Long term dynamics of space and summer resource use in the alpine marmot Marmota marmota L.) [Dynamique à long terme de l'utilisation des ressources spatile et d'été chez la marmotte alpine].

Résumé

An alpine marmot’s home range is a structured portion of soil, vegetation and rocky outcrops. The dynamics of home range and resource use were investi- gated in Marmota marmotaL. at Gran Paradiso National Park, south-west Alps, Italy. Data were collected during 8 years from 73 individually known marmots, occupying three adjacent locations, in 264 hr of scanning and 551 hr of focal animal sampling. Three different locations did not differ in the total dimension of the home range but they differed in the total dimension of pasture. The home range inherited by immigrant monogamous couples supplanting the unrelated previous groups did not contract, and the dimension were not dictated by immediate feeding necessities, thus suggesting that in some way alpine marmots may envisage future needs. The main burrow systems and hibernacula were inherited by the new couples as well, while the spotting/resting points and other burrows varied across years and groups. The capability of the alpine marmots to maintain stable home ranges across years is unique in the marmot genus, and should be ascribed to common use of space and common defence in kin social groups.