Features of reproduction of the shrub vole <i>Microtus majori</i> Thomas, 1906 in natural conditions

Aim. The purpose of this research based on the study of the ecological and biological characteristics of the shrub vole is to expand knowledge about patterns of microevolution in space, ecology and biology on the basis of which to assess the adapted characteristics of the Central North Caucasian population of the shrub vole (Microtus majori Thomas, 1906) in natural conditions.Material and Methods. The material for this work was obtained during expeditions and stationary studies carried out by the authors in the Russian Central Caucasus from 2013 to 2017. During this time, a survey of various biotopes of the broad-leaved forest belt was carried out, taking into account both anthropogenic loads and the season of the year.Results. Stationary studies were carried out, taking into account the season of the year, in deciduous forest belt. Reproduction of shrub voles in the population studied takes place over five months (April‐August). Overwintered voles reproduce within four months (from early April to late July), females bearing three litters. Accordingly, we can say that the greatest importance in maintaining the viability of the population of this vole species falls on the overwintered yearlings of the first spring cohorts.Conclusions. The data obtained indicate the regular dynamics of the (seasonal) age structure of the population, associated with the reproduction and death of individuals of certain age groups. When conditions of existence in the population of the shrub vole studied change, it reacts with an increase in the intensity of reproduction, a seasonal change in the number of embryos in a litter, a change in sex and age structure: it is sensitive to any fluctuations in its habitat