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The colouration of the underparts of the Barn Owl ranges in Europe from reddish-brown to white. This character, that shows a clinal variation, is thought to be a marker of subspecies identity. The subspecific identity or transitional state of a total 64 Barn Owl Tyto alba pairs was determined on the basis of their phenotypic characteristics. The present authors investigated the breadth of the transition zone in Hungary on the basis of the distribution of the white-chested subspecies and the transitional phenotype, and it was found to be at least 500 km wide. The width of the transition zone may result from the lack of preferences in mating pair choice. The observed pattern of phenotypic distribution is due to the marginal location of the studied population in the transition zone.
During the parasitological examination of the barn owl Tyto alba (Gmelin), from Mar Chiquita coastal lagoon in Argentina, specimens belonging to Synhimantus (S.) laticeps (Rudolphi, 1819) Railliet, Henry et Sissof, 1912 were obtained. Comparison of measurements of present specimens with Cram and Smogorzhevskaya’s description of the same species, revealed several dissimilarities in the metrical features which cannot be considered great enough to create a new species. This new record of S. (S.) laticeps represents the first citation of this nematode from South America, and contributes to the knowledge of the morphology of this species, giving complete measurements and a detailed description of spicules. In addition, morphological and evolutionary considerations regarding fourth larval stages and subadults of S. (S.) laticeps, are also presented in this paper.
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.
Feeding habits of three sympatric owl species in a coastal woodland of central Italy (Migliarino-S. Rossore, province of Pisa) were investigated by using the pellet analysis method. The prey availability in the field was also investigated by means of two live-trapping sessions carried out in three different habitats. S. aluco preyed almost entirely upon medium and large sized rodents, and the size of its mean prey was significantly higher than that of A. otus and T. alba. The diets of A. otus and T. alba appeared quite similar, but the former was highly specialised in preying upon small rodents, whereas the latter fed upon shrews as well as rodents. Live-trapping sessions showed that Microtus savii was the prey species most abundant in the open areas, while Apodemus sp. — in the wooded and bushy ecotonal areas. Principal component analysis suggesting that A. otus was more linked to open fields as foraging habitat, while diet of T. alba was more similar to small mammal assemblages in ecotonal areas. The diet of S. aluco was not associated with any given habitat, probably because its favourite prey (Rattus rattus) is a semi- arboreal rodent.
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