American black bears perceive the risks of crossing roads

When black bears cross roads, their HRs increase, indicating heightened alertness to danger. Wildlife reacts to roads in various ways, but it is unknown whether road crossings are stressful. We monitored black bears with cardiac monitors and GPS-collars in Minnesota. On average, bears crossed a road once a day; their HRs increased when 100 m away, and increased more with higher traffic volume, but not enough to suggest roadway interactions were highly stressful.