Latitude- and climate-associated patterns in small mammal fauna changes of the West Yakutia

Distribution of small mammals has been analyzed on the territory of the Western Yakutia in the corridor between 112° and 116° E and between the Lena River valley (starting from the Vitim River mouth) and the Anabar and Olenyok interriverine area (59–71° N). The material was collected in 2002–2017 in 11 sites within the taiga zone (from the border between the middle and south taiga to the northern border of the north taiga subzone). A total of 11200 cone-days and 12500 trap-days were accumulated and 4200 specimens of small mammals belonging to 21 species were collected. The highest species richness of small mammals is registered on the border of the south and middle taiga (17–18 species). In the north taiga the fauna of small mammals is represented by 8–9 species. This decrease from south to north is uneven: in the river valleys the species richness is generally higher than in the watersheds. The penetration of taiga species to the north is of a larger scale than that of tundra species into taiga habitats; therefore, changes in beta-diversity occur mainly due to the distribution limits of boreal species. Besides, in the absence of geographic barriers, a sharp decline in species richness is observed between 65° and 66° N, which coincides with the boundary between the middle-taiga and north-taiga subzones. Out of the climatic factors, the distribution of small mammals is affected mainly by winter precipitation, winter duration, average July temperature and average annual temperature, while dependence on such factors as January temperature and summer precipitation was not found. How to cite this article: Volpert Y.L., Shadrina E.G. 2019. Latitudeand climate-associated patterns in small mammal fauna changes of the West Yakutia // Russian J. Theriol. Vol.18. No 2. P.99–106. doi: 10.15298/rusjtheriol.18.2.04