It's been a busy year for bear sightings in Canmore, Banff and Lake Louise — and it could be linked to the extra cold winter.

Grizzly bears have been making their presence known on the campgrounds and along highways, causing Parks Canada to issue two bear warnings near the Banff townsite and at Two Jack Lake campground. According to one bear biologist,that increase in bear activity can be blamed on the later-than-average spring thaw.

Click the audio player below to listen to the full interview from CBC's The Homestretch

"We've definitely seen a heightened level of bear activity this spring," said Sarah Elmeligi, who is working on a doctorate degree about how bears and humans use the Banff trail systems. "That's largely due to a really late snow pack melt in the upper alpines. In the spring time, grizzly bears come down to the valley bottom because that's the first area to green up and that's where the food is.They've just actually been hanging out there longer than usual, waiting for the snow to melt up high."

Several trails have been closed due to bear activity and Elmeligi says it's unusual to see that at this time of year.

Parks Canada doesn't normally close trails when grizzlies are around, preferring to issue warnings instead.

Bears under a lot of stress

Part of Elmeligi's research involves surveying visitors with hikers to assess their support for things like trail closures and she says early results suggest hikers do support closing trails when bears are in the area.

However, she says there is also a need to weigh the area's role as a way of maintaining ecological integrity with its role as a place for people to enjoy the great outdoors.

Elmeligi says it's also important people are mindful of the stress human interaction can cause for bears, particularly smaller or younger bears.

"Especially when we've got these young bears living around the Town of Banff, they're also being displaced by other larger bears, so they're just living a really stressful life out there, running into people, running into bigger bears.

Everybody's trying to chase them off and so it's part of our role I guess, as recreationists and as residents of the Bow Valley, to give these bears the space that they need."