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Qualitative observations of owls were carried out in the Polish Tatra Mts, S Poland in the years 1998-2003. The following six species were recorded: Eagle Owl, Tawny Owl, Ural Owl, Pygmy Owl, Tengmalm’s Owl and Long-eared Owl. The distribution of particular owl species in the Tatra Mts is clearly associated with changes in the habitat according to the altitude. Records of the Tawny Owl predominate in the lower montane zone, those of Tengmalm’s Owl in the upper montane zone, and of Long-eared Owl at higher altitudes (timberline and above).
Tho diet of Tawny Owl as a function of urbanization was studied in Central Poland in 1976-1984. The pellets were collected from 24 sites in habitats along an urbanization gradient ranging from the large, relatively undisturbed Kampinos Forest (1441 prey items), through small woodlots surrounding Warsaw (686) and into the city of Warsaw (2567). Diet varied due to urbanization: the proportions of mammals and amphibians were lowest in the city center (respectively 11.3% and 0%), but the proportion of birds, largely House Sparrow Passer domesticus increased from 2.9% in the forest to 88.7% in the city. Niche breadth and seasonal variation declined with urbanization. Relationships between diet composition and habitat structure of owl's hunting range in the city, as well as on the seasonal diet variation from owls hunting in forests, let to conclude that the owls were able to exploit locally abundant prey from a variety of habitats. Although the highest densities of Field Mouse Apodemus agrarius were noted in parks and cemeteries, our data suggest that Tawny Owls catch this species more effectively in small gardens and secondary growth areas. The predation on Field Mouse by a pair of owls breeding in an urban cemetery was low. Approximately 3.2% of the population were removed by the owl predation, considerably less than in a more rural population.
The fossiliferous Upper Varswater Formation at Langebaanweg (South Africa) produced remains of at least five species of owls (Strigiformes). Tyto richae sp. nov. is the first palaeospecies of Tytonidae described from an African fossil site, though indeterminate remains referable to the genus Tyto are known from the Middle Miocene of Morocco, the early Pliocene of Ethiopia, and the Pliocene of Tanzania. Athene inexpectata sp. nov. is not only the earliest documented fossil evidence for the genus worldwide, but also the first record of a species of Athene in Africa south of the Sahara. Proportions of its hind limb indicate that At. inexpectata sp. nov. probably has been as terrestrial as its modern relative At. cunicularia. A few additional remains represent the earliest fossil evidence for the genera Asio and Bubo on the African continent, though the poor preservation of these bones prevents more detailed identifications. A distal tibiotarsus of a small owl about the size of At. inexpectata sp. nov. indicates the presence of a fifth, as yet indeterminate, species of owl at Langebaanweg. Biogeographical and palaeoecological implications of this assemblage of owls are discussed.
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