Hjortdjurs (Cervidae) nyttjande av och beteende vid saltstensplatser i norska fjällen

Sammanfattning: Saltlicks are a common management practice for both wildlife and farm animals. In the Norwegian mountain areas these are typically intended for sheep on summer pasture but are used frequently by wildlife such as deer and reindeer. In 2016 the first European case of chronic wasting disease (CWD) was found in reindeer in Nordfjella, Norway. CWD is a prion disease that causes brain damage and eventually death that is previously known from North America where multiple species of deer have been affected. Though other species of Cervidae are thought to be susceptible, CWD has so far only been found in reindeer in Norway. Saltlicks, with their high animal-density and overlap of groups and individuals are thought to be a possible contamination hotspot and a project was started as part of an action plan following the CWD findings. Wildlife cameras were placed at multiple saltlicks, providing picture material to find possible contamination routes and future management strategies. The purpose of this project was to examine the presence and behaviors of deer at the saltlicks to further investigate the spread of infection both to and from individuals. First, the pictures were sorted by area, camera, date, and species occurring. The pictures containing deer were then further sorted and labeled with specific species, group size, sex and age, and behavior. A quantitative study investigating the overlap between sheep, reindeer and other deer was also presented. The results show that deer perform behaviors at the saltlicks that can contribute to the spread and exposure of CWD, such as ‘head to ground’ where an exchange of infectious agents can occur. However, the results also show that reindeer and other deer largely utilize different saltlicks, indicating less overlap between reindeer and deer than previously thought. In theory this mean that deer are more protected against the disease than if they were to visit the same saltlicks as reindeer. Further research on species susceptibility of CWD and possible control measures is needed to better understand the possible effects of the disease and how spread can be prevented.