Canadian climbing legend, Barry Blanchard was recently stalked and treed by a grizzly bear in the Lake Louise area of Banff National Park. Blanchard was guiding a client in the area when they noticed that they we being followed by the bear. The grizzly chased the pair up a tree and kept them pinned at the 25 m mark for over an hour. The grizzly eventually left and a park official armed with a shotgun escorted the climbers to safety. More details here.