SOME PECULIARITIES OF MICROTUS-SOCIALIS (RODENTIA) ECOLOGY IN CHERNYEZEMLI (KALMYKIA) IN INCREASING NUMBERS

Peculiarities of ecology and spatial and ethological structure of Micr otus socialis Pall. in Chernye Zemli (Kalmykia) during several seasons were studied. The vole's numbers are at the stable, relatively low le vel in spite of regular restoration of natural steppe vegetation. Anim als breed only in the period of vegetation. Significant spatial moveme nt of non-mature animals was observed late in spring, in the period of mass reproduction. These animals formed permanent pairs and occupied, as a rule, the same plot in summer drought. In winter the marked vole population in the sample areas (20 ha) was completely replaced, thoug h their numbers were preserved. After the fire in August, 1995 reprodu ction of voles started a month earlier than in the control. In the reg ion observed spatial and ethological structures in the vole population keep the common features, characteristic of these animals in the cent er of the range. The found variations are of adaptive character becaus e of severe natural conditions in Kalmykian steppe.