Distribution of caribou and wolves in relation to linear corridors

Linear corridors (roads, trails, seismic lines, and pipeline corridors) have been hypothesized to increase human harvest and predation pressure on woodland caribou (Rangifer tarandus). We tested the hypothesis that linear corridors affect caribou and wolf activities by examining the distribution of 2,616 telemetry locations of caribou, 27 caribou mortality sites, 592 telemetry locations of wolves (Canis lupus), and 76 sites where wolves had preyed on large ungulates relative to linear corridors in caribou range and well-drained sites in northeastern Alberta. Of the 98 radiocollared caribou, 35 were significantly further than random from corridors and only 3 were significantly closer. The mean difference between caribou and random locations (106 m) was significantly different from zero. Within caribou range, wolf locations were closer (134 m) than random to linear corridors. Wolf predation sites were not significantly closer to corridors than were wolf locations or random points. Caribou mortalities attributed to wolf predation were closer (316 m) to linear corridors than were live locations from all caribou, indicating that caribou that are close to linear corridors are at a higher risk of depredation. Each caribou mortality attributed to wolf predation was closer to a corridor than their telemetry locations while alive (mean difference = 204 m), Caribou mortalities caused. by humans were 171 m closer to corridors than all live caribou locations, however this difference was not significant, increased industrial activity in caribou range could have a significant effect on caribou population dynamics by increasing predation. The development of new corridors within caribou habitat should be minimized and existing corridors should be made unsuitable as travel routes to reduce the impacts of industrial development on caribou populations.