Should I be worried about bears?
Yes.
Thats the short answer.
Often we feel bear warnings are too strident. But in this Park you have a fairly high probability of a sighting, even an encounter.
In Glacier the risk of bear attack might even be higher than the risk you take driving an automobile to get to the Park. Take every precaution. Do not leave your food unattended to make a sidetrip from the main trail.
Plentiful bear scat is a potent reminder. (We are convinced Rangers shovel it on to the trail.)
Our Safety page has more bear information.
Should I hike the Canadian Rockies instead?
There is terrific hiking a few hours north of Waterton. Consider Assiniboine, Sunshine or Robson as just-as-good alternatives.
Hike Glacier & in Canada both, if possible