The effects of global warming depend on species: the losers are legion, but a lucky few are winners. Now, researchers have shown that baleen whales are taking advantage of a newly opened-up fish bonanza in the Greenland Sea, due east from Greenland and reaching to the Arctic Circle and beyond.
“Here we show that rising ocean temperatures and declining sea-ice cover have facilitated the widespread occurrence of baleen whales along the East Greenland coast, as far north as 70°N,” said Prof Mads Peter Heide-Jørgensen from the Greenland Institute of Natural Resources. “This has led to regular mixed ‘feeding frenzies’ of fin whales, humpback whales, and common minke whales – species which historically were only rarely observed in coastal East Greenland.”
Heide-Jørgensen and colleagues in Greenland, Denmark, and Iceland have documented this latest spectacle of the natural world in a study in Frontiers in Marine Science . They emphasized that it could spell major changes up and down the local food chain.
The Arctic and North Atlantic – apart from a puzzling ‘cold blob’ south of Greenland – are some of the fastest warming regions on Earth. For example, sea surface temperatures east of Greenland have risen by approximately 2°C since the 1990s. The ice edge in summer retracted far to the north after the mid-2000s, dramatically reducing the extent of pack ice along Greenland’s east coast.
First systematic surveys
The authors conducted the first systematic survey by plane of baleen whales up to 50km off the East Greenland coast in August 2015 and in 2024. They added further airborne observations in the summer of 2022, testimonies from Inuit hunters between 2023 and 2025, and records from ships taking part in North Atlantic Sighting Surveys from 1987 on. They also analyzed tracks from 15 satellite-tagged baleen whales taken at intervals between 2019 and 2025. They then built a mathematical model to find patterns within this sea of data, using historical measurements from key factors like sea-surface temperature, salinity, and icepack concentration to explain the variation.
Together, the results give a unique record of changes in the abundance of baleen whales in the Greenland Sea over the past three decades.
The picture was uniform: between 1987 and 2024, there has been a marked change in the occurrence of baleen whales along the East Greenland coast north of 60 °N and west of 29 °W. For example, ship-based surveys didn’t observe any humpback whales until 2006, while seven sightings were recorded in 2007, 26 by 2015, and more than 150 by 2024. Similarly, sightings of minke whales from the survey vessels were few until 1995, but between 10 and 20 were encountered year-on-year after 2001. Ship-based sightings of fin whales likewise increased sharply from 1987 to the present day. In August 2025, a ship crew reported meeting exceptionally large aggregations – of up to 50 individuals simultaneously – of baleen whales along the east coast around 69 °N, thus north of the Arctic circle. Likewise, the systematic airborne surveys documented an almost continuous distribution of all three species at the same time between 60°N and 70°N in 2015 and 2024.
A fish called capelin
Heide-Jørgensen and colleagues estimate that altogether, no fewer than 4,000 humpback whales, 6,000 fin whales, and 6,000 minke whales visited the Greenland Sea in the summer of 2024.
“There is little doubt that the three baleen whale species summering in East Greenland coastal waters do so primarily to feed,” observed the authors.
But what might bring them to the region in these staggering numbers? The authors found that the trio visits the region mainly to hunt for capelin – a cold-loving fish and known to be one of their most important prey further south. Capelin have recently been shown to have shifted their feeding grounds since the mid-2000s from the relatively warmer waters north of Iceland towards the Greenland Sea. The conclusion must be that baleen whales have caught up with this shift and moved in for the kill.
Reassuringly, there have never been any commercial capelin fisheries in this region, so competition with humans doesn’t seem likely for now.
“East Greenland is undergoing a major ecological regime shift. Ice-associated species such as narwhals are increasingly sharing their habitat with, or being displaced by, temperate baleen whales that generally avoid ice-covered waters,” concluded Heide-Jørgensen. “This marked change in species composition demonstrates how climate-driven changes are reorganizing the East Greenland marine ecosystem, potentially with long-lasting consequences.”
Frontiers in Marine Science
20-Aug-2026
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest