The Diet of rhe Tawny Owl (<i>Strix Aluco</i>) in South-Western Lithuania during the Breeding Period

Abstract

The paper presents the material on the Tawny Owl (Strix aluco) diet collected during the breeding period (April–May) in Šakiai district. Prey remains from 11 nestboxes occupied by owls in 1986–1987 and 1997–2004 were analysed. The remains of 15 small mammal species, 18 bird species, two amphibian species and two genera of insects were recovered. The dominating small mammal species (n = 361) were Clethrionomys glareolus (24.6%), Microtus arvalis (20.5%), Apodemus flavicollis (11.6%), Microtus agrestis (8.8%) and Sorex araneus (8.6%). Among birds, the most often preyed were Turdus philomelos, T. merula, Fringilla coelebs and Coccothraustes coccothraustes. Frogs Rana arvalis and R. temporaria as well as insects Dytiscus sp. and Melolontha sp. were also present in the food remains. The species composition and the number of small mammals preyed in Šakiai district were compared to the respective data from Kėdainiai district, Kurtuvėnai Regional Park and Kamanos Strict Nature Reserve. The diet of the Tawny Owl in Šakiai district differed in comparison to the Kamanos Reserve (more C. glareolus, less Microtus and shrews), Kėdainiai district (less shrews) and Kurtuvėnai Regional Park (a less share of secondary prey species).