Wildlife: Secrets of a muted hooter
Saturday 14 February 1998
A deep hoot in the night - like air blowing over the top of a glass bottle - signals the presence of one of Britain's rarest and most beautiful owls. Secretive and strictly nocturnal, the long-eared owl (asio otus) is at home in woods near rough grassland. Its reclusive nature and excellent camouflage make it devilishly hard to find, which has meant previous studies of this species have been difficult - and results limited.
However, recent research by Robert Williams of the University of East Anglia in Norwich has revealed important new information about this elusive bird of prey. Dr Williams has found more evidence to suggest that Britain has a self-supporting resident population but also fears that the bird is suffering a decline in numbers.
A self-supporting resident population has been suspected by scientists and ornithologists but Dr Williams's evidence is the strongest yet to prove it exists. "There have been records of long-eared owls here for years. All the places in East Anglia ending in Hoo were named after the call of the male long-eared owl," Dr Williams said. "It was not known whether all the winter migrants returned to Scandinavia in the spring or whether some stayed here to breed."
Many long-eared owls still make that perilous journey each spring from Britain to their northern breeding grounds. Their numbers vary from year to year, with peaks every three to five years. But Dr Williams discovered that those owls living in southern England, where prey is more consistent and reliable, seem to be resident year-round.
"If it is a particularly poor year for prey or an especially harsh winter, the resident birds will moderate their breeding and maybe not even breed at all," he said.
During his PhD study, Dr Williams also discovered that long-eared owls have lower juvenile and adult survival rates than tawny owls, which are doing well at the moment, and that the UK population was dwindling, with the major causes of death being predation, starvation and bad weather, as well as increasing numbers being killed on the road.
"They do seem to have declined this century. We don't know what their natural level is because they are so secretive, but the Victorian naturalists talked about them as if they were much more widespread than they are today.
"The naturalist C B Ticehurst said they were more common in parts of the south than the tawny owl," Dr Williams added. "As the tawny has increased in numbers recently, the long-eared owl has appeared to decline. We still don't know if there is a connection between the two. We also know about the decline from local county bird reports. They don't breed at all in Cornwall and there are very few pairs in the south west of England. It is estimated there are between 1,000 and 10,000 pairs in the UK now. My guess would be around 2,000 pairs."
The chief reason behind the decline is the problem affecting many bird species - agricultural and land-use changes which have meant the destruction of the blackthorn scrub and fenland of the long-eared owl's natural habitat. The owl is a vole specialist and relies on this rough grassland for hunting.
Dr Williams is keen to draw attention to the plight of the species and possibly get it registered as a bird of concern. During his three-year study he found 24 nests with eggs (indicating a breeding pair) and went to extraordinary lengths to get those results, spending nine months in the wilds of Kielder Forest in Northumbria, living owl hours, with only one trip home every four weeks, and braving an icy Force Six wind on the Old Hall Marshes in Essex.
"Radio tracking long-eared owls is really difficult because their range is so great," Dr Williams explained. "They are not like tawny owls, which fly from perch to perch to hunt for food, they hunt while flying over open grassland. The only way to follow them is to run after them, so I spent many nights running across wild moorland trying to keep them in range. I fell down pits and holes and into bogs. I was stopped by the police several times when farmers called in to say they'd seen this character running across the moors adjacent to their land in the middle of the night."
He also had some close encounters with his subjects. While he was ringing chicks in a nest, one female long-eared owl made fly-pasts near the nest, clipping the back of his head with her wings, trying to scare him off.
But despite the hardships, he brought home results which will go some way in helping us to understand this most elusive of birds and to ensure its survival.
To find out more about long-eared owls, contact the Hawk and Owl Trust's education centre on 01494 876262 and look out for a book, `The Long-eared Owl' by Derrick Scott (Hawk and Owl Trust, pounds 17.95).
David Haines remembered: Death of British hostage executed by Isis lamented from the Balkans to Sudan
Jennifer Lawrence and Kate Upton nude pictures exhibition cancelled after artist concedes photos were 'stolen property'
David Haines beheading: David Cameron says Britain will hunt down Isis 'monsters' shown in video murdering aid worker
Piers Morgan attempts to save the Union by promising to go back to the US if Scotland votes 'No' to independence
Jennifer Lawrence to make public appearance after nude photo hacking scandal as Met Gala Ball 2015 co-host
Daniele Watts: Django Unchained actress detained in Los Angeles after being mistaken for a prostitute
George Galloway on Scottish independence: The political class is doing what Hitler couldn’t – destroying Britain
Scottish independence: Nationalist leader Jim Sillars threatens pro-union companies with 'day of reckoning' after independence
Scottish independence: Yes campaign feels the heat as Alex Salmond's NHS claims come under furious attack
Scottish independence: Britain faces 'constitutional crisis' at next election
£23m Birmingham cycle scheme is attacked by Tory councillor for not catering to the elderly
- 1 Scotland independence vote: Everything you ever wanted to know about life after the result
- 2 Lego breaks out of the toy box and heads for the gallery
- 3 A bottle of wine a day is not bad for you and abstaining is worse than drinking, scientist claims
- 4 Piers Morgan attempts to save the Union by promising to go back to the US if Scotland votes 'No' to independence
- 5 Tyler, The Creator says having the new U2 album automatically downloaded on his iPhone was 'like waking up with herpes'
£50 - £65 per day: Randstad Education Leeds: We are looking for flexible and i...
£50 - £65 per annum: Randstad Education Leeds: We are looking for flexible and...
£130 - £160 per day: Randstad Education Leeds: Qualified KS2 Supply Teacher r...
£130 - £160 per day: Randstad Education Leeds: Qualified KS1 Teacher required,...