Diet and reproduction in coastal and inland populations of the Tawny Owl Strix aluco in southern Finland

摘要: In generalist predators the energy needed for reproduction is derived from various prey categories, profitability of which may vary according to biomass or accessibility items. We examined relationships between diet and production young in two Tawny Owl (Strix aluco) populations southern Finland. found a positive correlation amount remnants different samples litter collected nest bottoms after breeding young. Three important categories owls during nestling period, i.e. Water Voles, Field Voles thrush-sized birds, seemed be significantly related number fledglings. However, only birds showed significant relationship fledglings when all variables were analysed together one model. The total mass was best predictor owl brood size. There no local differences effects on Our results, combined with some earlier findings, outline food supply With regards this can generalized other areas kinds within distribution range species. Similar outlines are probably applicable also many predators.