PRINCE CHARLES ISLAND
When Paul Smith, a researcher with Environment and Climate Change Canada, flew over Prince Charles Island last month, he was looking for a new site to study birds.

Paul Smith discovered 47 caribou carcasses on Prince Charles Island last month. "I've not seen so many dead caribou in one location before," he said. - photo courtesy of Paul Smith

He wasn't expecting to stumble upon almost 50 dead caribou.

"We noticed these strange looking shapes and as we landed we realized they were the carcasses of caribou," said Smith, who is an adjunct research professor at Carleton University. "And because I'm familiar with conservation issues in Nunavut in general I realized it was maybe an important find in light of the status of the Baffin caribou herd."

In 2015 the Government of Nunavut imposed the first-ever Baffin Island caribou quota, of just 250 animals per year, in response to the discovery that caribou numbers in the region had plummeted.

An aerial survey by the territorial government the year before found that the caribou population had declined 90 to 95 per cent since the 1990s, going to between 3,462 and 6,250 from around 120,000 to 330,000 animals About a third of the herd today lives on Prince Charles Island, located off the west coast of Baffin Island.

The Department of Environment stated in an e-mail that 47 caribou carcasses were found on Prince Charles Island.

"What was interesting was that they were all in one location, so you had the impression that all of these caribou of different sizes and ages had died at the same time," said Smith. He says the carcasses he found were clustered along the sides of eskers, narrow gravel ridges.

"So these areas have a lot of the food that caribou prefer and they also act as wind and snow breaks. The carcasses were concentrated along either side of these ridges, so that gives the impression that possibly the caribou had sought out these areas, either because there was less snow or there was more food or there was something that made this area more attractive to them at the time that they died," he said.

Although he says the exact time frame for the die-off is unknown, he said that it was probably between early winter and late spring, because some of the carcasses were buried in snow.

The cause is still unknown, although Smith has his own suspicions. He initially wondered if this could be brucellosis, a bacterial disease that impacted caribou herds in the region in the past, particularly on Southampton Island.

"But in a disease die off you wouldn't expect young, old, male, female to all die in the same location. It just wouldn't look like that. So that seems unlikely to me," he said. "I've not seen so many dead caribou in one location before, that's why I was struck by it."

Scenario is not without preceden

He doesn't think the caribou necessarily starved, because he says there was plenty of lichen on the island.

"There was lots of lichen on the island. The question is whether or not they could get it. If I were to guess, it would seem to me that a plausible scenario would be that some kind of late spring weather event prevented them from accessing their food," said Smith. "They couldn't dig down to the lichens because of a freezing rain event, possibly, or something like that. We need to look and see whether or not there were sufficiently nasty weather events that could explain that."

He says such a scenario is not without precedent. "Is it uncommon? Maybe it's not a regular occurrence to have a die-off event like this but it's certainly not unheard of, it has happened in the past," Smith said. "But that being said, one of the weather events that's particularly hard on them is when rain falls on snow and it freezes, and these are predicted to be more frequent with climate change.

"This is one of the concerns that caribou biologists have looking forward about the effects of climate change, that this increasing frequency of rain on snow events is going to negatively effect the caribou."

The Department of Environment is continuing to investigate, submitting samples last week taken from the carcasses to try and determine the cause of death.

"Since the investigations into the cause and extent of the die-off and health of the deceased caribou are still ongoing, we feel it wouldn't be appropriate to comment further at this time," the department stated in an e-mail to Nunavut News/North.

"It's a concern but, the question is, is this a more widespread phenomenon -- that hasn't been established yet," said Smith.

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