Muskoxen (Ovibos moschatus) are an integral component of Arctic biodiversity. Given low genetic diversity, their ability to respond to future and rapid Arctic change is unknown, although paleontological history demonstrates adaptability within limits. We discuss status and limitations of current monitoring, and summarize circumpolar status and recent variations, delineating all 55 endemic or translocated populations. Acknowledging uncertainties, global abundance is ca 170 000 muskoxen. Not all populations are thriving. Six populations are in decline, and as recently as the turn of the century, one of these was the largest population in the world, equaling ca 41% of today’s total abundance. Climate, diseases, and anthropogenic changes are likely the principal drivers of muskox population change and result in multiple stressors that vary temporally and spatially. Impacts to muskoxen are precipitated by habitat loss/degradation, altered vegetation and species associations, pollution, and harvest. Which elements are relevant for a specific population will vary, as will their cumulative interactions. Our summaries highlight the importance of harmonizing existing data, intensifying long-term monitoring efforts including demographics and health assessments, standardizing and implementing monitoring protocols, and increasing stakeholder engagement/contributions.

Analysis the of cytochrome b gene (1140 b.p.) polymorphism and polymorphism of 79 specimens of the control region (934 b.p.) of mtDNA of the Siberian roe deer Capreolus pygargus from 23 regions of Rus

The extinction of large northern herbivores is a puzzle for many biologists. Is it caused by climate change or human activity? The survival of the weak trophic competitors promotes the “anthropogenic” hypothesis. The extant species of Pleistocene communities allow us to easily test this assumption. The reindeer and musk ox have been until now coexisting in the Arctic territory. Their island populations form a unique natural experiment for assessing the role of competition. On Wrangel Island, changes in their abundance occur with the opposite trends. The same situation recurs on other Arctic islands. The reindeer population decreases, while the musk oxen population becomes larger. We have found that the above trends are determined by the food web structure. The niche overlap between species is considerable and cannot be facilitated by habitat partitioning. The number of plant species in the musk oxen diet is higher than in the reindeer. The exclusive part of the musk ox diet was higher as well. The reindeer occupies a worse position in all of the habitat types. However, the changes in herbivores distribution during the Pleistocene demonstrate opposite results. Therefore, the competitive advantage could not save the Palaearctic musk ox, and its extinction seems to be the result of selective overkill. Conclusively, human activity may be considered as the main factor of the Late Pleistocene herbivore extinctions, and reintroduction of the musk ox should be coupled with extensive conservation.

Rangifer tarandus L. 1758 is one of the few modern hoofed species in which domestic and wild forms coexist in the same territory. The genetic differentiation of domestic and wild reindeer in Northern Eurasia was examined using microsatellite data. А total of 780 animals were studied at 16 microsatellite loci. Samples of wild reindeer were taken from seven populations inhabiting different natural areas, and samples of domestic animals were selected from the Evenki, Evens, Chukchi and Nenets breeds, including two ecotypes, Tofalar and Todzha reindeer. The levels of genetic diversity and variation in wild reindeer were higher than in domestic ones. Bayesian clustering analysis allowed us to distinguish domesticated reindeer populations by the degree of taming, but failed to detect differences in genetic structure between wild reindeer populations. These differences were found using the pairwise Fst values. Overall, the microsatellite analysis revealed a significant genetic differentiation between domestic and wild forms and the structuring of populations within each form, which may be important for the development of strategies for animal conservation.

Currently, the intraspecific taxonomy of snow sheep (Ovis nivicola) is controversial and needs to be specified using DNA molecular genetic markers. In our previous work using whole-genome single nucleotide polymorphism (SNP) analysis, we found that the population inhabiting Kharaulakh Ridge was genetically different from the other populations of Yakut subspecies to which it was usually referred. Here, our study was aimed at the clarification of taxonomic status of Kharaulakh snow sheep using mitochondrial cytochrome b gene. A total of 87 specimens from five different geographic locations of Yakut snow sheep as well as 20 specimens of other recognized subspecies were included in this study. We identified 19 haplotypes, two of which belonged to the population from Kharaulakh Ridge. Median-joining network and Bayesian tree analyses revealed that Kharaulakh population clustered separately from all the other Yakut snow sheep. The divergence time between Kharaulakh population and Yakut snow sheep was estimated as 0.48 ± 0.19 MYA. Thus, the study of the mtDNA cytb sequences confirmed the results of genome-wide SNP analysis. Taking into account the high degree of divergence of Kharaulakh snow sheep from other groups, identified by both nuclear and mitochondrial DNA markers, we propose to classify the Kharaulakh population as a separate subspecies.