Clean caribou, clean country

The Porcupine caribou herd can tell us a lot about the presence of contaminants like mercury and radioactivity in the Yukon. "They are our key indicator," said Mary Gamberg, a scientist with the federal northern contaminants program.

The Porcupine caribou herd can tell us a lot about the presence of contaminants like mercury and radioactivity in the Yukon.

“They are our key indicator,” said Mary Gamberg, a scientist with the federal northern contaminants program. “They’re definitively our canary in the coal mine.”

Gamberg has cleared the herd of any concerns stemming from the 2011 nuclear disaster in Japan.

“Air masses can move very, very quickly and we are in the air pattern where air leaves the eastern part of Asia and comes directly up to the Yukon,” said Gamberg.

This has been proven by an airborne-mercury testing program at Little Fox Lake that has linked increased mercury levels at the lake to the increased use of coal mines in eastern Asia.

For the caribou, the concern comes from the lichen.

“We were concerned that the air mass came up, dropped radioactivity on the lichens and lichens are like sponges and they absorb stuff from the air,” said Gamberg. “They’re very effective at absorbing radioactivity. And then, of course, the caribou eat the lichens.

“That happened after Chernobyl. Reindeer herds in Scandinavia were unable to be consumed for several years because of that exact situation.”

Licensed and First Nation hunters donate skeletal muscle, like parts of the caribous’ necks, to the program each year for testing, said Gamberg.

Samples for the radioactivity search were sent to a Health Canada lab to be analyzed for the harmful elements. Those results were then compared to the archive of samples from this herd.

Samples of lichens and mushrooms were also sent for testing and those results haven’t come back just yet, Gamberg added.

There is no simple or definite reason why the Yukon, and its animals, was not affected by the fallout of Fukushima, said Gamberg. Rainstorms over the ocean may have washed the radioactivity out, or perhaps there was a change in wind.

“There are so many variables that contribute to the transport of these contaminants,” she said. “It could be any number of things.”

“But we’re good now,” Gamberg added. “This was a one-time event. If it had travelled here and gone into the lichens, it would have stayed in the lichens and we would see it in the caribou and that’s not happening, so we’re all good.”

And on a whole, the territory is looking fine when it comes to contaminants that migrate through the air and water.

The federal contaminants program has been studying traditional foods in the territory for 20 years.

“We did bears, we did willow ptarmagin, we did fish, we did cranberries, we did willow bark – everything that people take from the land,” said Gamberg. “We found that in the terrestrial system, there’s really nothing to worry about.”

Eventually, the program started to focus only on caribou, moose and some fish.

Two years ago, moose were also taken off the list because contaminant levels were so low.

Now, only Porcupine caribou and lake trout are monitored.

For fish, the lake trout are the proverbial canaries, said scientist Pat Roach.

“If they’re OK, everything else is OK,” he said.

This is because in the Yukon, lake trout live the longest, breed until they die, and are top predators.

Contaminants, like mercury, really only start accumulating in fish if they eat other fish, and if they live long enough to build up those contaminants, said Roach.

For example, salmon aren’t monitored by the program because they simply die too young. “They’re too young to be dirty,” said Roach.

Most salmon don’t tend to live past seven, whereas lake trout can live up to 100 years, he added.

The program monitors trout in Lake Laberge and Kusawa Lake.

The only First Nations that rely on lake trout are the Teslin Tlingit Council and Kluane First Nation, otherwise it’s salmon or whitefish, said Roach.

Whitefish used to be monitored – all species in 38 lakes.

“But whitefish are so clean they squeak,” said Roach. The program has stopped testing them.

There are no plans to retest any species or plants in any number of years, said Gamberg, noting that levels in the Yukon are so low that it just doesn’t seem necessary.

The only time Yukoners have to worry about contaminant poisoning is if they eat something like 42 kidneys or livers a year, said Gamberg – a moderate diet of traditional foods is completely safe.

“It always depends on how much you eat,” she said. Five kilograms of caribou meat each day may be worrisome, she said.

There is also a concern for smokers when it comes to cadmium, which naturally exists in moose and caribou. The silver-white metal exists in zinc ore and is a byproduct of zinc smelting.

But those levels are not a risk, except for some heavy smokers, said Gamberg.

“And then it’s best to limit your intake of cigarettes, rather than moose,” she said.

However, if there is another disaster like Fukushima, or if things appear to be changing, the Porcupine caribou will let us know, she added.

There are plans to continue monitoring the caribou for many years to come and archival data on the herd continues to grow, making it an even better measurement, she said.

