Epsilon Archive for Student Projects

Abstract

In recent years, large carnivores have recolonised human-dominated landscapes after near extinction. As their populations recover, efficient monitoring has become a crucial part of management. In Scandinavia, various techniques are used for the annual survey of Eurasian lynx (Lynx lynx). This study investigated whether female lynx revisit specific locations in their home range for extended periods, and what habitat factors characterise these locations. These results could improve camera trap placement for the yearly monitoring of lynx family groups. GPS locations from 17 female lynx in periods between 2008 and 2023 were used to identify long-term GPS location clusters. A total of 214 long-term clusters were identified, with a minimum of three positions within a 100-meter radius, exceeding 96 hours from first to last position. Generalised linear mixed models (GLMMs) were used to analyse the effects of proportion of total forest, human infrastructure and water and wetland, distance to large and small roads, the index value of terrain ruggedness and habitat suitability on the position, on the probability of a lynx cluster compared to random position and lynx single position, which were locations that were not included in a cluster. The habitat suitability index was higher at lynx clusters compared to lynx single positions. Terrain ruggedness and total forest had a positive effect on the probability of a lynx cluster in the highest-ranked models for both datasets: lynx cluster – lynx single positions, as well as in lynx cluster – random positions. In contrast, human infrastructure had a negative effect on lynx clusters compared to lynx single positions. The long-term clusters were likely selected for safety as the lynx prefer forested and rugged terrain for protection. By analysing long-term clusters, it is identified that the lynx returns to specific locations with safe habitats. Camera traps could be placed in similar habitats which could enhance camera trap placement, ultimately improving lynx monitoring in Scandinavia.