Effects of Wolf Presence on Daily Travel Distance of Range Cattle

The presence of gray wolves (Canis lupus) can directly and indirectly affect beef cattle (Bos taurus) production on rangelands of the Northern Rocky Mountains. While fairly extensive knowledge exists for the direct effects of wolf predation threat (e.g., cattle death and injury losses, elevated stress), our understanding of wolf-caused changes in cattle behavior and the associated cascade of potential indirect effects on cattle resource selection, diet quality, activity budgets, and energetic relationships is still largely in its infancy. We investigated whether wolf presence affected the daily travel distance of Global Positioning System (GPS) - collared cattle under a replicated, Impact-Control study conducted in western Idaho and northeastern Oregon during 2008 - 2012. Cattle in three Control (Oregon) study areas, where wolf presence was consistently low, traveled farther per day (13.7 ± 0.396 SE km day^-1) than those in three Impact (Idaho) study areas (11.4 ± 0.396 SE km day^-1) with moderate to high wolf presence. At Control study areas, cattle traveled farthest per day in July (13.2 ± 0.355 SE km day^-1) and were least mobile in October (11.8 ± 0.365 SE km day^-1), but daily travel distances were similar across all months for cattle in Impact study areas. This observational study provides evidence suggesting cattle in mountainous grazing areas alter their spatial behavior in response to gray wolf presence. These behavioral changes have energetic consequences that could potentially impact cattle productivity and ranch economics. Additional research into the activity budget and resource selection responses of these collared cattle is required to better understand the specific mechanisms behind these daily travel distance results.