Epsilon Archive for Student Projects

Abstract

Large predators have made a return in Europe in the past decades. In Scandinavia, the Eurasian Lynx (Lynx lynx) has expanded its distribution further south and recolonized past areas. Due to the recolonization, lynx management has become part of the public discourse in Sweden. One factor of this discourse is depredation on domestic sheep. My thesis focuses on the environmental factors affecting lynx depredation on domestic sheep as well as the effectiveness of lethal control to prevent secondary attacks on sheep in Sweden from 2009-2019. I used logistic regression to investigate the effect of environmental factors on the risk of depredation. Furthermore, I used Survival Analysis to estimate the effect of lethal control on repeated attacks. Between 2009 and 2019 there were a total of 760 depredation events of which 20.7 percent experienced a secondary event within one year. Most attacks occurred during October, while the least attacks occurred during March and April. On average 1.67 sheep were killed during an attack. Depredation events are linked to lynx density, roe deer density distance to settlement, artificial night-time brightness, ruggedness and proximity to water, indicating a “site” effect rather than “problem individuals”. My results support previous literature which suggests that lynx do not actively search for sheep farms, but rather encounter them by chance. The risk of a secondary depredation increased significantly with lynx density, roe deer density and distance to water. Hunting of lynx significantly decreased the probability of a repeated attack within one year by 60 percent. I conclude that mitigation measures should be focused on pastures which are far away from urban structure with rugged terrain and that lethal control is an effective measure for preventing future attacks in the short term, but its long-term effectiveness remains unknown. I encourage future research to investigate the connection between lynx depredation events and water proximity.