In search of the forest dormouse Dryomys nitedula Pallas, 1778 (Mammalia: Gliridae) in the Eastern Alps: which method is best?

The forest dormouse Dryomys nitedula Pallas, 1778 (Rodentia: Gliridae) is an arboreal and nocturnal small mammal species. This study assessed the effectiveness of different survey methods for detecting the elusive species at six study sites within the Alpine region of Terra Raetica (border area of Switzerland, Austria, and Italy), its western distribution limit. The aim was to establish a monitoring method for further studies on biology and habitat requirements of Dryomys nitedula . Methods compared included 90 wooden and 90 wood-concrete nest boxes, 45 tracking tubes, and 22 sites with wildlife cameras, each mounted at varying heights on trees. The forest dormouse was successfully detected using nest boxes, wildlife cameras and tracking tubes. Despite the higher effort required for transportation, installation, and maintenance, nest boxes showed high potential for ecological studies and long-term monitoring, especially when mounted above 2 meters. Wildlife cameras proved particularly suitable due to their low maintenance and long-term applicability, while tracking tubes offered advantages such as low cost and suitability for citizen science projects. In addition to fieldwork, public relations are a useful complement for discovering new occurrence points. Therefore, the study recommends combining multiple methods tailored to the specific research question and a minimum monitoring period of two years to achieve reliable results.