Alpine marmots in Austria: The present population structure as a result of postglacial distribution history [Les marmottes alpine en Autriche : la structure actuelle de la population est le résultat de la distribution historique postglaciaire].

Résumé

The present distribution of the Alpine marmot Marmota m. marmota (Linneaus, 1758) in Austria, the historical range during the Pleistocene, and recent efforts of re-introduction were documented. Autochthonous populations inhabit a continuous range extending over the western part of the Austrian Alps. Non-autochthonous populations occur in a more fragmented area of partly isolated massifs in the east. The non-autochthonous populations were generated by the release of only a few founder individuals (median = 5). The impact of founder effects and migration barriers on the structure of the disjunct non-autochthonous populations is confirmed by the genetic analysis of allozymes and VNTR-loci. Whereas autochthonous populations are characterized by high genetic similarity and common polymorphism, the non-autochthonous populations exhibit a more patchy pattern of variation caused by founder effects and subsequent drift. From the relationship indicated by the VNTR-patterns it appears possible to infer the putative origin of the founder individuals. In previous allozyme studies the genetic variability was found to be reduced with the exception of two widespread polymorphisms at the loci Pep-1 and Sod-1. A parasitological survey shows that Pep-1 genotypes differ in their degree of infestation by endoparasites (Citellina alpina and Ctenotaenia marmotae) indicating that this polymorphism may be maintained by selective foces.