Heligan Barn Owls - May 2008
Welcome back! It's that time of year again and Hannibal the barn owl is keen to get back in the limelight. Those of you who need a quick update - here is the summary to date.
May 9th 07 - Hannibal hatched, 1 of 7 eggs
May 28th 07- Hannibal eats his first sibling
June 2nd 07- Male parent owl dies
June 3rd 07 - Only 3 chicks remain in brood
August 07 - 3 chicks fledge
August 07 - Hannibal breaks leg
August 07- Barn Owl Trust take him for vet care and rehabilitation
Sep-Oct 07 - Hannibal
cared for by BOT
Nov
07 - Hannibal returns to Heligan
Dec - Feb 08 - Weaned off extra feed
April 08 - Female arrives at nest box
May 08 - Copulation and mutual preening
May 25th 08 - First egg laid
Recognition and Habitat
The barn owl is a large bird (33-35 cm tall) with long broad wings that allow excellent manoeuvrability at slow speeds just above the ground. It is almost totally white from beneath, head and back golden buff or a rich ochre in colour with an intricate pattern of flecks and markings.
Male birds are generally paler in colour than females. Both sexes have a heart shaped face with dark eyes. Their call is a chilling screech; a long drawn out sound increasing in volume and then finishing abruptly. Other calls include chirrups, squeaks, snores, hisses and clicks.
Predators and Prey
Natural predation of barn owls is rare. Most death occurs in the winter months due to starvation of first year birds. Other causes of mortality include road death and drowning.
Barn owls are crepuscular meaning that they are active before dawn and at twilight. This corresponds with the times of greatest activity of voles, shrews and mice. Their flight is purposeful; barn owls are creatures of habit, preferring to hunt a well-known territory where their success rate is guaranteed. They will repeatedly fly back and forth over an area, a technique known as ‘quartering’. They glide a few feet above the ground, sometimes stalling, twisting and cartwheeling until they locate a target. They will then hover before plunging for the prey.
In addition to aerial hunting they also adopt a ‘perch and wait’ technique where the owl will use a post, tree stump or fence to wait for prey to pass underneath. This method is often seen during the winter time as it is more energy efficient than aerial hunting.
Life cycle
The breeding season begins in February when existing pairs re-affirm their bonds and new birds find a mate. Courtship involves aerial displays by the male and the selection of a nest site, which may be an artificial box, tree or open building. Eventually he will start to bring food to the nest site and deposit a store that is thought to trigger copulation.
The increase in prey stored at the nest site also triggers egg laying by which point the female is fed almost entirely by the male. On average 5 eggs are laid at 2 to 3 day intervals that hatch after 30 to 31 days of incubation performed only by the female. Chicks will fledge after 9 weeks and stay with the parents for tuition for a further few weeks.
Legal and conservation status
The barn owl is on Schedule 1 of the Wildlife and Countryside Act, 1981 and The Wildlife (Northern Ireland) Order, 1985. Offences against barn owls can result in a fine of up to £5,000 or a custodial sentence. It is also illegal to release barn owls into the wild in Britain without a licence. All work done at or near the nest site at Heligan is performed under licence from Natural England.
Did you know?
Tyto alba is the only barn owl species in the UK although 36 other species exist worldwide. Tyto is a Greek word meaning ‘a night owl’ and the species name alba is a Latin word meaning white. ‘Old hushwing’ is a traditional name for the barn owl.
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