The paper contains information about ixodid mites of the Khanty-Mansi Autonomous Okrug - Yugra, obtained during expedition work in 2006-2016. Ixodes persulcatus dominates in the structure of the population of ixodid ticks. The list of small mammals serving as feeders of ixodid ticks is indicated. The highest indices of occurrence and abundance of ixodid ticks were introduced for Myodes rutilus and Craseomys rufocanus (28,6 and 25,0%, 0,8 and 0,9 respectively). Researches in Nizhnevartovsk region in 2016 confirmed the opinion about total absence of ixodid mites on flooded part of the floodplain because of usual overflows. All ixodid ticks are registered in rodents and shrews on mainland part. The same feature in location of ixodid matis in 2013 was observed in surroundings of Khanty-Mansiysk city. The paper contains the information about distribution of ixodid ticks on feeders in Nizhnevartovsk region.

Surveys of small mammals (insectivorous and rodents) and their ectoparasites were carried out in the Subpolar Urals (eastern macro-slope) near Mount Neroyka (Berezovsky district, Khanty-Mansi Autonomous Okrug Ugra) in different altitude zones (from 407 to 1018 m above sea level) in 2020 and 2021. A total of 15 species of parasitic gamasid mites, 1 species of ixodid ticks, 11 species of fleas and 1 species of lice were identified. Two counting methods, ditch with pitfalls and trap-lines, were used to better reveal the composition of small mammals (feeders of ectoparasites). Specific parasites of Eurasian water voles, Laelaps muris and Hyperlaelaps amphibius, dominated among gamasid mites regardless of the method of trapping insectivores and rodents. At the same time, the proportion of the Eurasian water vole in the small mammal community of the Subpolar Urals (eastern macro-slope) did not exceed 7%. The group of dominant species also included Laelaps algericus, which was recorded in only three species (of 16 small mammal species recorded in the Subpolar Urals): the Eurasian water vole, the field vole and the Middendorff's vole. Among rare species of gamasid mites, Haemogamasus dauricus is of particular interest, a species not previously recorded in the Urals and Western Siberia. Ixodes persulcatus is a single occurrence in the area. The find of this tick is one of the most northerly in the Asian part of the Russian Federation. Among representatives of flea and lice groups the share of specific species (shrews and red-backed voles) is high. This is probably due to the high mobility of shrews, their close contact with rodents, and the specificity of animal counting methods.

The purpose of the research is establishing the composition, infection rates, species and group ratio of ectoparasites of the East European vole on the northern border of the range in Western Siberia (Middle Ob Region). Materials and methods. In 2015–2018, in order to capture the provider of ectoparasites, the East European vole, we used methods of trap lines, trap trenches, and fence-traps; we recorded 173 animals from which we collected 881 specimens of gamasid mites, ixodic ticks, lice and fleas. To assess the quantitative indicators of ectoparasites, the indices generally accepted in parasitology were used. Results and discussion. In 2014, it was established for the first time that there is a sibling species of the common vole, the East European vole in the Middle Ob Region (middle taiga of the forest zone of Western Siberia). In the city of Surgut and its neighborhood, this animal is confined to the most transformed biotopes. The ectoparasite complex of the East European vole includes 26 species of parasitic arthropods. By the number of species (13) and individuals, gamasid mites predominate, and the proportion of ixodic ticks, lice and fleas put together is almost 3 times lower. In a climate of the Middle Ob Region, the list of ectoparasites will no doubt grow as the range of habitats expands and the contacts of the East European vole with other small mammals increase, and its role in maintaining pathogen circulation of natural focal infectious diseases will increase.

Abstract. There are 25 specially protected natural areas of various status have been organized on the territory of the Khanty-Mansiysk Autonomous Okrug Ugra. Despite their great nature conservation value, the degree of study of flora and fauna, as well as the ecology of plants and animals in the territory of most of them, remains relatively low. Until now, special studies of small terrestrial vertebrates inhabiting the Cheuskinsky Bor have been carried out. In 2020, our research of small terrestrial vertebrates were carried out. The purpose of the study is to identify the species composition and some features of ecology (abundance, biotopic distribution) of small mammals, amphibians and reptiles. The research was carried out in July-September 2020. Metal cones were used to catch most of the vertebrate species. A total of 7400 cone-days have been worked out. 10 species of small mammals and 3 of amphibians are registered. The species composition of small mammals at the Cheuskinsky Bor site is relatively poor, 10 species were captured by cones, 3 were marked visually. The group of dominants included the common shrew and the red-backed vole. They accounted for 22% and 77%, respectively, of all recorded animals. Reptiles in the 2020 season were not registered in the counts, however, according to the literature, the habitat of the common European adder and viviparous lizard is known. Among amphibians, the moor frog and Siberian salamander are rare, the European toad is common. In the future, when conducting annual studies, the list of small mammals can be supplemented by 714 species of insectivores, bats and rodents, the list of amphibians 1 species.