The Arctic is warming faster than the global average, and scientists are searching for better ways to understand how wildlife is responding. A new study from Svalbard suggests that the answer may lie in the water itself.
Researchers working along the western coast of the archipelago used environmental DNA, or eDNA, to survey marine vertebrates across a range of Arctic habitats. Every animal leaves traces of genetic material behind through skin cells, mucus, scales, or waste. By filtering seawater and sequencing the DNA it contains, scientists can identify nearby species without capturing or disturbing them.
During a ten-day expedition in June 2025, the team continuously collected seawater samples at 16 sites along the western coast of Svalbard, including glacier fronts, walrus haul-out areas, harbors, shallow coastal zones, and offshore waters. The survey revealed 36 different vertebrate groups, among them fish, seabirds, seals, whales, and even traces of terrestrial animals such as Arctic foxes and reindeer detected near the shoreline.
What surprised the researchers most was how different neighboring habitats turned out to be. Rather than finding the same species throughout the region, the study revealed a strong turnover of communities from one environment to another, even across relatively short distances. Harbors and walrus haul-out sites contained especially rich and evolutionarily diverse assemblages, while glacier-influenced waters were dominated by fewer, more closely related species. Glacier sites also hosted several distinctive Arctic taxa, including black-legged kittiwakes, Arctic terns, harp seals, and minke whales.
(Figure: Haderlé et al. 2026, Polar Biology)
Some detections may reflect the growing influence of climate change in the European Arctic. The presence of species such as harbor seals and three-spined sticklebacks is consistent with broader ecological shifts linked to warmer Atlantic waters moving northward into Svalbard.
The study also showed that eDNA methods can work reliably under difficult Arctic conditions. Many of the genetic detections matched visual sightings and acoustic observations made during the expedition, strengthening confidence in the approach.
The findings highlight both the fragility of Arctic ecosystems and the challenge of studying them. Much of Svalbard is protected, field campaigns are expensive, and wildlife surveys are often constrained by weather, sea ice, and remoteness. In that context, eDNA offers a remarkably simple idea: seawater can serve as a biological archive of the animals moving through it. As the Arctic continues to change, those invisible traces may help scientists detect ecological shifts long before they become obvious to the human eye.
Léa Zinsli, PolarJournal