Snow cover and the climate severity influence on the common fox (Vulpes vulpes) behavioral adaptation

One of the ways to adapt to the changing parameters of the environment is behavioral adaptation. The paper presents data on the weather rigidity index use (G. Bodman) in environmental studies. The authors describe the behavioral characteristics of the common fox (Vulpes vulpes, Linnaeus, 1758) activity depending on the amount of snow cover and the climate severity in Krasnoarmeyskiy district of the Samara Region. Relatively low temperature and quite high wind speed influence the heat loss of the animal more than high temperature in calm weather. In scientific literature (A.N. Formozov, 1946, 1990) it’s noted that it is possible to use «weather cruelty» indicator that defines the conditions that contribute to frostbite. It is determined by low air temperature and wind velocity that particularly affect cooling objects that have excessive heat in comparison with the environment. However, A.N. Formozov could not use this indicator due to rather large deviations as the wind speed and the temperature on the investigated territory, as even in the same locality there is a discrepancy with the data of weather stations located remotely from each other, this author didn’t study habitats independently (A.N. Formozov, 1946, 1990, 2010). At the same time it is also noted that snowfall is an important factor, a powerful element of the environment that indicates what life forms can live in vast areas with snowy winter. Snow cover leads to seasonal migration or switching to food located above the snow.