Weather-Dependent Variation in the Winter Diet of Urban Roosting Long-Eared Owls Asio Otus in Pécs (Hungary)

Long-eared Owls (Asio otus) usually winter in groups in settlements, hunt at night and rest in evergreen trees during the day. From prey remnants regurgitated as pellets, one can detect species present in their hunting areas and changes in their abundance. Our aim was to reveal how the ratio of small mammal species in Long-eared Owl prey changes during the winter, since weather can influence hunting success and the availability of prey. There were 40–60 Long-eared Owls wintering in the city of Pécs. From November 2014 to mid-March 2015 we collected 6,328 pellets from which 9,087 prey remains were identified. 97.5% of prey consisted of small mammals belonging to 21 species. The diversity of small mammals in the pellets collected in November was significantly lower in comparison with other months. With the increase of precipitation, the relative abundance of the Common Vole (Microtus arvalis) and Common Dormouse (Muscardinus avellanarius) decreased, while that of the Striped Field Mouse (Apodemus agrarius) and Wood Mouse (A. sylvaticus) increased. In the periods when the area was covered by snow, the ratio of the Common Vole as prey continually decreased, probably because it stayed under the snow. Since the availability of the Common Vole declined, the proportions of the Striped Field Mouse and Lesser White-toothed Shrew (Crocidura suaveolens) as alternative prey grew significantly. In low temperature periods, Brown Rats (Rattus norvegicus) and birds are more often preyed upon. Despite the hunting area being predominantly urban, species preferring open grassland habitats were significantly more common. As winter progressed, the role of forest-dwelling species in the diet continuously increased.

Genetic characteristics of the common dormouse (Muscardinus avellanarius) using microsatellites in Lithuania

Population genetic analysis becomes more and more popular as a tool to use in animal conservation (Broquet, Petit, 2009). The common or hazel dormouse (<i>Muscardinus avellanarius</i>) is a member of the rodent family <i>Gliridae</i> (Juškaitis, 2008a). These rodents are vulnerable to natural habitat changes, and because of this monitoring of the common dormouse was carried out in many countries (Bright et al., 2006), but there is still lack of genetic data. It is well known that microsatellites are being used to investigate the genetic structure of natural populations (Balloux, Lugon-Moulin, 2002). In our study we used 5 microsatellite primers to investigate 17 common dormouse samples from different places in Lithuania and Latvia. For DNA extraction non-invasive hair samples were used. The results show that the Mav023 primer with 13 alleles is the most informative primer, while the Mav002 primer with 2 alleles is the least informative one. The expected heterozygosity (He) per locus was between 0.5 and 0.743, and the observed heterozygosity (Ho) per locus was between 0.463 and 1, except Mav005 with 0.257.