Usage de l'espace et du temps dans une population de M. marmota de l'Apennin septentrional. Space and time use in a population of Marmota marmota of the northern Apennines.

Résumé

From 1989 to 1992, an etological study on the introduced population of Alpine marmot has been carried out in an area of 5 ha where all the burrows were marked. For two-four consecutive days in alternate weeks from May to September, the position and activity of marked marmots was recorded every 15 min from dawn to dusk. The basic social structure is clearly identifiable as separate and territorial families. Both the families of the study area reproduced twice consecutively, afterwords a period of two or three years without litters followed. The two families reproduced alternately, from 1988 to 1993 we never observed the contemporaneous presence of yearlings in the two families. The quantitative assement of the use of any burrow let to identify a system of main burrows, a system of secondary burrows and scattered burrows. The adults and the youngs utilize all the systems of burrows, the yearlings concentrate their activities on some of those. The frequency of foraging increases from the burrows situated on higher and sleeper slopes (3%) to those digged in lower and flatter areas (46%). Nothwithstanding considerable demographic variations, there have been no significant changes in the extension and structure of the settlements.