Mountain ungulates and the conservation of scarce plant species: the cases of Delphinium montanum and Xatardia scabra

Abstract

In order to assess the possible negative influence of a high density population ofizard (Rupicapra pyrenaica) on the occurrence of several restricted range plants in the eastern Pyrenees, a monitoring experiment was carried out in the Cadí- Moixeró Natural Park and Game Reserve. Ungulates prédation upon reproductive parts of the plants is rejected as a factor influencing Delphinium montanum and Xatardia scabra population viability, even when high rates of consumption of flowers and fresh fruits are detected. Population dynamics of both plant species are mainly regulated by the habitat physical conditions and by intraspecific competition. Plantlet occurrence depends on the availability of bare substrate and is not related to seed production, nor the presence of ungulates. Plant density and age structure for these scree species rely on the limited availability of substrate resources, which leads to strong intraspecific competition.