A line of pink lingers above the horizon, the April sun offering a welcome dose of brightness after the months-long polar night. A dozen miles off Point Barrow, Alaska’s northernmost tip, the sea is still frozen except where inky tendrils of open water spiderweb across the pack ice. On the surface, the scene feels hushed by the cold. But if you were to dip a hydrophone beneath the ice — like biologist Kate Stafford did this past spring — you might be surprised by what you hear.
Sounds from the spring bowhead whale migration, heard from the sea ice edge at Utqiagvik, Alaska. The downsweeping trills in the background are from male bearded seals. Recording provided by Kate Stafford/Oregon State University
Underwater, a carnival of sound is unfolding, with bowhead whales the featured act. Somewhere, a mother calls to her newborn calf, guiding her young along a route she’s navigated dozens of times before. Several males compete for the season’s final serenade, singing, as bowheads do, with two voices at once. There’s a growl, a “gunshot,” a burp, a series of upsweeps and downsweeps — the phonemics of a language only these whales can understand.
Scientists like Stafford, a professor at Oregon State University, are eavesdropping on the action. With a toolkit of recording techniques, they’re tracking a dramatic story of change.
The underwater acoustic landscape defines the life of Balaena mysticetus, the bowhead whale. Imagine swimming in frigid, pitch-black waters beneath the ice of a frozen sea, using echolocation as your guide. Alaska’s bowheads migrate in the near-complete darkness of late winter and spring, traveling from their winter range in the Bering Sea to spend summer in the eastern Beaufort Sea, more than 1,500 miles away. To avoid becoming trapped in the ice, they negotiate this complex environment through sound, honing skills developed over more than 10,000 years in the Arctic.
For bowheads — Aġviq in Iñupiaq — sound is essential, not only for navigating but for finding food, connecting with mates, and even breathing. To surface, the whales must detect patches of open water or areas of thin ice, which they can break through — at thicknesses up to two feet — using their powerful heads. They listen for predators and home in on prey while mapping the subtle contours of the seafloor. Given bowheads’ reliance on sound, it’s no coincidence that these long-enduring, soniferous animals also sing some of the most complex and innovative songs on the planet.
Now, however, they face a new threat: Arctic waters are getting noisier, and fast.
For bowheads, sound is essential, not only for navigating but for finding food, connecting with mates, and even breathing.
BOWHEADS ARE THE only whales that live year-round in the Arctic. The ones that inhabit the waters around Alaska and northwestern Canada were spared from the slaughter of industrial whaling until the mid-19th century, several hundred years later than in other parts of their range. They now comprise the only stable — and perhaps growing— bowhead population, currently estimated at 12,000 to 14,000 individuals, and they remain an important subsistence resource for Alaska Native communities.
A bowhead can live to be well over 100 and, according to some estimates, as much as 200 years old. The species’ impressive lifespan has long been acknowledged among Indigenous residents and more recently confirmed by dating bone and ivory fragments from hunter-harvested whales and performing chemical analyses of whale eye lenses and reproductive organs. In theory, a bowhead living today could have witnessed the earliest commercial whaling ships sail into Alaska’s waters, lived through the latter part of the Industrial Revolution and heard the first oil drill boring into the Beaufort Sea.
Only later did biologists begin to listen in on their lives. Sonobuoys deployed from an aircraft in the late 1970s offered the first formal documentation of bowhead calls and songs. The resulting scientific report, published in the Journal of the Acoustical Society of America in 1982, marked just the latest technological advance in a longstanding field of study. In 1979, Christopher Clark, who conducted some of the earliest acoustic surveys in Arctic Alaska, noted that his Iñupiat colleague Benny Nageaq knew all the species at Point Barrow by voice. “(Nageaq) patiently explained how his ancestors had listened, too, not with a hydrophone, but with an oar paddle placed into the water with the butt of its handle against the jawbone.”
Even today, Arctic underwater soundscapes are, at a baseline, quieter than their temperate or tropical equivalents, not only because there are fewer sources of anthropogenic noise, but because ice acts as a powerful dampening force. It scatters sound waves that hit its underside, modulating the intensity and distance they can travel. Ice also limits vessel traffic, but as it recedes earlier and faster each season, open water routes are becoming more accessible.
