POSSIBLE CAUSES OF DEPRESSION IN THE NUMBER OF THE GREAT GERBILE IN THE MATAIKUM SANDS

During the study of the territory of the Ustyurt Autonomous plague focus in 2020-2022. A sharp decline in
the number of the great gerbil was revealed. The depression in the number of the great gerbil covered about 19.0
thousand km2 of area, where contacts between rodents and their ectoparasites were disrupted, which led to a profound slowdown in the circulation of the plague pathogen in the populations of the great gerbil in this ecological
region. The sharp decline in the number of the great gerbil, according to our observations, is associated with the
action of two main factors: severe winter or dry summer. Increased mortality of gerbils, especially in settlements
on dense soils, is observed in harsh and snowless winters, when deep freezing of the soil occurs, although this does
not lead to a general depression in numbers. In the outbreak, the winter months were snowless and accompanied
by severe frosts, and the spring-summer months were absolutely without precipitation, with abnormal heat. Due
to a lack of food supplies, the number of great gerbils in the landscape-epidemiological region (LER) of the
Mataykum Sands has sharply decreased and depression is observed, which has led to a change in the population
structure.