BANFF-JASPER – A grizzly bear has been out of the den wandering around Jasper National Park during southern Alberta’s unseasonably warm winter weather, prompting a 72-hour warning for a popular cross-country ski trail area.
Parks Canada wildlife experts say they are not sure if the bear is out of the den extremely early or actually never went in for the winter slumber, noting the bruin was first spotted on Jan. 6 near the Jasper townsite and last spotted in the park on Jan. 12.
“This is an unusual time to have a bear out and about for sure, so it's possible this bear has actually never been in the den,” said James McCormick, human-wildlife co-existence specialist for Jasper National Park.
“Looking at research that was done in west central Alberta and talking to colleagues in Banff, the latest they’ve ever seen bears going to den is sort of the third week of December and the earliest bears might come out of a den is the second week of February.”
After the grizzly bear was spotted near the Pyramid Bench trails, it was then seen on the hillside below the Jasper SkyTram. The following day the bear was observed in the area of the Pipeline cross-country ski trail.
Parks Canada issued a 72-hour warning for the Pipeline trail, but has since removed it. The grizzly bear was last seen in Jasper National Park on Jan. 12 and was observed travelling even further west on Jan. 14 in Mount Robson Provincial Park.
McCormick said the grizzly bear, at one point, appeared to be following a set of moose tracks that had blood in them.
"We thought maybe it's scavenging or looking for something,” he said.
“It’s still moving and it’s gone quite a distance."
The wildlife team has been scanning the research on bears abandoning dens.
“It usually tries to find another one fairly soon after and it doesn’t usually walk too far,” McCormick said. “That’s another thing that supports the idea that maybe this bear hasn't gone into a den yet.”
In addition, photos of the bear were sent to a wildlife vet to get a better idea of the animal’s health.
“He thought that the bear looked skinny, like it had lower than expected fat reserves, which could account for why it’s not in the den,” McCormick said.
“That’s not for sure, but maybe that’s part of the reason.”
Banff records third warmest December on record
Weather could also be playing a part in the bear being out and about. Jasper, like much of southern Alberta, has experienced unseasonably warm weather for the most part.
Banff, for example, experienced the third warmest December on record, according to Environment and Climate Change Canada, and while the first few days of January were chilly, temperatures started warming up to above normal again.
Stephen Berg, a meteorologist with Environment and Climate Change Canada, said the mean temperature for the month of December was – 9.2 degrees Celsius, but December 2024 was – 2 C.
“That’s about six degrees above normal for December from the 1st to 29th of the month… that’s very warm for that time of year,” he said.
“Banff was around the third warmest on record, out of 136 years of records.”
In addition, December was a dry month in Banff in terms of monthly precipitation, with very little snow in the valley bottoms in Banff National Park and neighbouring Canmore.
Berg said rain and the snow water equivalent was about eight millimetres in December, when normal for Banff is 33 mm in December.
“That’s quite a far departure from normal,” he said. “That’s the 14th driest December on the record.”
McCormick said Jasper’s weather conditions have been much the same.
“We’ve been probably parallel to what Banff has been getting; seems to be above normal temperatures and below normal snow cover, which might affect what the bears want to do,” he said.
“We haven’t seen any other bears sort of show up out of dens, though.”
Climate change impacting denning bears: study
A study, called Drivers of Hibernation: Linking Food and Weather to Denning Behaviour of Grizzly Bears, was published in 2016 in Behaviour Ecology and Social Biology, the first study specifically linking grizzly bear hibernation and climate change in Alberta, showing bears will likely have shorter denning seasons.
Conservation scientist Karine Pigeon and wildlife biologists Gord Stenhouse and Steeve Côté used 12 years worth of data from 1999 to 2011. They investigated dates of den entry and exit for 15 male and 58 female grizzly bears in the boreal forest and the Rocky Mountains of west-central Alberta.
Bears were captured with leg snares, culvert traps or darting from a helicopter.
Although hibernation for grizzly bears depends on sex and reproductive status, the researchers showed the timing of den entry appears to be also driven by food availability in fall while emergence from the den is more linked to weather.
Specifically, high berry availability was associated with late den entry, while low winter precipitation and high spring temperature resulted in grizzlies emerging from the den early, which have implications for the long-term conservation of bear populations.
“Climate-induced changes in the phenology of hibernation for bear species could result in altered energy budgets, reduced cub survival and fitness and increased human-bear conflicts,” state the researchers.
