Researchers say they’ve found evidence of the first invasive barnacle species in Nunavut’s waters – a discovery they believe is a result of warming waters.
They published their findings last month in the journal Global Change Biology.
They explain the Arctic’s cold waters have – for the most part – prevented invasive species from migrating north. But with the Arctic warming up nearly four times faster than anywhere else on Earth, shipping routes are opening up, and the region’s waters are losing their thermal barrier against invasive species.
Shipping traffic in parts of Arctic Canada has increased by over 250 percent since 1990, according to the report, and that’s providing a vector for transporting non-Indigenous species to the region.
The bay barnacle (Amphibalanus improvisus), which is already present in European waters and the Pacific Ocean, was detected in ten different areas across Canada’s Arctic.
Betty Boyse, a molecular biologist with the British Antarctic Survey and co-author of the study, carried out the work while on cruise ships.
Most barnacles in that study were detected near Pond Inlet, which serves as a gateway into the Northwest Passage.
Researchers didn’t actually see the barnacles with their own eyes. Rather, they detected them using environmental DNA they collected from the waters they cruised through.
“Essentially all I have to do is go and collect a bucket of seawater, and within the seawater, I basically am collecting any shed skin cells, any poo, anything that organisms are putting into the environment … and I can use this to actually identify what species have been there,” she said.
As for why the researchers chose to gather data from a ship, she said barnacles are filter feeders which latch onto surfaces and suck their food through water.
“Boats are actually a really appealing place for them to stick onto because as the water flushes through, as the boats move, they get extra food from this,” she said.
Arctic becoming increasingly vulnerable
While Boyse doesn’t believe the bay barnacle alone will destroy the entire ecosystem, she said it’s a worrying first sign.
“I think what the barnacle really does signify is that this incredibly pristine environment is starting to become vulnerable to invasive species,” she said.
In written responses to CBC News, Fisheries and Oceans (DFO) Canada said it acknowledges the study’s important findings. While environmental DNA is a valuable monitoring tool, DFO said it’s not necessarily proof of a reproducing organism.
“Additional monitoring and visual confirmation is required to determine whether the detected environmental DNA corresponds to a live organism or whether it reflects transported genetic material,” DFO wrote in an email.
DFO said it uses a combination of environmental DNA techniques, scientific research and community-based monitoring programs with Indigenous communities to help track the introduction of aquatic invasive species in the Arctic.
Shelley Elverum helped start Ikaarvik, a non-profit organization based in Pond Inlet, which also worked on the study. She said it’s important for Canada to work with Inuit communities and empower them to set their own research priorities.
“Not just research coming in that has Inuit as boat drivers or camp cooks or bear guards, but understanding that Inuit have the most incredible depth of knowledge of what is normal and what is not normal.
Other invasive species heading north
DFO said other non-indigenous aquatic species have been detected in the Canadian Arctic. However, it’s not confirmed whether those are a result of human introduction, and DFO said those aren’t species which are banned and controlled under the Aquatic Invasive Species Regulations.
A different study co-authored by a Fisheries and Oceans (DFO) Canada scientist in 2015 found bay barnacles along the southern edge of Canada’s Arctic, near Churchill, Manitoba, due to hull fouling.
That report states Churchill’s port is – within the Canadian Arctic – at greatest risk of non-Indigenous species being introduced there because it receives the largest number of vessels and sees the largest amount of ballast water discharged.
The scientists who examined Nunavut’s waters also partnered with the Aqqiumavvik Society in Arviat, Nunavut, to study an area with little shipping activity.
Jimmy Qamaniq Muckpah, the society’s young hunters manager, said the waters near the community are quite shallow for ships. They found no barnacles in the area.
But in recent years, he’s seen other non-Indigenous animals like bats and wasps near Arviat, which is the southernmost community on Nunavut’s mainland.
“Some of [the invasive species] are probably going on the ships or some of them are running away from the smoke from the forest fires,” he said.
Stopping the spread
The risk of invasive species entering the Arctic will continue to grow as shipping routes open up, which is why Boyse urges the Canadian government to be proactive in protecting local communities.
That includes increasing monitoring and introducing regulations – which aren’t just voluntary guidelines – for vessels entering the region.
In written responses to CBC News, Transport Canada referenced several regulations the government of Canada has in place, which include pollution reporting obligations and ballast water management standards.
Canada also has guidelines for cleaning vessels and managing biofouling – which is when organisms build up on surfaces such as a vessel’s hulls – that Transport Canada said it has worked on with the International Maritime Organization.
“In April 2025, the International Maritime Organization also agreed to a proposal co-sponsored by Canada to start creating legally binding international measures for ship biofouling,” Transport Canada wrote in an email.
