Parks Canada has closed several trails in the Skoki Valley area near Lake Louise after a grizzly attacked and killed a dog on Thursday afternoon.
Parks Canada says an adult grizzly bear pounced on a small dog as it walked beside its owner on a leash in the area and killed it.
The owner of the dog was not hurt in the attack.
Wildlife officials say that the bear was not tagged or collared and was previously unknown to them.
Parks Canada has closed off the area to the public and says the trail closures include the Skoki Lodge National Historic Site.
Wildlife officers with Parks Canada will continue to monitor the bear and its behaviour and movement over the coming days.
They say that bear attacks are rare but visitors should take all necessary precautions when in bear country, including carrying and knowing how to use bear spray.
Parks Canada also advises visitors to consider leaving their dogs at home when hiking in the mountain national parks and reminds owners that dogs must remain on leash at all times.
Visitors are reminded to report all bear sightings to Parks Canada Dispatch, 24 hours a day, at 403 762 1470.
