and the young enjoy a remarkably lengthy fledging period of usually 60 days but can be anything up to 86 days. There are frequently 2 broods per year.
Nest Sites
In the British Isles usually select from one of three types of nest site: the insides of buildings, large tree cavities and rock cavities. The owl’s plumage has very little oil and is therefore easily waterlogged, so in areas that are predominately wet - such as Devon - 95% of nest sites are in buildings and in dryer areas - such as Suffolk - 70% nest in trees.
Conservation
Barn Owls are now so rare that they have special protection under Schedule 1 of the Wildlife and Countryside Act (1981) - under which it is an offence to intentionally disturb these birds while they are preparing to nest or during the
actual process of breeding. Their decline is due in part to the persistent use of organo-chlorine insecticides, pesticides and rodenticides along with barn conversions, innumerable nest-sites in trees and buildings have been lost, trees in particular due to Dutch elm disease and freak storms. But a far greater impact on this decline has been the demise of their natural breeding and hunting ground - long grassed meadows. As the meadows disappear so does the mainstay of the Barn Owl’s diet, the Short-tailed Field Vole. Now, thankfully, the Barn Owl has gathered some friends in the conservation movement. There projects in place, such as captive-breeding and release programmes, which are designed to improve its status.
Information from the World Owl Trust www.owls.org
