For Alex Ootoowak, who grew up in Mittimatalik (Pond Inlet), the sight of speckled gray narwhals sliding through nearby waters during hunting season is a cherished memory. He recalls long, looping processions of animals and the care taught to hunters — “extra, extra quiet” — because narwhals are so sensitive to disturbance.
More than 80,000 narwhals live mainly around northeastern Canada and Greenland, and for Inuit communities like Mittimatalik’s, narwhal meat has been a vital food source for generations, supplying protein, iron and vitamin C. Hunting is regulated and remains an important cultural practice and means of connection to the land.
But the migrations Ootoowak remembers are increasingly rare. Over the last 20 years hunters in the region have reported fewer catches and leaner whales. By 2021 local counts suggested only about 2,000 narwhals remained near Mittimatalik — roughly a 90% decline from more than 20,000 in the early 2000s.
Researchers point to several possible drivers, including climate change, which is altering sea ice, water temperatures and food webs in the Arctic. Yet marine mammal specialists say one of the most abrupt local changes has been the surge in vessel traffic. Kristin Westdal of Oceans North noted that while many Arctic changes are gradual, the number and volume of ships increased quickly once a nearby port opened.
In 2015 Baffinland opened a port close to Mittimatalik to ship iron ore. Within two years millions of tons of ore had passed through local waters and underwater noise rose sharply. Alarmed by the new acoustic footprint, Ootoowak and Westdal installed listening stations in Milne Inlet and later teamed with acousticians at Scripps Institution of Oceanography to expand monitoring.
Using hydrophones deployed through the ice to depths around 800 meters, the researchers recorded a continuous underwater soundscape — from seals and narwhal clicks to the low-frequency rumble of ship engines. Their 2025 analysis found that when vessels came within roughly 20 to 40 kilometers (12 to 24 miles), narwhals either moved away or fell silent. The whales reacted to sound levels below about 120 decibels, a level known to disturb mid-sized whales and comparable to a loud thunderclap.
Hunters in Mittimatalik reported similar changes at the surface. Ootoowak described narwhals stopping feeding and abandoning deep foraging dives when ships started up, and avoiding busy channels. Over time such disruptions could reduce feeding success and body condition, consistent with observations of leaner animals.
Some hunters say the whales may be shifting east toward Greenland. During a 2024 visit to northern Greenland, Ootoowak heard accounts of “foreign” narwhals — longer, skinnier whales with different behavior and taste — showing up as shipping increased off Mittimatalik. Outi Tervo of the Greenland Institute of Natural Resources has documented how noise from shipping and oil and gas activity can interrupt narwhal foraging. While she has not found definitive proof of a mass relocation, she agrees that rising or unfamiliar noise can change migration and habitat use.
Narwhals depend on echolocation to find prey and navigate in dark, icy waters. Tervo likens their hearing to human sight: sounds that mask echolocation can be as disabling as a flashlight in your eyes and can trigger escape behavior. Given the narwhal’s narrow habitat needs, she emphasizes protecting quiet refuges.
The monitoring work also spurred management changes. Baffinland has reduced transit speeds to about nine knots, set fixed shipping routes and agreed to tighter rules for icebreaker use. Cruise operators have accepted speed limits and no-go zones. These measures appear to have helped: community members reported that the 2025 fall hunt was the first in a decade that produced satisfactory harvests.
Westdal stresses that stronger oversight, collaboration with local communities and expanded acoustic monitoring will be essential as Arctic waters open and interest in trans-Arctic shipping grows. Policies tailored to Arctic conditions will be important for anticipating and managing future impacts on narwhals and the communities that rely on them.
This article is based on an episode of Living Planet produced by Kathleen Schuster. Edited by Sarah Steffen.