Dependence of the Population of the Midday Gerbil (Meriones meridianus, Rodentia, Gerbillidae) on Provision of Forage Resources in Different Seasons of the Year in the Northwestern Caspian

In the conditions of the Northwestern Caspian Sea, the state of the midday sand lance population is determined by the dynamics of food resources. An important component of the environment that determines the condition of the midday gerbil is bush thickets, which serve as good shelter for the animals. It has been established that on a sand dune where a higher density of shrubs is noted, compared to open areas of the deserted steppe, the productivity of vegetation increases and the species composition of plants changes. The relationship between the gerbil population density and vegetation productivity was shown (R = 0.74, P < 0.05). In addition, the relationship between the number of gerbils and the productivity of bluegrass bulbs (Poa bulbosa) is shown, which fluctuated during the years of research in the sand dune area from 3.7 to 5.5 dt/ha of dry weight, and in the desert steppe area from 2.3 to 3.8 dt/ha. In accordance with the nature of the provision of food resources, changes in the number of midday gerbils were noted in different seasons of the year from four to 24 individuals/ha on sand dunes and from two to 14 individuals/ha in the desert steppe.