Oa. Ermakov et Sv. Titov, Dynamics of Spermophilus major (Rodentia, Sciuridae) range boundaries in the Volga River region, ZOOL ZH, 79(4), 2000, pp. 503-509
The southern border of the Spermophilus major range in the Volga River regi
on (areas on the left bank) has changed due to settling the animal to the s
outh. Spermophilus major inhabiting the Volga right bank is represented by
two different in origin populations which spread to the west. The expansion
of the S. major range seems to be caused both by warming and humidificatio
n of climate in temperate latitides and anthropogenic transformation of lan
dscapes.