Britain's Barn Owl Bonanza
?large broods and the earliest ever season…It’s a busy summer for Barn Owls – and for the birdwatchers who monitor their nesting success – with large broods and the earliest ever season. Millions of people were entertained by the BBC Springwatch Barn Owls during June. The five youngsters, shown nightly to BBC2 viewers by Bill Oddie and Kate Humble from the Fishleigh Estate in Devon, were all ringed and we know that they all fledged successfully, with the last youngster leaving the nest just two weeks ago. This wonderfully successful story has been repeated across the country, thanks to a glut of small mammals upon which the birds feed.
The success of Britain’s Barn Owls is assessed by volunteers and professional biologists working for the BTO-led Barn Owl Monitoring Programme. Initial reports show that prolific sites span Sussex, the chalk valleys of Hampshire, Devon, Salisbury Plain, Northamptonshire, North Lincolnshire, Nottinghamshire, parts of the East Midlands, East Anglia, East Yorkshire, Cumbria and the Solway plain. It seems to have been a less successful season for Cambridgeshire and other parts of southwest Scotland, after a productive 2004 season in these areas. Colin Shawyer of the Wildlife Conservation Partnership said: “These are the earliest egg-laying dates we have seen in twenty years of Barn Owl recording in Britain. Most clutches were started in the first week of April, over two weeks earlier than average. Across the country, young Barn Owls are already learning how to fly and to hunt for their own food.” [The Wildlife Conservation Partnership (WCP) helps to develop and refine the research methodology for the BTO’s Barn Owl Monitoring Programme. As a key part of the Project, WCP gathers breeding data and rings many adult and nestling Barn Owls at a defined set of 200 sites throughout England.]
Scientists are linking the early and successful season for Barn Owls to the bumper crop of fruit and seeds last autumn. It is anticipated that many birds will now attempt to raise second broods, further adding to the productivity of the season.
David Glue, BTO Research Biologist explains why this is such a good year: “The four main food items taken by Barn Owls are Field Vole, Wood Mouse, Brown Rat and Common Shrew. Last winter there was an exceptional glut of wild fruits (including beech mast and haws), which was great news for these small mammals. The rodents, in turn, provide a ready food supply for Barn Owls.” - A pair of Barn Owls needs to find about 4,000 small rodents (each weighing around 20g) in order to successfully raise a brood of young.For young birds, fresh out of the nest, there are many challenges ahead. We know, from reports of ringed birds, that many will die in the first few months, often as a result of collisions with cars - sadly, lots of these owls meet untimely ends as they try to get to grips with a world dominated by man. For instance, a large proportion (45%) of ringed Barn Owls are reported as road casualties. A slightly less predictable cause of death is drowning in water troughs; this mainly seems to be a problem for breeding females, desperate to bathe after weeks sitting on their eggs.
Humphrey Crick, Senior Populations Ecologist with the BTO said: “The Barn Owl population of England and Wales dropped by two thirds in the last sixty years of the twentieth century. However, farmers, foresters and other landowners have done much, through habitat creation and by providing nesting boxes, to help these wonderful birds. Volunteers taking part in the BTO-led Barn Owl Monitoring Programme are helping to ensure that we keep a close eye on the 4,000 remaining pairs.”
4th July 2014