"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 Professor Mads Peter Heide-Jørgensen of the Greenland Institute of Natural Resources. "This has led to regular mixed 'feeding frenzies' of fin whales, humpback whales and common minke whales—species that historically were only rarely observed in coastal East Greenland."

Heide-Jørgensen and colleagues in Greenland, Denmark and Iceland 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 among 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 aircraft survey of baleen whales up to 50 km (31 miles) off the East Greenland coast in August 2015 and 2024. They added further airborne observations in the summer of 2022, testimony from Inuit hunters between 2023 and 2025, and records from ships taking part in North Atlantic Sighting Surveys since 1987. They also analyzed tracks from 15 satellite-tagged baleen whales collected at intervals between 2019 and 2025. They then built a mathematical model to find patterns within this sea of data, using historical measurements of key factors like sea surface temperature, salinity and ice pack concentration to explain the variation.