Living in sympatry: Alpine mountain hares and European hares in times of climate change

In Sweden and Russia, a decline of the mountain hare (Lepus timidus) has been observed since the last century. Simultaneously with the decrease of the snow hare densities, an expansion of the brown hare (Lepus europaeus) in these areas has been observed. An investigation of the hunting statistics of Graubünden (Switzerland) provides evidence that the subspecies of the mountain hare (Lepus timidus varronis), which is restricted to the Alpine region, is being displaced by the brown hare at higher altitudes. On the one hand, the area available for the mountain hare decreases, on the other hand, the mountain hare seems to climb less rapidly than the brown hare. Moreover, genetic mixing with the brown hare has already been demonstrated for the rock hare in Graubünden. Both of these factors significantly worsen the situation for the mountain hare in the Alps. Although in the literature the main reason for the decline of the mountain hare is the dispersal of the field hare, there are practically no empirical studies investigating the coexistence of the two hare species. In this research project, we will test whether competition between the two lagomorph species in sympatry leads to possible niche separation in space use and food preferences. In addition, we are testing whether the amount of introgression is height dependent. GPS collars will be used to examine spatial and temporal space use. Food preferences and genetic integrity of both species will be determined with fecal surveys. In doing so, we hope to be able to draw conclusions about the nature of competition between these two hare species in a holistic approach. Translated with www.DeepL.com/Translator (free version)