干旱区生态环境知识资源中心

The steppe theriofauna of the Volga-Ural interfluve has been changing during the past century under the effect of both natural and anthropogenic factors. These changes have manifested themselves most clearly in the desert Caspian steppes and the dry steppes of the Transvolga Syrt Plain. A total of 66 mammal species are listed for this region. Some of them have disappeared while others have appeared anew, with their abundance ratio fluctuating significantly. Over the past 50 years, 15 new species have been recorded in the Transvolga fauna. One-third of them have come from the south and represent the desert faunal assemblage, while two-thirds are representatives of the forest assemblage that have come from the north.