Median noise levels will nearly quadruple across the pan-Arctic by 2030, relative to levels measured in 2019, according to a report produced by the Protection of the Arctic Marine Environment and the Arctic Council earlier this year. Because sound is not uniformly distributed, the rate and scale of the changes vary. In places with low ambient noise, small increases in vessel traffic can have a disproportionate effect. In the Chukchi Sea, for example, where Alaska’s bowheads spend part of their year, natural sounds like whales, walruses and wind currently have a greater impact on the soundscape than ship-driven noise. By 2030, however, that dynamic is expected to flip, with ship noise taking the largest share of the bandwidth.
Because bowheads’ home waters in Alaska and Canada are inaccessible much of the year, biologists’ ability to study these environments has also historically been limited. However, over the past four decades, improvements in acoustic technology and oceanographic monitoring, combined with a growing number of recording stations, have helped highlight the importance of sound in the underwater lives of Arctic animals.
Today, passive acoustic monitors help biologists estimate population sizes, track movements and identify feeding hotspots for bowhead whales and other marine mammals. These hardy devices return data in the form of spectrograms, colorful frequency charts showing patterns of scattered dots and vertical spikes. By reading what amounts to a series of Morse code patterns emerging from the seafloor, biologists can infer which species are in the area and what they might be doing.
Listening underwater also helps identify the potential impacts of noise pollution. A series of studies dating back to the 1980s augmented traditional ecological knowledge about bowheads’ sensitivity to vessel noise; it’s now well established that they will alter their course to avoid ships, or even aircraft. Airguns and other oil and gas activity can also affect whale dive cycles and vocalizations. During seismic surveys in the Beaufort Sea in 2007-2010, for example, Susanna Blackwell and her colleagues found that bowheads increased their calling rates in response to low decibel sounds, but at high noise levels they stopped communicating altogether. Marine mammals aren’t alone in feeling the effects of noise; many fishes and zooplankton are also sensitive to sound and, at acute decibel levels, can be injured or killed.
Even if decibel levels remain below directly harmful thresholds, increasing ambient noise can affect animals’ ability to communicate. Bowheads’ vocalizations, and their ability to perceive sound, may be drowned out by a phenomenon known as “acoustic masking” — the undersea equivalent of trying to hold a conversation in a windstorm. This sort of background interference with bowheads’ daily activities ranks among Stafford’s greatest concerns.
AS THE ARTIC HEATS UP, so too do sources of industrial noise pollution. Offshore oil and gas production has been underway in Arctic Alaska since the 1970s. However, the stakes of such development have recently risen with the implementation of several presidential executive orders. President Donald Trump’s January 2025 order “Unleashing Alaska’s Extraordinary Resource Potential” promised to unlock “this bounty of natural wealth.” What the fine print of this sweeping order doesn’t reveal is the potential collateral damage from increased offshore development, including its impact on some of the Arctic’s quietest soundscapes.
Warmer oceans have also spurred commercially valuable fish such as cod and pollock to move north, attracting new fishing fleets to the northern Bering and Chukchi seas. Another executive order calls for the rollback of fishing regulations and catch limits in U.S. waters. Meanwhile, political jockeying for potentially valuable shipping routes and greater militarization of this region will presumably draw even more traffic.
Anthropogenic sources of noise aren’t the only climate-related changes to bowhead soundscapes. As sea ice disappears, the ocean has greater fetch, allowing the buildup of waves. The same storms that hit land also make a ruckus underwater. Breaking surf, crashing ice floes and wind gusting across the water’s surface mean more ambient noise across all frequencies for bowheads to contend with. As Stafford explained, “Imagine a radio station that can’t be tuned in properly; you can hear that there’s music playing, but the static makes it hard to tell what is being played.”
