Biology and Environment: Proceedings of the Royal Irish Academy

Abstract:

This study presents an account of the diet of barn owls Tyto alba (Scopoli) which fed mainly on two invasive species in County Cork, Ireland during a one-year period. Greater white-toothed shrew Crocidura russula (Hermann) (68%) and bank vole Myodes glareolus (Schreber) (18%) constituted 86% of diet by number and 76% by biomass. Among indigenous species, numbers of brown rats Rattus norvegicus (Berkenhout) (2.8%), field mice Apodemus sylvaticus (Linnaeus) (9.6%), house mice Mus domesticus (Linnaeus) (1.2%) and a single pygmy shrew Sorex minutus Linnaeus (0.2%) formed a combined total of only 13.8% among the total of 508 rodent and shrew prey items recovered and identified. Barn owls preyed almost exclusively on invasive species as soon as they became established in the environment, the greater white-toothed shrew being an important prey species in all seasons of the year.