Conservation officials are reminding outdoor enthusiasts to be careful in bear country this spring.

As the snow melts in Alberta's mountains, foothills and boreal forests, the sleeping beasts are coming out of hibernation — and they're hungry.

Mark Boyce knows firsthand how unpredictable an encounter with a 700-pound bear can be, especially if they're famished or feeling threatened.

"You don't know what kind of bear you're interacting with," said Boyce, an Edmonton researcher who has been studying threatened grizzly bear populations for more than a decade.  

"Most of them are very shy and will try and avoid you as best they can but you don't want to take your chances with a bear."

'They are highly unpredictable'

Boyce, a University of Alberta ecology professor, remembers one instance when he walked over a hill and almost "bumped into" a female grizzly, and then heard the telltale rustling of her cubs behind him.

He spent two hours detouring through the bushes in an attempt to get away.

A startled mother and her cubs can make for a dangerous combination.

"It's very exciting. It certainly catches your attention," Boyce said in an interview with CBC Radio's Edmonton AM.  "There is enormous variation from bear to bear and, as a consequence, they are highly unpredictable."

Females with cubs are often found in close proximity to humans because these habitats are the least attractive to older, aggressive males who will attack young cubs, said Boyce. However, mischievous young males are often the "biggest troublemakers."

"Mom kicks them out at about three years of age and they wander around, trying to make a living," he said.

"And oftentimes these males are being aggressively confronted by older males, so they're pushed from here to there and often into places they don't know very well."

The best way to avoid a bear encounter, said Boyce, is by not attracting them to you with anything that might smell like a meal.

Carrying bear spray, making plenty of noise and travelling in groups are also recommended ways to keep a safe distance.

"Garbage, dog food, even bird seed can be attractants for grizzly bears and most of the problems we have with bears revolve around some sort of attractant," said Boyce.

"If they smell you, they'll often run away, straight away but if there is any sort of food smell — that bacon you had for breakfast — that might be an attractant."

With files from Zoe Todd