Press releaseAnimal Rescue Out of Habitat Whales

When Walruses Wander: New Study Charts Course for Helping Displaced Marine Mammals

March 26, 2025

A landmark study just published in Marine Policy provides the first clear guidance for responding to the growing number of ‘out of habitat’ marine mammals worldwide.

  • Scientists document increasing cases of walruses, whales, and seals appearing outside their natural habitat – a trend likely accelerated by climate change and human impacts.
  • The groundbreaking study led by OceanCare provides the first clear guidance for responding to “out of habitat” marine mammals.
  • Specialized protocols, improved coordination between agencies, and public education campaigns could help protect the welfare of displaced marine mammals and human safety.

An international team of scientists is urgently calling for improved preparation and responses to marine mammals appearing in unexpected locations, according to a groundbreaking study published this week in the prestigious journal Marine Policy. The comprehensive research brings together experts from six countries to address the growing phenomenon of “out of habitat” marine mammals – from walruses appearing on European beaches to whales swimming up rivers.

Laetitia Nunny, lead author of the study and Senior Science Officer at OceanCare, explained:

“With climate change and other environmental challenges, we are going to see more cases of marine mammals appearing in areas which can be considered ‘out of habitat’.

“We need to prepare for these situations in advance so that both animal and human welfare can be fully protected. Very careful responses are needed as these animals may present major challenges to local communities, but the animals’ welfare is also important.

“We need to recognize why this is happening and that it is not the animals’ fault. Some of these animals may also be important pioneers for their species as they try to find new suitable habitat.”

The study documents numerous recent cases including Atlantic walruses traveling thousands of kilometres to European shores, leopard seals in New Zealand urban areas, and beluga whales far upstream in rivers. These events often generate significant public interest but can lead to misguided responses, including inappropriate capture or even killing of healthy animals.

The research identifies several factors potentially driving this phenomenon:

  • Climate change and extreme weather events
  • Underwater noise and disturbance
  • Changes in prey availability
  • Habitat loss
  • Illness
  • Population growth

Mark Simmonds, also an author of the paper, and Director of Science at OceanCare, added:

“This is the first comprehensive scientific assessment of out of habitat marine mammals ever published in a peer-reviewed journal. By gathering case studies from across the globe, we’ve identified a growing phenomenon that requires thoughtful, coordinated responses from communities and authorities who encounter these animals. With proper preparation, we can ensure better outcomes for both the animals and the people involved.”

The paper provides specific recommendations for authorities, NGOs, scientists, and volunteer groups on how to prepare for and manage these situations. These include developing specialized legislation, protocols for monitoring and intervention, and guidance on appropriate public communication strategies.

ENDS

Notes to editors

An “out of habitat” marine mammal is defined as either an individual outside of their natural range or an individual within their natural range but in habitat that is not optimal for their health and survival due to unsuitable conditions and/or potential conflict with humans.

Recent high-profile cases include four Atlantic walruses (nicknamed Wally, Freya, Stena, and Thor) that appeared along European coastlines, gray whales spotted in the Mediterranean Sea, and multiple instances of cetaceans swimming far upstream in rivers.

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