Baïbak antropogennikh landjaftakh Rostovkoï oblasti [Marmota bobac dans les paysages anthropisés de la région de Rostov. Marmota bobac in anthropogenic landscapes of the Rostov region].

Résumé

Marmota bobac, disapeared almost totally in the mid of the XX century, became the background species of the north-western part of Rostov Region again from the beginning of 70s (Kazakov, Sidelnikov,1989 et al.). Our researches in 1989-92 showed that in the most parts of Chertkovo District the marmots colonized all habitats favourable more or less with the high density (0,75+30% animals/1 hectare): 1) Conservated natural steppic areas and their pasturable modifications. 2) Fields of the food-grass and the technical crops and some fields of the wheat. 3 ) The ground buildings (doms, hills of the silos a. o.). 4) The areas of deserted villages and the borderlands of the habitable ones. 5) Protective areas around some technical objects. Three last types are connected with the technogenic elements of the landscapes and constitude almost 10-15% of the total area of marmot habitats. Their originality is determined by the predominating of the weeds and by the mezo-relief dissected in high degree. The population density of marmots in sich is often 1,5-2 times more than in the natural ones. For example, in the village Krynichnyi deserted in the end of 70-s, we observed in 1992 21 families (not less than 65 animals) on the area about 20 ha. The same areas were populated: in the natural steppe association- by 15 families, in the pasture-by 17 ones. Every dam 0,3-0,5 ha in area is populated by 1-2 families. The marmots density in the agricultural fields is on the country in average about ten times lower than in natural habitats. High density of the marmot populations in the technogenical habitats is connected with the concentration of the conditions and ressources which are necessary for the marmots - first and foremost the food and the refuges. Probably the weeds make possible to use the smaller pasturable areas. The anthropogenic increasing of the territory unhomo-geneousness stimilates the burrow-building activity and makes better the audio-visual communications by using of "substitutive butans"*. The same regularities were observed earlier for other regions (Semago, Ryabov, 1973; Abelentsev, 1975; Zimina, Bibikov, 1978; Deozhkin, 1986; Tckarsky, Brandier, 1990). Studiing of the pecularities of the marmot populations in the technogenic habitats can allow to define the reserves of environmental resources stimulating the integrational processes in populations and can help to worn out some alternative lines of the protection and utilization of the marmots resources in agro-landscapes. "butan"- marmot- created hillok