For Alex Ootoowak, watching speckled gray narwhals glide through the icy Arctic during hunting season is a treasured childhood memory. Living in Mittimatalik (Pond Inlet) in Canada’s far north, he recalls whales streaming by all day in what felt like a continuous loop. Hunters in his community are taught to be very quiet and careful because narwhals are so sensitive.
More than 80,000 narwhals live mainly in northeastern Canada and Greenland. For Inuit communities around Mittimatalik, narwhal meat has been a staple for at least a thousand years, providing protein, iron and vitamin C, and hunting is regulated by authorities. “This is our means of staying healthy and connected to the land and our culture,” Ootoowak said.
But those dense migrations have thinned. Over two decades hunters noticed whales getting skinnier and harder to catch. By 2021, local counts fell to about 2,000—a roughly 90% drop from over 20,000 in the early 2000s. The reasons are not fully understood. Scientists point to climate change — the Arctic is warming much faster than the global average — affecting ice, water temperatures and food webs. Yet researchers note the population decline happened quickly, and one fast change in the area was a sharp rise in ship traffic.
A port opened in 2015 for a nearby mine run by Baffinland. Within two years, around 4 million tons of iron ore were being shipped through waters off Mittimatalik, and underwater noise rose substantially. Concerned residents and scientists set up acoustic monitoring to see what the extra sound did to marine life.
Ootoowak and Kristin Westdal of Oceans North began with two listening stations in Milne Inlet and later expanded the project with acoustics experts at the Scripps Institution of Oceanography. They lowered hydrophones through ice and down roughly 800 meters to listen around the clock. The recordings captured marine vocalizations — seals, foraging narwhals — and the rumble of ship engines. The team published a study in 2025 showing that narwhals either move away or stop calling when vessels come within about 20 to 40 kilometers (12–24 miles). The whales reacted to noise levels below 120 decibels, a disturbance threshold typically associated with mid-sized whales.
Hunters report similar behavior changes. Ootoowak said when ships rev engines, narwhals move off, stop feeding and avoid deep foraging dives. Over time the whales have learned to avoid heavily used shipping channels when boats are present.
Where the displaced narwhals go is unclear. Ootoowak visited northern Greenland in 2024 and heard from hunters there that unfamiliar, longer, skinnier narwhals had started appearing around the same time shipping increased near Mittimatalik. Those Greenland hunters said the newcomers tasted different and were easier to catch. Outi Tervo, a senior scientist at the Greenland Institute of Natural Resources, studies narwhals and noise impacts and has observed that shipping and exploration noise can make narwhals stop foraging, which could explain poorer body condition. Tervo has not found definitive evidence that Canadian narwhals relocated en masse to Greenland but said changing soundscapes might push animals to shift distribution.
Narwhals rely on echolocation to find prey and navigate; hearing is as vital to them as sight is to humans. Sounds that mask or disrupt echolocation can leave narwhals “ready to escape” and unable to feed effectively. Their habitat options are limited — they are adapted to Arctic conditions and cannot simply relocate to distant, warmer seas. Tervo emphasizes creating safe havens and considering the species’ needs in management decisions.
The monitoring effort has helped raise awareness. Baffinland has adopted mitigation measures: reducing ship speeds to about 9 knots, using fixed routes and agreeing to stricter rules for icebreaker use. Some cruise operators have agreed to speed limits and no-go zones. Those changes, plus continued engagement between industry, governments and Inuit communities, appear to be yielding early benefits: the 2025 fall hunt produced better results than in recent years, Ootoowak said.
Scientists warn that as sea ice retreats, maritime traffic through routes like the Northwest Passage is likely to grow, bringing more cruise ships, pleasure vessels and commercial traffic. Westdal says stronger oversight, collaboration with local communities and more data are essential to manage noise pollution before it causes further harm. Policies and regulations tailored to the Arctic’s unique environment will be important to protect narwhals and other species as the region opens up.