The humpback whale “Timmy,” stranded in Germany, made headlines for weeks. But his story is not a tragic individual fate. Around the world, marine mammals are increasingly finding their way into areas that are far away from their original home and are often unsuitable for their survival. This is suggested by a study that asked experts around the world about cases in their region. 42 species of marine mammals were spotted outside their usual habitats, including Arctic walruses in temperate European waters and whales in the Thames and Seine. Climate change is considered the most important driver.
In March and April 2026, millions of Germans followed the fate of the humpback whale “Timmy,” which got lost on the German Baltic Sea coast and kept getting stranded despite numerous rescue attempts. The walrus “Magnus” is currently attracting attention in Scotland and is repeatedly spotted on Scottish coasts far south of its Arctic home. But these animals, which the public gives names and whose fate is followed in the media, are only a small part of the numerous marine mammals that appear around the world far from their habitats and in many cases die.
Global phenomenon
To get an idea of the extent of the problem, a team led by Maia Killian from the University of Bristol in Great Britain has now interviewed numerous experts from the fields of marine conservation, whale watching and marine mammal research about their experiences with so-called “out-of-habitat” cases of marine mammals. “Using questionnaires and case studies, we learned about 42 different marine mammal species affected,” the team reports. “This suggests that this is a global phenomenon affecting at least 34 percent of all known seal and whale species.”
This is particularly visible in species that suddenly appear in unfamiliar regions: in recent years, walruses have repeatedly been spotted far south of their Arctic habitat in temperate European waters. A minke whale swam as far as London, an arctic white whale (beluga) was also documented in the Thames, and a killer whale in the French Seine. In Peru, Galápagos fur seals – an endangered species – have now settled in their third generation on an island that is around 1,800 kilometers away from their homeland.
Climate change as a cause
Many of the experts interviewed said they believe such events are increasing. They see the most important cause as the effects of climate change. “Marine mammals react sensitively to changes in their environment. When sea temperatures, food availability and habitats shift, these animals are forced to look for new areas,” explains co-author Laetitia Nunny from the marine conservation organization OceanCare. “It is now crucial to adapt protection and response structures to this new reality in order to protect both the well-being of animals and people.”
So far, the handling of such cases has been inconsistent. Only 40 percent of the experts surveyed considered their local authorities or rescue networks to be sufficiently prepared. Large marine mammals can pose challenges for rescue teams, especially in densely populated areas. According to OceanCare, successful handling requires not only specialist knowledge, but also clear processes, resources and training, including in dealing with possible conflicts between humans and animals.
“When walruses appear on Europe’s coasts and whales appear far outside their habitats, these are not strange isolated cases. They are a reminder of how much the oceans are already changing,” says Kilian’s colleague Mark Simmonds. “The study now documents for the first time that this phenomenon occurs globally – and needs to be taken much more seriously.” OceanCare is therefore calling for better international recording of such cases, clear protocols for rescue operations and a consistent reduction in greenhouse gas emissions.
Source: Maia Killian (University of Bristol, UK) et al., Diversity, doi: 10.3390/d18050270