Courtship and use of mating areas by grizzly bears in the Front Ranges of Banff National Park, Alberta

In five of six observations of courting grizzly (brown) bears (Ursus arctos), pairs were isolated on a summit or upper-elevation ridge where the male repeatedly blocked the female's descent. These observations substantiate an earlier single observation of this mating behaviour. Similar isolation of mating grizzly bears on summits or ridges has not been reported elsewhere in North America. The habitat of the mating areas is described. The areas were not grizzly bear feeding habitat. Food intake evidently was reduced during the period of isolation. These observations are interpreted as male sequestering of an oestrus female and female testing of male vigour.