Decreased cortisol among hikers who preferentially visit and value biodiverse riparian zones.

While outdoor recreationists often report increases to their well-being for time spent in nature, the mechanisms through which local ecologies affect human health have been difficult to quantify, and thus to manage. We combine data from pre-post salivary cortisol measures, GPS tracks, visitor photos, and surveys from 88 hikers traversing several types of landscape within peri-urban public lands in southwest Idaho, USA. We find that time in biodiverse riparian areas and areas of perceived aesthetic value correlates with decreases in salivary cortisol and improved well-being for hikers. Wildlife sightings were not associated with changes in salivary cortisol, but were associated with riparian travel and aesthetic preferences, indicating an indirect pathway for ecosystem services. Additionally, wildlife sightings decreased on high-use days, even though hikers did not perceive a negative impact of their recreational activity. These results suggest that cultural and physiological ecosystem services of nature depend on the ecological community of the area. Preferential visitation and high service value of riparian areas by hikers and wildlife alike target shared riparian areas as hot spots for management efforts to promote both ecological and human health within an increasingly urbanizing world.