The years of data already collected show a mercury cycle in the caribou. The cycle has never reached risk levels, but scientists like Gamberg hope this information helps them figure out why it is happening, which can lead to a much better understanding of mercury in the entire environment.

Contact Roxanne Stasyszyn at

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

Kwanlin Dün First Nation chief Doris Bill holds up a signed copy of the KDFN <em>Lands Act</em> agreement during an announcement at the Kwanlin Dün Cultural Centre in Whitehorse on Oct. 20. Under the new act, called Nan kay sháwthän Däk’anúta ch’e (We all look after our land) in Southern Tutchone, KDFN will be able to allot citizens land to build their own houses on, for example, or to use for traditional activities. The First Nation will also be able to enforce laws around things like land access and littering. (Crystal Schick/Yukon News)
Kwanlin Dün First Nation’s Lands Act comes into force

The act gives the First Nation the authority to manage, protect and enforce laws on its settlement lands

Two doctors in Watson Lake say they are at risk of losing their housing due to a Yukon Housing Corporation policy that only allows one pet per family. (Wikimedia Commons)
Healthcare workers in Watson Lake say housing pet policy could force them to leave

The Yukon Housing Corporation has threatened evictions for having more than one pet

The Many Rivers Counselling and Support Services building in Whitehorse on March 28, 2019. Three people who sat on Many Rivers’ board immediately before it closed for good say they were relieved to hear that the Yukon RCMP has undertaken a forensic audit into the now-defunct NGO’s financial affairs. (Crystal Schick/Yukon News file)
Former Many Rivers board members relieved to hear about forensic audit, wonder what took so long

Three people who sat on Many Rivers’ board immediately before it closed… Continue reading

Whitehorse General Hospital in Whitehorse on Feb. 14, 2019. The Yukon Employees’ Union and Yukon Hospital Corporation are at odds over whether there’s a critical staffing shortage at the territory’s hospitals. (Crystal Schick/Yukon News file)
YEU, Yukon Hospital Corp. at odds over whether hospitals are understaffed

YEU says four nurses quit within 12 hours last week, a claim the YHC says is “inaccurate”

Two former Whitehorse Correctional Centre inmates, Ray Hartling and Mark Lange, have filed a class action against the jail, corrections officials and Yukon government on behalf of everyone who’s been placed in two restrictive units over the past six years. (Joel Krahn/Yukon News file)
Class action filed against Whitehorse Correctional Centre over use of segregation

Two former Whitehorse Correctional Centre inmates have filed a class action against… Continue reading

Smartphone showing various applications to social media services and Google. (Pixabay photo)
National media calling for level playing field with Google, Facebook

In Canada, Google and Facebook control 80 per cent of all online advertising revenues

Education Minister Tracy-Anne McPhee, right, before question period at the Yukon legislative assembly in Whitehorse on March 7, 2019. The Yukon government announced Oct. 19 it has increased the honoraria rates for school council members. (Crystal Schick/Yukon News file)
Honoraria increased for school council members

Members of school councils throughout the territory could soon receive an increased… Continue reading

Triple J’s Canna Space in Whitehorse on April 17, 2019, opens their first container of product. Two years after Canada legalized the sale of cannabis, Yukon leads the country in per capita legal sales. (Crystal Schick/Yukon News file)
Yukon leads Canadian cannabis sales two years after legalization

Private retailers still asking for changes that would allow online sales

A sign greets guests near the entrance of the Canada Games Centre in Whitehorse on June 11. The city announced Oct. 16 it was moving into the next part of its phased reopening plan with spectator seating areas open at a reduced capacity to allow for physical distancing. (Crystal Schick/Yukon News file)
CGC reopening continues

Limited spectator seating now available

During Whitehorse city council’s Oct. 19 meeting, planning manager Mélodie Simard brought forward a recommendation that a proposed Official Community Plan amendment move forward that would designate a 56.3 hectare piece of land in Whistle Bend, currently designated as green space, as urban residential use. (Courtesy City of Whitehorse)
More development in Whistle Bend contemplated

OCP change would be the first of several steps to develop future area

EDITORIAL: Don’t let the City of Whitehorse distract you

A little over two weeks after Whitehorse city council voted to give… Continue reading

Whitehorse City Hall. (Joel Krahn/Yukon News file)
City hall, briefly

A look at decisions made by Whitehorse city council this week

Northwestel has released the proposed prices for its unlimited plans. Unlimited internet in Whitehorse and Carcross could cost users between $160.95 and $249.95 per month depending on their choice of package. (Yukon News file)
Unlimited internet options outlined

Will require CRTC approval before Northwestel makes them available

Most Read