People are urged to be extra cautious around elk for the next month and a half, when wildlife experts west of Calgary say the fall elk rut is in progress.
Male elks can behave aggressively, and unpredictably, toward people as they herd females for breeding until about mid-October.
Parks Canada warns that people can be putting themselves at risk if they don't give the animals enough space.
It recommends about 30 metres' worth, and keeping dogs on their leashes.
"[Bulls are] protecting their cows," said Blair Fyten, a wildlife coexistence specialist with Banff National Park.
"And if people get too close to the bulls, or if they get in between the cows and the bulls, then the bulls become aggressive."
Elk can gather near the outskirts of townsites because they can consider them a refuge from predators that include cougars and wolves, Fyten said.
But he said bull elk can be predators, too, when they feel they need to protect themselves.
"A bull elk uses its antlers when it attacks something," he said.
"There's that chance that you could get skewered … we've had really close calls in the past."
What to do to stay safe
Aggressive elk encounters can be triggered by people getting close to take photos — or unsuspecting joggers and cyclists that take them by surprise.
"We see people just getting too close, both from trying to sneak past but also trying to get that beautiful picture or get a nice selfie," Fyten said.
Leave them alone instead, and make noise when you're in grassy areas or on the trails.
And if one should act aggressive toward you, don't play dead.
Maintain eye contact, make yourself look bigger by waving a coat or jacket, and do what you can to get cover in or behind vehicles and buildings.
"If you do find yourself … on the ground, roll," Fyten said.
"Do whatever you can to get up and get away … because these bull elk will pin you to the ground."