Mark Peter SimmondsDirector of Science
Finding a marine mammal far from its natural range seems to be a growing phenomenon.
When the walrus comes knocking: a reflection on Wally and other out-of-habitat marine mammals
What do you do if a walrus suddenly turns up in your ‘backyard’ far from its natural home? This is a dilemma that many people have been facing over the last few months as the world’s most famous walrus, Wally, made his grand tour of Europe. During his travels, he went as far south as Spain and also visited France, Wales, England and Ireland. Responses to his presence were varied. Initially, he was welcomed in some places, and sometimes as a great new tourist attraction. Tourist boat trips went out to see him and people even tried to take selfies with him, a high-risk ambition given that he is wild, unpredictable and massive (about one tonne in weight). As he developed a habit of hauling-out onto small boats damaging some and, in a few cases, sinking them, calls that he should be urgently moved on (or even killed) followed. He changed in a matter of hours from being a popular curiosity to being an unwelcome menace. But who was responsible for dealing with him?
In the UK, where he probably lingered the longest, including in busy St Mary’s Harbour in the Scilly Isles, it was local volunteers and the voluntary animal rescue community led by British Divers Marine Life Rescue (BDMLR) who stepped up to try to address the situation. They all had to take a self-taught crash-course in walrus biology – consulting widely with walrus experts around the world – and ultimately came up with the inspired idea of giving him a specially-designed floating pontoon to rest on. This worked well. A plan to try and capture him and fly him north was also seriously contemplated. When he moved to Ireland (his most recent move but one), the boat damage and other problems travelled with him and, again, a special pontoon was successfully deployed.
The importance of hauling out – which in his native Arctic this would be onto ice floes or the shore – is that like other pinnipeds (seals, sealions and walruses), he needs to be able to rest out of the water. In fact, these animals need a lot of rest (they are not just lying around being lazy) and – like most of us – they like to do this undisturbed. People driving boats up to his rest area to peer at him or try to get photographs would have disrupted his rest. Moreover, there was also a reasonable theory that if he could get enough food and rest, that he would develop a good layer of fat and be more able (and likely) to move off back to the north. The most recent reports locate him in a harbour in Iceland seemingly heading in the right direction for his natural habitat.
The occurrence of a walrus so far to the south of their normal range is highly unusual, although there are recent reports of another one on the coast of continental Europe. However, finding a marine mammal far from what is typically thought of as its natural range seems to be a growing phenomenon. Examples include dolphins and even large whales venturing into river systems, leopard seals venturing into suburbia in New Zealand, elephant seals ‘lurking’ in unusual places, dolphins in the Venice lagoon and a growing list of beluga whales turning up far from their Arctic habitat. Predominantly, the focus on these animals is on their welfare – in some busy harbours, they might get struck by boats for example – and whether they need to be taken ‘home’ for their own wellbeing. Sometimes, however, there are genuine concerns for human safety. For example, many big marine animals can inflict serious bite wounds or other injuries with their powerful tails – a particular concern if one foolishly tries to sit on one for a selfie!
In some countries, for example the USA and Canada, government agencies will help to respond to these often very perplexing situations. In most parts of the world, however, no such government-funded help exists and, therefore, the pressure on national or local organizations like BDMLR to respond can be considerable, especially when the public don’t understand or appreciate what is happening. For example, monitoring is often the best response, giving the animal the opportunity to work its own way back to better circumstances but may appear passive to the general public. Sometimes, animals that appear to be outside their natural habitat, even in strikingly unnatural situations, are able to feed and stay healthy. Such proved to be the case of the beluga in the River Thames in London in 2018-19. Whilst there were real concerns about the boat traffic and disturbance going on around him, there was no immediate need to attempt a rescue. This brings up another consideration. Catching and moving a large marine mammal can be life-threatening to them and also dangerous for the people involved. Such interventions have to be very carefully thought about, planned meticulously and informed by the advice of experts.
The ‘Thames beluga’ is one of several of these striking white Arctic whales that have been seen far from home in recent years. The latest (seen this week) is in Puget Sound in Washington State in the USA, far from its home in the north. It is possible that for some belugas dispersal from their primary habitat areas is within the range of their normal behaviours. This seems far less likely for a walrus or some other recently recorded wanderers. Some animals moving outside of their normal range could be unwell or wounded – their behaviour driven by pain, fever or some aberrant psychology. Others may have been driven away by the loss of habitat (for example melting polar ice) or even some noisy human activity. The sea offers no solid boundary to the dispersal of marine mammals and, whatever the causes, we do seem to be seeing an increased frequency, meaning we need to be increasingly well prepared to respond. Hopefully, Wally’s story will have a happy ending and he will swim north from Iceland and be reunited with his own kind. The prodigal walrus returns!