Bear G608 remembered for extraordinary 20,000 km range

Although Rob Gau has worked with many bears across the Northwest Territories, a handful stay firmly lodged in his memory. One of those bears is barren-ground grizzly Bear G608. 

Gau manages the biodiversity conservation section of the Department of Environment and Climate Change at the territorial government.

He shared the story of Bear G608 on the NWT Species Facebook page this week, nearly twenty years after the bear’s death. 

Gau met Bear G608 in 1995, when he was a graduate student at the University of Saskatchewan working with the GNWT’s wildlife division. 

She was about a four-month-old cub, fresh from the den with two brothers and her 19-year-old mother. She was tagged and tattooed, and assigned “G608.”

At that time, Gau was part of a project studying the habitat and landscape use, spatial movements and diet of barren ground grizzlies. 

Bear G608 was the healthiest out of the litter of three cubs, which was higher than the average bear litter size. 

“That means the mums are really, really healthy,” said Gau. “So, she had a good mom. She had a good teacher.”

While Gau says the researchers never recaptured her brothers, G608 and Gau met again in 2000, when Gau put a GPS-tracking collar on her. 

The encounter took place when Gau was working on a team studying how bears were interacting with mines and the roads being built during the diamond boom. 

He found G608 on her own, 40 kilometres from the mines. 

It was only once the collar started tracking the movements of G608 that Gau learned how special she was. 

“When we got the data back from G608, her movements were an order of magnitude larger than we found out for the male bears,” he said.

After some analysis, the team realized that G608’s home ranges for 2000 and 2001 were each bigger than some countries, such as Israel.

Israel, without the disputed territories of the Golan Heights, West Bank and Gaza Strip, is 20,770 square kilometres.

In comparison, male adult grizzlies have home ranges of 7,245 square kilometres, and females, 2,100 square kilometres. Subadult males – aged three to six years – clock in at about 11,400 square kilometres. 

“Of the over 250 barren-ground grizzlies tracked in the central Arctic,” wrote Gau in his post, “G608 has been the only female known to exhibit extraordinary periods of long-range movements. And the sheer magnitude of her movements in 2000 and 2001 eclipse those of any other bear ever collared in the NWT.” 

Gau told Cabin Radio that the size of her movements could have been her trying to find a home, or food. 

But in the end, she settled not too far from where she was born. In late May 2003, Gau saw G608 with two cubs of her own. 

The last time Gau saw G608 alive, her cubs were not with her. Shortly after that, her location stopped moving and they knew she had died.

Since then, G608’s life has stuck with Gau, who wrote up her story years ago but only shared it after being reminded of the narrative at a conference where his colleagues were discussing the effects of road infrastructure on caribou.

Gau said that he’s had the opportunity to meet many bears over his career, and quite a few stick out to him. “Each bear is pretty unique. Grizzly bears have unique personalities.” 

“Just knowing G608 from life to death was pretty unique in that way.”