Using AI to protect caribou migration in a changing Arctic

National Observer

11-06-2025

A machine learning tool is offering new hope for one of Canada's most vulnerable caribou migrations.
Researchers are turning to artificial intelligence to predict when and where the Dolphin and Union caribou will cross the sea ice between Victoria Island and the mainland of Nunavut — a migration that takes place each spring and fall but has become more dangerous as climate change thins the ice and shipping traffic climbs.
Caribou can drown if they try to cross ice that is unstable, and the risk increases when icebreakers and other vessels move through the area — and the ships are arriving in greater numbers than ever before. The tool called IceNet can help protect caribou by warning when migration conditions may be dangerous.
'Climate change is causing Arctic sea ice to recede and become less stable — which also means the region is becoming more accessible for ships,' said Ellen Bowler, a machine learning research scientist at the British Antarctic Survey who worked to develop the tool in partnership with the Alan Turing Institute, the World Wildlife Fund and Nunavut government. 'This combination of threats could have fatal consequences for iconic animals like caribou.'
Saving a vanishing herd
The Dolphin and Union caribou herd once numbered around 100,000 but dropped sharply in the early 1900s. The population grew again later in the century, but that recovery did not last. By 1997, there were about 34,000 caribou, and by 2020, only around 3,800 remained. When numbers dropped very low in the past, the migration even stopped for a time.
Elders and local hunters have reported even sharper declines, more sick and skinny animals, and fewer calves surviving. In 2017, the herd was officially listed as endangered, with experts warning of 'imminent extinction' if these threats continue.
'Instead of just forecasting sea ice concentration, we can actually start to forecast when they're most likely to migrate in a given year,' Ellen Bowler, a machine learning research scientist at the British Antarctic Survey.
Now, by analyzing decades of data collected by government agencies, Inuit hunters and community researchers, the new AI system can predict the start of caribou migration up to three weeks in advance — giving vessel operators time to adjust their routes or pause shipping during this critical migration period.
'Instead of just forecasting sea ice concentration, we can actually start to forecast when they're most likely to migrate in a given year,' Bowler said.
Brandon Laforest, lead specialist for Arctic conservation at WWF Canada, works directly with Inuit communities on conservation priorities in Nunavut. He said that the technology offers a promising solution to a well-documented problem.
Inuit hunters and elders have seen caribou hesitate at the ice edge, fall through or abandon their usual crossing spots. Some animals try to cross where an icebreaker has left open water or broken ice, but get exhausted, drown or freeze if they can't climb back onto the ice.
'It gives caribou a fighting chance to continue their migration,' Laforest said.
Bowler said their team was initially searching for case studies where their Arctic-wide sea ice forecasting tool could have real, local impact.
'The Dolphin and Union caribou stood out because their migration is so closely tied to sea ice, and because icebreaking vessels are directly disrupting their routes,' Bowler said.
She said the system is designed to supplement local knowledge in Nunavut, not replace it.
'You hear in other AI stories, 'It's going to take everyone's jobs,' or like 'It's to replace humans.' It's definitely not about that. It's like providing information that people might not currently have or that isn't really accurate enough currently to act on properly,' she said.
Early warnings for a changing Arctic
Most North American caribou never cross sea ice, but the Dolphin and Union herd, collectively known to locals as Island caribou, cross twice a year — heading to the mainland of Nunavut and the Northwest Territories for winter and returning to the island for summer. The only other caribou known to do it are the much smaller Peary caribou.
'This is one very specific group of caribou, the Dolphin and Union herd, who very predictably go to the northern edge of the mainland of Canada, cross the sea ice to Victoria Island, spend their time there, give birth to their young, and then migrate back. It's an integral part of the biology of that herd, and it's pretty unique,' Laforest said.
As the Arctic warms, the ice is becoming thinner, which has led to an increase in shipping traffic in migration corridors like Queen Maud Gulf, Dease Strait, and Dolphin and Union Strait.
Icebreakers can also slow down the formation of new ice, leaving open water where caribou need to cross.
The risks are not limited to wildlife. The same stretches of sea ice are used by residents travelling between communities, often by snow machine, making unpredictable or broken ice a danger for people, as well.
Protecting more than a species
Laforest said the connection between wildlife and community well-being is especially strong in the Arctic, where caribou are central to the lives of Inuit and Inuvialuit communities for food security and cultural identity. They are working hard to protect caribou habitat while balancing environmental concerns with economic development.
'It's not only for food security reasons, but also for cultural continuity,' Laforest said.
The latest draft of the Nunavut Land Use Plan proposes restrictions on icebreaking through sea ice used by Island caribou for migration, but the plan is still under review and not yet in effect.
Learning as we go
The IceNet project is described by researchers as a first attempt to see if technology can help solve a conservation crisis identified by northern communities. Researchers say the approach is collaborative, combining AI forecasting with local expertise.
'It's meant to contribute to holistic, more locally led processes to create solutions that work with people and the wildlife of that region. It's very admittedly, sterile work from a long ways away, but it's trying to use data to address a problem that community members have identified,' Laforest said.
'But in no way is anyone saying this is the only solution. It's more of trying to stay on the edge of technology and trying to apply that technology to address concerns raised by communities as it relates to wildlife.'
Lapointe, a trained polar bear biologist who now describes himself as a generalist, said that if they can improve the tool's predictability, they hope to apply the tool to other species, including polar bears at the southern edge of their range.
For polar bears, the tool could predict their arrival on land near communities, providing early warnings and helping to mitigate human-polar bear conflict, said Bowler.
The technology could also track whale migration corridors to reduce shipping risks and monitor walrus haul-outs, which become vulnerable as sea ice disappears.
Researchers say that IceNet is still in its early stage, with ongoing improvements expected as on-the-ground observations and local knowledge are added.
'It's not about coming in with all the answers. The project is about working with local experts, using their data, and seeing if this technology can make a difference.' Bowler said.
'It's a pilot, and we're learning as we go.'