Three grizzlies that wandered into a family's rural back yard near Pincher Creek, Alta., on the weekend were simply hungry as they prepare for winter hibernation, a bear expert says.

The grizzlies appeared to show no fear as they repeatedly tried to get at some ducks in a pen next to the house, property owner Keith Lang told CBC News.

His daughter Kayla shot video as Lang shouted and honked his truck horn to try to scare the bears away.

But conservationist Kevin Van Tighem said there was nothing unusual about the bears' behaviour.

"They become very food obsessed. It's really all around gaining as much fat as possible, right before the winter," he said.

"That was actually a pretty healthy looking family of bears there."

Van Tighem said grizzly bears have become increasingly accustomed to humans, and that's not really a bad thing.

Grizzly bear interaction southern alberta

The bears were interested in the duck pen. The family says they acted with 'no fear.' (Kayla Furlotte/YouTube)

"As we improve our ability to co-exist with  bears, they become more comfortable co-existing with us. And I think the key point is, that does not make a dangerous situation," he said.

"Most grizzly bear attacks are defensive attacks from bears that perceive a threat. So, if they don't see us as a threat, that's actually a good thing, because they're less likely to attack."

Van Tighem said "it's just a matter of being realistic about where you live and what the risks are."

It's important to clean up food, and some people should consider an electric fence and carry bear spray, he said.