A bowhead whale recorded in the Chukchi Sea. The animal sang for hours and hours almost non-stop under the ice during polar night. Recordings provided by Kate Stafford/Oregon State University
Longer periods of open water in the Arctic also mean that new neighbors are moving in. Alongside the region’s usual underwater chorus — trilling bearded seals, knocking walruses, grunting Arctic cod and crunching krill — unfamiliar voices have begun to emerge. Over the past several years, acoustic monitoring has revealed the growing presence of orcas and humpback whales in the Pacific Arctic during summer and fall. In a study published in Polar Biology earlier this year, researchers from the University of Washington and the National Oceanic and Atmospheric Administration (NOAA) determined that orcas are not only becoming more common in the region, they’re arriving more than a month earlier each year as the sea ice decreases.
For bowheads, these novel clicks and whistles signal trouble. A pair of studies published in Polar Biology in 2020 and 2022 documented 25 bowhead whales that were presumably killed by orcas during 2009-2019, with a notable spike in the western Beaufort Sea in 2019. This corroborated the evidence of subsistence hunters, who had harvested whales with scars indicative of orca attacks. In the presence of orcas, bowheads, especially mothers traveling with calves, may silence their calls to avoid predation.
Humpback whales are not a direct threat to bowheads, but their vocalizations overlap with bowhead frequencies, meaning there could be competition between the species for acoustic “space” and perhaps other resources. According to Stafford, who has been studying whales in the Arctic for two decades, bowheads are increasingly likely to feel the crunch as humpbacks move north. Her first sighting of a humpback in the Beaufort Sea was in 2021; she’s since dubbed the summer of 2024 a “humpbackpalooza,” with large numbers of humpback whales sighted in an area also heavily frequented by migrating bowheads.
The changes are happening faster than scientists can track them. Both sea ice melt and Arctic shipping have already exceeded most model predictions; the Arctic Council’s 2025 report, for instance, notes that its own previous projections for 2030 noise levels may have underestimated vessel traffic by as much as 40%. These models also assumed a pre-Trump regulatory framework and anticipated oil and natural gas leases. In other words, they didn’t factor in an aggressive push for offshore drilling and fishing or the potential reversal of major U.S. environmental regulations. Given the increase in commercial activity that the current administration is pursuing, acoustic impacts on bowheads and other species may be much more severe than the hypothetical accelerated scenarios.
At the same time, basic research on Arctic soundscapes is threatened. Many of the programs critical for deploying and maintaining acoustic monitors, including those overseen by NOAA, are at immediate risk of defunding. Decades of monitoring could screech to a halt, leaving some of the most urgent questions unanswered.
Even as funding from U.S. sources dries up, the Arctic Council, the Protection of the Arctic Marine Environment and other international working groups have emphasized the urgent need to develop real-time mitigation strategies in the region. Vessel speed limits, rerouting of ships and the establishment of “sound reserves” are among some of the measures proposed. Stafford also cites the need for better acoustic mapping in order to identify highly sensitive areas. Above all, increased collaboration between stakeholders — scientists, industry leaders, local communities and Indigenous-led groups such as the Alaska Eskimo Whaling Commission — will be essential to protect these rapidly changing acoustic habitats.
Median noise levels will nearly quadruple across the pan-Arctic by 2030, relative to levels measured in 2019.
IN SEPTEMBER, bowheads return to the waters around Point Barrow. This time, they aren’t dodging ice but gulping enormous mouthfuls of zooplankton, which are so dense they can be seen on satellite images as a brownish-pink smear across the water. Here, at the margin of the Chukchi and western Beaufort seas, a unique combination of bathymetry and winds coalesce each autumn to create what is known as a “krill trap.” For bowheads, this translates into a feast of whale-sized proportions.
Since its initial discovery via aerial surveys, biologists have been listening in on this fall feeding frenzy. Hannah Sawyer, a recent graduate student in Stafford’s lab, determined that when the krill trap is “on,” bowhead call rates increase in frequency by as much as 20 times; the whales also make more complex vocalizations that could signal cooperative feeding. No one knows exactly how bowheads detect this ephemeral food source, but sound likely plays a role. The krill trap is so critical for their late-season fattening that they will tolerate higher decibel levels from vessels and other sources just to keep feeding.
The question is how much noise is too much, and whether we humans can quiet our own activities enough to allow bowheads the acoustic space they need. For the bowheads, as for all of us, the ending is yet unsung.
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This article appeared in the October 2025 print edition of the magazine with the headline “Eavesdropping on the Arctic.”
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