“Our results provide the necessary first steps to understand the potential impacts of climate change on hibernation behaviour of grizzly bears.”
The scientists found no link between fall temperature and grizzly bears going into the den, however, as expected suggested warm spring and reduced snow cover that are consistent with global climate model predictions reduce the length of the hibernation period by triggering early den exit.
“Our findings show that increasing average monthly maximum temperatures by only 2 °C and reducing winter precipitation by 20 per cent resulted in bears emerging from dens five days earlier,” they wrote.
Since 1950, data shows winter temperatures have increased by 0.5 to 1 °C per decade across the province.
Per degree of global mean temperature increase, projected changes from climate models for Alberta include a 2 °C increase in average winter temperature and 1.5 to 2 °C increase in average summer temperature.
The extent of spring snow cover in the northern hemisphere is also expected to continue to decrease in mid-latitude dry regions.
The study’s researchers noted evidence linking warm spring temperatures with early den emergence in yellow-bellied marmots and delays in coming out of the den associated with late snowmelt for Columbian ground squirrels.
“We can expect bears to emerge from dens earlier as the climate continues to warm,” they state.
The research suggested that temperature within the den may be a more relevant cue to grizzly bears coming out of the den, which could be associated with bears becoming too warm and seeking more optimal temperatures outside of dens.
The results showed that all females, regardless of reproductive status, were affected by weather conditions at the time of den exit.
“Early den exit by females with cubs-of-the year may, therefore, have repercussions on the condition of cubs at den exit because early den exit may lead to vulnerable cubs being out of dens sooner, thereby increasing infanticide opportunities or human-caused mortalities,” states the researchers.
“Still, early den exit is likely to positively affect body condition and cub development because of a probable increase in foraging opportunities associated with longer growing seasons and active periods.
The researchers found that changes in hibernation behaviour are expected with warm temperatures and reduced snow precipitation predicted under future climate conditions.
With humans the primary cause of grizzly bear mortality worldwide, they say climate-induced changes in hibernation behaviours may further increase human-bear encounters and potential conflicts.
“Grizzly bears and humans could be simultaneously active on the landscape for longer periods associated with unseasonably warm springs or autumns expected with future climate conditions,” they wrote.
The researchers say it is clear climate change is altering timing of spring green-up and the onset of winter, disrupting the seasonal behaviours of species, and can put additional strain on threatened populations, especially during energetically demanding periods such as hibernation.
“Our models provide the necessary tools to make empirically based decisions and policies aimed at mitigating future impacts of climate change on grizzly bear populations in Alberta, Canada, and our method can easily be adapted to populations elsewhere,” the researchers wrote.
Wildfires and denning
In Jasper National Park, grizzlies tend to den on subalpine or alpine slopes where it is colder.
The devastating summer 2024 Jasper wildfires did burn into the subalpine and alpine areas in some locations. In total, the fires burned more than 32,000 hectares.
McCormick said it is "a potential" that the fires could have impacted grizzly bear denning, however, grizzly bears are a wide-ranging species.
“We know that grizzlies can travel easily a good distance, a far enough distance to get out of that burned area to find a potential new den site,” McCormick said.
The wildfires, however, could have impacted black bear denning habitat, said McCormick, and may have created some unusual denning opportunities for black bears.
“They are less likely to dig a den so they might be in blow-down or something like that, so that might have changed,” he said.
“We did have someone kind of stumble across a black bear den here in the valley bottom, and that bear’s actually denned into what looks like an ash pit, into the ground, which is kind of unusual for a black bear.”
Bears emerging in spring
In the Bow Valley of Banff National Park, famed grizzly bear 122, a.k.a The Boss, is always the first out of the den.
In 2024, he first appeared on March 18 and the year before that on March 23.
The patriarch of Bow Valley grizzlies typically emerges from hibernation in March, but in 2020, he was out in late February – the earliest a grizzly bear had been recorded out of the den in Banff over the previous decade.
McCormick said the emergence of the grizzly bear in Jasper National Park in January, although extremely unusual, is a reminder that people can potentially run into a bear at any time of the year.
“There’s definitely a lower chance in the middle of winter, but we do ask people to consider carrying bear spray still … it’s also useful for other carnivores like cougars or wolves,” he said.
In national parks, it is also the law for dogs to be kept on leash at all times.
“Dogs will disturb bears,” McCormick said.
