CALGARY—If grizzly bears didn’t appear to be prominent in human-frequented spaces now, it’s definitely more likely they will be in the next 60 years — and human-caused climate change might be to blame, according to new research.

By 2080, an end-of-summer food staple for grizzlies in the Rocky Mountains — buffaloberries — will be more scarce in the weeks leading up to hibernation causing grizzlies to either not achieve a healthy body mass before winter or to go looking for food in human spaces, according to a study published Monday. That’s because the shrubs’ fruit could ripen three weeks sooner than usual. In the higher-altitude zones, the advancement of fruiting increases to 37 days.

“This is how climate change is going to impose itself on ecosystems. It’s not the big things that you would expect,” said University of Calgary professor Greg McDermid, a co-author of the report.

In the study, researchers showed that plant life cycles that are controlled by heat — such as the cycles of blossoming flowers or fruiting shrubs — can be tracked by satellite remote sensing using 45 observation points within Alberta’s Rockies.

It also used data from “hot boxes” — where different climates were simulated while growing buffaloberry shrubs — to forecast how climate change might predict their life cycle patterns in the future.

McDermid said that the warmer the temperature gets, the sooner the shrubs might begin to fruit. This could set off a chain reaction of events due to animals and other species not catching up soon enough or at all.

Read more:

University of Alberta research centre to track climate change’s affecting Canada’s mountains

‘Something has changed:’ Three bear species found in same northern Manitoba spot

Recent close encounters with bears show humans are too ‘cavalier’ around wildlife, says professor

“Animals don’t drown because of sea level rise. It’s subtler,” he said. “Not everything reacts to climate change at the same pace. So you get these mismatches happening. Plants react quickest because of their interesting dependence on temperature. And then other animals may not be so quick to react.”

McDermid predicts the early fruiting of the berry shrubs will change the behaviour of grizzlies, which are highly food-focused and will follow their noses to where food is available. It could result in more bears in human-occupied spaces, like campgrounds, where the animals often wouldn’t have been seen as much in the past.

It could have a big impact on grizzlies’ health too, since they gain much of their needed winter weight during those last weeks leading up to hibernation. In late summer, scientists have recorded individual grizzly bears feasting on as much as 200,000 berries in a day, their highest caloric intake of their diet.

Reproductive rates might also lower for Alberta’s large omnivores, since female bears that don’t have enough fat stores may not give birth at all.

The effects of changing plant cycles could circle back to the health of the plants themselves, such as the buffaloberries in Alberta, since pollinating insects might not emerge earlier with the shrubs.

Some of these changes to vegetation are already happening in parts of the world, McDermid said, which could be a precursor to western Alberta’s ecosystems.

For example, vegetation in Greenland has already begun to emerge earlier than usual and now the local caribou calving season has fallen out of step with the timing of the most nutritious forage. It’s these subtle changes indirectly caused by climate change that might be the most threatening to ecosystems.

“I kind of think that what’s happening with caribou in the North is a bit of a prelude to what we’ll see in, you know, places farther south as climate change deepens,” McDermid said.

The use of thermal satellite to analyze heat patterns could be applied to any ecosystem in the world (besides tropical climates) where plant development relies on a certain amount of heat accumulation to move on to its next stage of development, McDermid said.

Loading... Loading... Loading... Loading... Loading... Loading...

“I think we need tools that allow us to, you know, find those vulnerabilities or track these patterns. So that’s what I see the big contribution here for the science community,” McDermid said.

McDermid said he hopes a wider spread understanding of the subtle ecological changes that contribute to larger scale shifts in the environment might help inform policy-makers, as the globe heats up at a faster rate than species can evolve.

“The problem is that anthropogenic climate change is happening far quicker than is normal.”

Read more about: