Age and seasonal variations of the fur color in the bank vole

Age and seasonal variations of the fur color for five populations of the Bank Vole, inhabiting Tver region, have been analyzed using a novel methodic approach. As a result of comparing of three age groups by two standard color indexes, the age variation has been revealed. It was more pronounced for the index of whiteness. Seasonal variations of the fur color are expressed through the increase of mean values of whiteness and tint indexes.