Denudation naturelle d'un terrier de marmotte de l'Himalaya, Marmota himalayam Hodgson (1841)
We have discovered a collapsed slope, in the thickness of which the Himalayan marmot's burrow Marmota himalayana Hodgson (1841) has been exposed. The denudation of the burrow is located in China on the North-West Plateau in the eastern part of Qinghai Province, south-south-east of Xining city (E 10Г56'; N 35°44'). Height above sea level is about 3100 meters. The denudation has opened underground passages of marmots and traces of ground plugs, with which marmots plug up tunnels during hibernation. The depth of the opened burrow is not less than 3 meters, but judging by the deepening tunnels, the burrow is much deeper. Probable cause of slope collapse is related to the properties of the soil accommodating the burrow and to the burrowing activity of marmots. Judging by the appearance of the collapse and the geographical location of burrow, the basic thickness of the soil is composed of loess material. The loess is characterized by vertical exfoliation (Kriger, 1965: 95). We suggest that the spread of the Himalayan marmot to the East is hampered by loess soil properties.