Some of you may have read in the national press about the “plight of the Barn Owl”. The articles stated that 2006 had been a devastating year for Barn Owl breeding on a national scale and that the total number of breeding pairs was in the region of 3,000. At the time we tried to remain optimistic, choosing to hope that the figures were not accurate as it was still too early for all the Barn Owl conservationists to have submitted their findings for the season.
One of the reasons for poor breeding was a crash in the field vole population, the main prey species of the Barn Owl.
While this goes in 3-4 year cycles, this year has been particularly bad. A cold winter with some areas experiencing
heavy snow in March, followed by a quick thaw and then further cold weather, will have undoubtedly had some effect on
vole population at a time when field voles would ordinarily start to breed. Further cold and wet weather, with some
parts of the country seeing double the amount of rainfall in May, will have had a detrimental effect.
Of course many of you will be aware that this persistent rain and cold weather will have also affected the Barn Owl’s ability to hunt as their feathers, which allow them to fly silently, can easily become waterlogged. A combination of these factors means that some Barn Owls were too weak to have young this season or due to adult mortality may not have had a mate for the season. The few that were able to breed may have struggled to find food for their young or in some cases the female may have moved from the nest if there was insufficient prey being delivered. The result being incomplete fertilisation and chilling of eggs or starvation of the young (Shawyer, 1998)
Copyright © Mal & Jan Moore
Unfortunately, whilst optimism is a positive trait, it began to look like our worst fears were being confirmed. A preliminary report from the Barn Owl conservation network stated that figures were down in the South West, Shropshire, Wirral and mid Cheshire. In Edinburgh there have been a number of reported road kills which, although detrimental to the owl population, indicate that there are numbers of Barn Owls present.
More positively in South Nottinghamshire, it has been a record year for successful breeding and numbers appear to have remained stable. In the past, Barn Owl numbers have fallen but the population has recovered and we will only be able to determine the population trend by monitoring over the next year.
So what’s been happening in South West Cumbria?
As I started to look at the data collected this breeding season, I realised that things did not look good. Of the 67 nest sites that have been consistently monitored over the last four years, breeding pair numbers were down by approximately 50% from the 2005 and 2006 breeding seasons, although figures were slightly higher than in 2003. It looks likely that this has been due to a vole population crash that has started to recover but too late for our breeding Barn Owls to raise young .It is unlikely that any will breed this late in the year, although in theory they can breed at any time. The Cumbrian Barn Owl was in fact late to start breeding this year, with the first clutches of eggs in late May and June. Our wildlife hospital has seen 3 Barn Owl admissions during Autumn 2005 and spring 2006.
So what happens next? We hope to work closely with local people to assist with monitoring the population and to find out exactly when mating starts on the many sites we monitor. We look closely at the habitats in which the Barn Owl lives and hunts. I have already erected two brand new Barn Owl nest boxes and hope to continue this over the winter months.
We continue to remain positive about the long-term future of the Barn Owl in the UK and will continue to campaign for its protection and work closely with our partners and landowners to achieve this.
|World Owl Trust
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