Altitudinal distribution of alpine Marmot (Marmota marmota) in the Pyrenees, Spain/France [Répartition altitudinale de la marmotte alpine (Marmota marmota) dans les Pyrénées].

Résumé

The alpine marmot occupies areas ranging in altitude from 1300 to 2800 m in the Pyrenees, although 67% of the colonies are found between 1800 and 2400 m. Greatest colony density and greater areal use than expected were found between these last limits. The lower edge of the altitudinal range normally coincides with current forest limit and the upper edge seems to be related to the availability of sufficient food as to accomplish its minimum annual cycle (maintenance, reproduction, and fat storage). There is a positive correlation between the number of colonies and the duration of the available food period above 1800 m. In a broad sense, the altitude range of the alpine marmot in the Pyrenees is similar to that in the Alps. Because the natural forest limit seems to be higher in the Pyrenees than in the Alps, the success of the introduction of the alpine marmot in the Pyrenees could be probably due to the existence of a wide supraforestal open area artificially created for pastoral use.