Out of Habitat: Why are marine mammals being found far from home more often?

Marine mammals are increasingly turning up out of habitat, sometimes in dramatic and unexpected locations. From walruses in Europe to leopard seals in New Zealand, these surprising encounters raise serious concerns about how we respond to such situations. A newly published scientific paper on this topic, highlights the growing issue and provides recommendations to the relevant national authorities to help them prepare in advance for out of habitat marine mammals.

What could be the reason for these unusual phenomena?

A team of international scientists, led by Laetitia Nunny, Senior Science Officer at OceanCare, has compiled extensive research on this phenomenon. The study examines cases such as beluga whales swimming far up rivers, leopard seals appearing on beaches and boat ramps in New Zealand, and great whales found in unexpected locations. While the exact reasons are often not known, potential contributing factors include:

• Climate change and extreme weather events altering ocean conditions
• Noise pollution and disturbance disrupting navigation and behaviour
• Changes in prey availability forcing animals to seek food in new areas
• Habitat loss due to environmental degradation
• Illness affecting an animal’s ability to navigate
• Population growth leading to range expansion

The need for a thoughtful response

Some animals may also be pioneers, exploring new environments that could become vital future habitats for their species.

Laetitia Nunny emphasizes: “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 recognise 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 suitable new habitat.”

Recommendations for authorities and the public

The study outlines key recommendations to help national authorities and communities better manage such encounters. This could include the development of specific legislation or, at least, codes of conduct and protocols which detail how to manage the animals and how to communicate with the public and other relevant stakeholders.

By planning ahead and adopting informed strategies, we can mitigate risks, avoid unnecessary harm, and contribute to the safety of marine mammals facing unprecedented challenges.

Link to the full study

Out of habitat marine mammals – Identification, causes, and management recommendations

Authors

Laetitia Nunny, Mike Bossley, Rebecca M. Boys, Philippa Brakes, Tilen Genov, E.C.M. Parsons, Katharina J. Peters, Naomi A. Rose, Claire A. Simeone, Karen A. Stockin, Courtney S. Vail, Krista van der Linde, Ingrid N. Visser, Mark P. Simmonds