Fitness effects of ecotourism on an endangered carnivore

Nature-based recreational and tourism activities can exert significant direct and indirect impacts on wildlife, through behavioral, physiological and distributional changes. Despite many studies demonstrating such changes, few attempts have been made to quantify the fitness consequences and evaluate their biological significance. Helagsfjallen in Sweden is a core area of the endangered Fennoscandian arctic foxVulpes lagopus, and a popular area for recreational tourism. Some dens in the area experience daily disturbance from tourism during the summer season, while others are virtually undisturbed. We used a long-term dataset (2008-2017) of 553 juveniles in 74 litters to investigate summer juvenile survival, which is an important fitness component for the arctic fox. We found that the mean juvenile survival rate increased from 0.56 at undisturbed dens to 0.83 at disturbed den during years of decreasing small-rodent abundance, where predation on the arctic fox is presumed to be highest. We suggest that the increased survival could be mediated by a human activity-induced predator refuge for the arctic foxes in close proximity of trails and mountain huts. Our study demonstrates a possible positive indirect effect of nature-based tourism on wildlife and is one of a few studies attempting to quantify this impact. It highlights the importance of context for how animals are affected by disturbance. We also demonstrate that studying how the effects of tourism activity vary depending on the context could provide opportunities for identifying the mechanisms behind these effects, which can be an important link between scientific research and the management of wildlife and tourism activities.