Summer food of the Pygmy Owl Glaucidium passerinum in Bialowieza National Park, Poland

Abstract

Analysis of 52 pellets of the Pygmy owl Glaucidium passerinum (L.) collected during the summer in the primeval forests of Białowieża National Park (BNP) in eastern Poland revealed 118 prey items and showed that the diet of owls was composed of birds (69% of prey number, 73% of prey biomass) and small rodents (31 % of prey number, 27% of biomass). Of the two most numerous rodents, the bank vole Clethrionomys glareolus was captured more and the yellow-necked mouse Apodemusflavicollis less than would have been expected from their availability as measured by trapping . The most numerous avian prey of the Pygmyowl were the Great Tit Parus major, the Robin Erithacus rubecula, the Chaffinch Fringilla coelebs, and Carduelis spp. A comparison with the community of breeding birds revealed that finches Carduelis spp. and tits were selected by owls. A literature review on the Pygmy owl's preying preferences on passerines showed that this predator had clear seasonal, but little geographic variation in its preferences for bird prey within Europe.