Declining muskrats in the delta: Low water levels and otters may be a cause, biologist says

A biologist researching muskrats in the Mackenzie Delta says there's been a decline in muskrat populations in the area for over a decade, and locals want answers.

It's been 15 years since he first started noticing the steep muskrat decline, says local trapper

Dougie Joe from Inuvik trapping muskrat in March of this year. Joe says it's been 15 years since he first started seeing a 'steep decline' in muskrats, without the population rebounding. (submitted by Chanda Brietzke)

When Dougie Joe of Inuvik, N.W.T., was growing up, his aunts, uncles and mother always told him to watch carefully as he cleaned out his hunted muskrats.

"Like watch for pus on the liver, and there may be tumours in the stomachs or the guts. To watch for when they're going to start decline in numbers," said Joe.

Today, Joe says that it's been 15 years since he first started seeing a "steep decline" in muskrats, without the population rebounding.

"The main thing we've been hearing over and over for several years now is that the muskrats are really depleted," said Chanda Brietzke, a biologist from the University of Victoria researching muskrats in the territory's Mackenzie Delta region. 

Since 2013, she's made several trips to the delta to conduct aerial and ground surveys, live trapping and collecting muskrat carcasses for examination.

Chanda Brietzke, a biologist from the University of Victoria, interviews local trappers like Neil Snowshoe, a Gwich'in Elder from Fort McPherson. (submitted by Chanda Brietzke)

Brietzke's interviews with local trappers have revealed a perplexing situation that's leaving even longtime trappers confused.

"They've declined, and we don't know why they're declining. Something is happening," said Danny C. Gordon of Aklavik to Brietzke.

"The last number of years, it's disappeared. Like you know. Just gone, like. I don't see muskrat, there's nothing," Fred Koe, a Gwich'in trapper from Fort McPherson, told Brietzke.

Why it matters

"It matters to people because muskrats have been and continue to be an important part of living that lifestyle out on the land, and they're an important food for many people," said Brietzke.

Joe is a traditional knowledge advisor to Brietzke. They trapped muskrats together in March of this year. (submitted by Chanda Brietzke)

"I'm a trapper. I grew up in a bush, and frankly I just love being out there," said Joe who works with Brietzke as a traditional knowledge advisor, guiding her to locations where muskrats are usually found.

"That's what I grew up doing, so [it's] kind of a really important fur-bearing animal to me."

"People love muskrat. I love muskrat," said Brietzke. "They wish they could be harvesting more, they wish they could be on the land, but the muskrats aren't there."

Theories from otters to low water levels

Environmental change is one theory.

"A lot of those lakes where my dad used to trap, I go to them nowadays, a lot of them are still good but other ones are totally drained out," said Joe.

Brietzke said water levels in many lakes are declining, which may affect the population.

She also said that other animal populations have increased, such as beavers and otters.

Brietzke is collecting and examining muskrat carcasses for answers. (submitted by Chanda Brietzke)

"As far as otters go, they're really, really voracious predators of the muskrat. So as their populations increase, we'd expect that they are probably taking out a lot of muskrat," she said.

Brietzke said it's still too early for any concrete answers, though she hopes to present some results from her research in January. 

"We still haven't answered the question of 'What's going on?'… so we're just continuing to kind of get at that from as many angles as we can."

with files from Joanne Stassen


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