Ornis Hungarica. vol.8 Suppl. 1.. (1998) p.87-93.
The variation according to weather conditions in the food of the Long-eared Owl (Asio otus)
I examined the food composition of Long-eared Owls (Asio otus) wintering in Budapest, Hungary. The analysis was made on owl pellets collected weekly in Mityásföld in the winter of 1992/93 and in the New Cemetery, Kispest in the winter of 1993/94. Prey remains and their numbers were identified, and rour characteristics were evaluated: the number of species in the diet, the proportion of Wood Mice (Apodemus spp.), of Common Voles (Microtus arvalis) and of birds. These were compared with the following weather parameters: daily mean temperature at both ground level at at 2 m height, cloud-cover, daily mean wind velocity, proportion of windy hours in the night, mean daily precipitation, proportion of wet hours in the night, mean thickness of snow cover. The number of species in the diet positively correlated with the mean temperature measured at the ground level, no other correlation was significant. The proportion of birds was negatively, while that of proportion of Wood Mice - but not common voles - was positively correlated with the mean daily temperature. The proportion of Common Voles and Wood Mice were negatively correlated to the daily precipitation.