Lobkov V. Intrapopulation regulation of numbers of mammals with the example of the spotted suslik (Spermophilus suslicus G?ld.) and other species

It is shown, that at changes in numbers of the spotted suslik and some other species of mammals depend on changes of spatial and qualitative structure of the population, birth rate and death rate, allowing assuming the common intrapopulation mechanisms of regulation of numbers. The increase in numbers is caused, first of all, with the increase of birth rate. It is observed in females of the first generation that were born during cessation of depression or during occupation of new places of dwelling. In following generations, birth rate decreases. Accordingly, annual increase of the population numbers changes. Changes of birth rate are caused by changes of spatial structures and population density under influence of external factors through physiological processes regulating reproduction. The hypothesis of formation of cyclic changes of numbers involving intrapopulation mechanisms of regulation of birth rate is offered. Examples of rapid increase in numbers or extinction of mammals, and dynamics of borders of their ranges, which can be explained by action of intrapopulation mechanisms of regulation of birth rate, are considered.