The range of Tyto alba overlaps with that of Asio otus in a large part of the Holarctic. Both species are adapted to open-area hunting and prey upon similar species. In contrast to A. otus, data about the diet of T. alba on Crimea and surroundings are extremely scarce. Our study aimed to describe the prey spectrum of T. alba and evaluate at what extant its diet overlaps to that of A. otus. We evaluated diets based on 48 pellets of T. alba and 88 of A. otus collected from January to March 2018 in the Western part of the Crimea Peninsula. Simultaneously, we assessed the availability of small mammal prey by installing 150 spring-loaded bar mousetraps around the collection sites. Small mammals were the main prey in the diet of T. alba and A. otus (99.2% and 100% of all individuals in pellets). The most consumed species of both species was Microtus socialis (52.3% and 74.4% of all individuals). The second most consumed species of T. alba was Crocidura leucodon, an endangered species in Crimea. The diet of T. alba was more diverse than that of A. otus (Shannon diversity Index: 1.1 and 0.76, Simpson Index: 0.51 and 0.31, respectively). However, their diets overlapped widely (Pianka's index = 0.94). The frequency of mammalian prey in traps correlated moderately with that in A. otus pellets (r s = 0.5, p < 0.2), and it deviated from the frequency of mammalian prey in T. alba pellets (r s =-0.05, p < 0.9). The presence of the endangered C. leucodon in the diet of T. alba reinforce the utility of this predator species as a tool to detect threatened or rare small mammals that are not caught by traps and to increase information about their geographical distribution.
Variation in Common Blackbird, Turdus merula (Passeriformes, Turdidae), Nest Characteristics in Urban and Suburban Localities in Crimea. Kucherenko, V. M., Ivanovskaya, A. V. -Blackbird Turdus merula is a model species for studying the impact of environmental factors on the form and structure of nests. In the middle of XX, this species began to expand its range into the artifi cial forests of the Ukrainian steppe zone. Th is expansion may have led to changes in bird behaviour, including changes in nest construction choices (e.g., nest shape, size, location and building materials). In this study, we investigated Blackbird nest diversity (i. e., size, volume, and composition) in the park of Simferopol (a city in Crimea, South Ukraine) and in an artifi cial forest located nearby. We found a signifi cant inverse relationship between nest placement height and external nest diameter. External nest depth was greater in the forest than in the park. Th is diff erence refl ects the variation in plant life form between the sites. More specifi cally, nests in trees have signifi cantly greater external depth than the nests located on shrubs. Most nests in both urban and suburban localities contained natural and anthropogenic materials; there was no signifi cant diff erence in component types between sites. In general, the anthropogenic materials played a decorative role and also served as camoufl age.
In the article is analyzed own field data of the authors and scientific publications on the wintering of Anserinae in the Azov-Black Sea region of Ukraine in 1900–2017, but the main data was obtained in frame of international mid-winter counts (IWC) in 2005–2017. It was found that 9 species of Anserinae occur in this region during the different seasons of the year: Anser anser — nesting, wintering and migrating; Rufibrenta ruficollis, A. albifrons, A. erythropus, A. fabalis — migrating and wintering; Branta canadensis, Branta leucopsis, Branta bernicla, Chen caerulescens — vagrant or birds which flew away from captivity (zoo etc.). Eulabeia indica — is possible vagrant species. The most numerous wintering species is A. albifrons, common — Rufibrenta ruficollis, not numerous — Anser anser, the other species are not met annually and registered in a very small number. There was almost tenfold drop in number of wintering geese in the Azov-Black Sea region of Ukraine during the period of counts. The main reasons of such reducing of geese amount are the followwing: weather and climate conditions, changes in the forage acessibility, hunting and poaching pressure, poisoning as a result of deratization of agricultural lands, and from 2014 — the militarization of the Syvash area and stop of water supplying of Crimea through the North Crimean channell. It is likely that the factors mentioned above led to relocating of wintering areas of Anserinae, and resulted in decreasing of their amount in this region.
The winter roost of the long-eared owl Asio otus in Crimea (South of Ukraine), located in Simferopol, is described. In 2015-2017, the number of long-eared owls varied on a convex curve, with the maximum reached at the end of November and in December. The birds exhibited a strong preference for roosting in conifers, where we recorded 89% of the owls. There was an inverse relationship between the mean of the maximum daily temperature ( • C) and the number of owls in both seasons. The owls were not sensitive to abrupt but short-term temperature changes, but the temperature decrease curve caused practically synchronous changes in the dynamics of bird numbers. It was found that the number of owls significantly differed based on weather conditions in 16 trees. The proportion of owls sitting on coniferous trees increased with unfavourable weather, and the converse pattern was observed for deciduous trees.
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