Whales at 70 north: East Greenland's food web is being rebuilt in one career's span

Researchers in Greenland, Denmark and Iceland report that fin, humpback and common minke whales are now feeding regularly along the East Greenland coast as far north as 70 degrees N, forming mixed aggregations in a region where all three were historically rare ^[1][2][3]. The relevant number is not the whales but their appetite: during a roughly four-month stay the animals may consume about 1.1 million tons of prey, an amount the authors say could reshape the regional food web ^[16].

That works out to on the order of 9,000 tons of fish and krill a day ^[17]. It is being removed from a system that, until recently, was not part of the temperate North Atlantic feeding circuit at all.

The evidence base is unusually broad for a wildlife claim. The team flew the first systematic aircraft surveys up to 50 km offshore in August 2015 and 2024, added airborne observations from summer 2022, testimony from Inuit hunters collected between 2023 and 2025, ship records from North Atlantic Sighting Surveys going back to 1987, and tracks from 15 satellite-tagged whales between 2019 and 2025, then modelled the records against sea surface temperature, salinity and ice concentration ^[4]. Sightings rose as water warmed and summer ice retreated ^[20].

The ship-survey series is the clearest signal. No humpback was recorded in the area until 2006; there were seven in 2007, 26 in 2015 and more than 150 in 2024 ^[6], a more than twentyfold increase across 17 years ^[30]. Minke encounters were few until 1995 and then ran at 10 to 20 a year after 2001 ^[7]; fin whale sightings rose sharply across the same period ^[8]. In August 2025 a ship crew reported up to 50 baleen whales together near 69 degrees N ^[9], and the 2015 and 2024 flights found an almost continuous distribution of all three species between 60 and 70 degrees N ^[10].

The mechanism is prey, not temperature preference. Capelin shifted their summer feeding grounds from north of Iceland toward the Greenland Sea after the mid-2000s, and the whales followed ^[14]; capelin were identified in minke stomachs from the region, while fin whales and humpbacks likely take both capelin and krill ^[15]. Because all three species avoid ice-covered waters, the post-2000 retreat of coastal pack ice opened the habitat ^[22][23].

Two numbers deserve caution. The abundance estimate for summer 2024 is reported as 4,000 humpbacks and 6,000 fin whales in both accounts, but 6,000 minke whales in one and 4,500 in the other, a 1,500-animal spread on a 14,500 to 16,000 total ^[11][12][13]. The warming figure also varies: roughly 2 degrees C since the 1990s in one telling, roughly 1 degree C after the late 1990s in the other, a factor-of-two difference in the headline driver ^[19][20][21].

There is no commercial capelin fishery in the region, so the authors see no immediate competition with human harvest ^[18]. That is the current state, not a guarantee. Heide-Jørgensen, who has worked in Greenland for 45 years and said he was surprised by the change ^[27], describes a major ecological regime shift in which narwhals increasingly share habitat with, or are displaced by, temperate baleen whales ^[24]; the team calls the process borealization ^[25]. He expects the system to become "more Atlantic than Arctic in function and species occurrence", and notes tuna already turning up as bycatch in East Greenland mackerel fisheries ^[26]. He also declines the easy framing, saying that had the ice held, the whales might simply have fed elsewhere in the North Atlantic ^[28].