UK Wildlife

Barn Owl Population and Winter Mortality

The barn owl is one of the UK's most beloved birds but faces severe population fluctuations, with cold, wet winters causing mass mortality when vole prey becomes inaccessible under snow or flooded fields.

Key Facts

UK barn owl population fluctuates between 4,000 and 10,000 pairs depending on winter conditions
Cold wet winters cause death of 70% of young birds and significant adult mortality
Barn owls have evolved the most sensitive directional hearing of any tested animal
Hunt by sound in complete darkness, targeting vole movements under vegetation
Nest box provision has significantly helped stable populations through supplementary sites

Welfare Considerations

Barn owl winter mortality from starvation is a major welfare concern. Cold, wet winters when snow covers prey are lethal for birds without fat reserves. Nest box provision benefits populations, but maintaining rough grassland vole habitat is equally essential.

What You Can Do

Install barn owl nest boxes on farm buildings following Barn Owl Trust guidance
Maintain rough grassland habitat on farmland to support vole populations
Donate to Barn Owl Trust conservation and monitoring programmes