Abstract
It would be difficult to name a bird that is more beneficial to mankind than the Barn Owl. This analysis of its food is based on nearly 48,000 prey items collected over 12 years and shows that 900 of the diet comprises rodents and shrews. Chief among these are the shorttailed vole, but in Ireland (where this is absent) and the cereal-growing country of eastern England, this invaluable ally of the farmer is an inveterate enemy of the brown rat.