For most of the twentieth century, fin, humpback and common minke whales were unusual sightings along the coast of East Greenland. A study published in Frontiers in Marine Science on 20 August 2026 estimates that about 16,000 of them were there in the summer of 2024, distributed almost continuously between 60°N and 70°N and within roughly 50 kilometres of the coast. The work is led by Mads Peter Heide-Jørgensen of the Greenland Institute of Natural Resources, with colleagues in Greenland, Denmark and Iceland.

The number is large enough to be worth stating carefully. It is an estimate of how many animals used a stretch of coast in one summer, not a count of a population, and the paper is about distribution rather than about how many fin or humpback whales exist in the North Atlantic. What has changed is where they are.

What the estimate rests on

The 2024 figure breaks down as roughly 4,000 humpback whales, 6,000 fin whales and 6,000 common minke whales, reported in the paper with 95 per cent confidence intervals. It comes from the first systematic aerial surveys of baleen whales flown up to 50 kilometres off the East Greenland coast, in August 2015 and again in 2024.

The longer trend comes from the ship records. Survey vessels did not report a humpback whale in this area until 2006. Seven were recorded in 2007, 26 by 2015, and more than 150 by 2024. Minke whale sightings were few until 1995 and then settled at 10 to 20 a year after 2001. Fin whale sightings rose steadily across the whole period.

Sighting counts are not abundance, and a rising count can reflect where and how hard people looked. What makes the pattern harder to explain away is that the two aerial surveys, nine years apart and designed for the purpose, independently found all three species spread along the same coast, and that in August 2025 a ship crew reported aggregations of up to 50 animals at around 69°N, well north of the Arctic Circle. Four separate kinds of evidence, gathered by different methods over different periods, point the same way.

A fish moved first

Two physical changes sit underneath the whale numbers. Sea surface temperatures east of Greenland have risen by approximately 2°C since the 1990s. The summer sea ice edge in the Greenland Sea has retreated steadily northwards, sharply after the mid-2000s, reducing the pack ice that once lined the east coast through the season.

The biological link the authors identify is capelin. The fish shifted its feeding grounds from the comparatively warm water north of Iceland towards the Greenland Sea from the mid-2000s. Capelin is already among the most important prey for all three whale species further south, and the paper concludes that the whales are in coastal East Greenland primarily to feed on it. No commercial capelin fishery has operated in this region, so there is no direct competition with a fleet at present. That is a description of the current situation, not a forecast about it.

What arrives, and what is already leaving

East Greenland is undergoing a major ecological regime shift.

Mads Peter Heide-Jørgensen, Greenland Institute of Natural Resources

Fin, humpback and minke whales are temperate animals that generally avoid ice-covered water. Their presence this far north is a consequence of the ice not being there. The authors describe ice-associated species, narwhal among them, as increasingly sharing habitat with the newcomers or being displaced by them, and frame the whole picture as a climate-driven reorganisation of the East Greenland marine ecosystem.

Readers of our conservation traveller’s guide to Greenland will recognise both the institute and the second half of that sentence. Aerial surveys in the East Greenland management areas south of 72°N estimated 2,758 narwhal in 2008, 702 in 2016 and 365 in 2022, and the scientific committee of the North Atlantic Marine Mammal Commission has recommended for years that catches there be reduced to zero.

It would be easy, and wrong, to read those two sets of numbers as cause and effect. The new paper does not test whether baleen whales are affecting narwhal, and no mechanism connecting them has been established. What the two bodies of work share is a driver. The same loss of sea ice that opened the coast to temperate whales removed the habitat the narwhal depends on, and hunting pressure on a shrinking population is a separate problem running in parallel.

Why this matters beyond the count

Abundance is a satisfying number and a poor summary. Sixteen thousand large whales feeding at the surface along a coast that had almost none within living memory is a change in the structure of the ecosystem, and structural change of this kind tends to arrive with a set of second-order questions that nobody has answers to yet: what happens to the capelin at these consumption rates, what the resulting nutrient flows do to the fjords, and how the fisheries that Greenland actually depends on respond.

It also lands on a coast that is receiving more vessels, not fewer. The same NAMMCO working group that advised zero narwhal catch asked the government to regulate large vessel traffic along the East Greenland coast, cruise ships included. Whales in the water are one input to that question. So is what those vessels emit while they are alongside, which we looked at in ten days of air quality measurements in Ilulissat.

Some species will do well out of a warming Arctic. That is not the same as the Arctic doing well, and this paper is unusually clear about the difference.

The study is open access: Feeding frenzies of baleen whales along East Greenland, Frontiers in Marine Science, 20 August 2026. Also in this issue: The Environmental Bill for Owning Greenland.