Cascading effects of humans, through wolves, in a multiple land use ecosystem

Wolves (Canis lupus) have strong influences in terrestrial food webs through predation. Depending on the land use type (e.g. ranching, forestry, oil and gas), humans influence wolf density and distribution. We tested whether human activities affect predator-prey interactions and herbivory in a food chain in Southwest Alberta, Canada. We estimated human distribution using digital camera traps (n = 55). We obtained Global Positioning System telemetry data from wolves (n = 16), elk (n = 110) and cattle (n = 31). We calculated resource Selection Functions using Generalized Linear mixed models (GLmms) to test the spatial relationship between humans, wolves, elk (Cervus elaphus) and cattle and vegetation utilization (n= 148 plots) on the landscape. We found that while elk exhibited anti-predator behavior in response to wolf presence (i.e., drops in distance to cover, z=7.082, P<0.001, and in food quality of habitat used, z=4.454, P<0.001), cattle did not. Anti-predator response by elk confirms wolves can exert ecosystem effects through predation. by directly influenc- ing wolf density and distribution, humans may indirectly influence herbivory patterns of ungulates and ultimately, vegetation utilization. Such effects may be different depending on the land use activity. Poor anti-predator responses suggest that cattle are vulnerable to wolf predation and ensuing ecosystem effects are likely different compared to wild ungulates. Furthermore, predation on domestic cattle elicits intolerance by humans, generating a nega- tive feedback that maintains wolves at low densities