Return of the Leviathans

‘There is, one knows not what sweet mystery about this sea, whose gently awful stirrings seem to speak of some hidden soul beneath…’

Few ocean giants have captured our collective imagination as whales have done; they fill our literature, music and poetry. And, as these words from Herman Melville’s Moby Dick demonstrate, much about them has been made mythical. But for all their size and splendour, we have never experienced most whale populations in the historical numbers that would have awed mariners and launched the large-scale whaling of many species.

However, in a stroke of unusually good news about the ocean, researchers and filmmakers have documented the return of large aggregations of fin whales to their ancestral feeding grounds at the Antarctic Peninsula. One hundred groups of fin whales, comprising up to four individuals in a group, were recorded during dedicated aerial surveys. Other records during the survey period included a sighting of a group of 15 fin whales feeding together with Antarctic fur seals and chinstrap penguins. Yet more reports of sightings of fin whale groups 50 to 70 animals strong were astounding, as nothing like them exist for any other region on earth.

‘This feeding aggregation is one of the most spectacular sights I have ever witnessed in almost 20 years of ocean exploration and filming,’ says Dan Beecham, an underwater videographer who filmed the events for the BBC Natural History Unit. ‘The scale of the event is almost unimaginable. It feels like travelling back in time to the great ages of exploration when the famous explorers of old would have come across events like this while they were charting “new worlds”. Sadly, at that time such discoveries would have resulted in unsustainable hunting, which is what reduced the population of fin whales so drastically until the end of commercial whaling in Antarctica. Enough time has passed since then that we are now seeing those populations rebound.’

Whaling during the 20th century led to populations of fin whales being devastated. With more than 700,000 of them killed between 1904 and 1976, it’s little wonder that surveys by the International Whaling Committee between 1978 and 2004 found few fin whales left in the region of the Antarctic Peninsula, the site of most concerted whaling effort. But reports of increasing fin whale sightings began to emerge from the 2000s, with some anecdotes of ‘supergroups’ surfacing. The rumours were enough to launch the surveys that are now documented in a paper ‘Return of large fin whale feeding aggregations to historical whaling grounds in the Southern Ocean’, published earlier this year in the journal Scientific Reports.

‘I travelled to Elephant Island on the Antarctic Peninsula for two different productions, the first being the BBC’s Seven Worlds, One Planet back in 2019, and then again in 2021 for the Disney+ series Epic Adventures with Bertie Gregory,’ explains Dan. ‘As a freelance underwater cameraman, my role on these shoots was to film the fin whales feeding underwater, alongside a host of other predators – penguins, fish and seals. Footage and still photos from these shoots, including drone footage, were used in a scientific assessment of the return of this population of whales – a nice opportunity for media and science to collaborate.’

A return of whale numbers is heartening, but even more exciting is the re-establishment of past behaviour. By returning in large numbers to their historic feeding grounds, fin whales can once again become part of the nutrient cycle. Dubbed the ‘whale pump’, they can help recover critical ecosystem functions such as carbon storage and nutrient enrichment, according to researchers. And yes – that means that fin whales are enriching Antarctic waters with their faeces. Whales dive – often very deep – to feed and they return to the surface to breathe and to release what scientists call ‘flocculent faecal plumes’. In effect, they bring to the surface the nitrogen, iron and phosphorous that have sunk into the deeper reaches of the sea with their prey, making these elements available to plankton and other marine creatures.

In addition, as whales feed, throughout their lifetime they accumulate stupefying amounts of carbon in their bodies. When they die they sink into the deep ocean, locking away with them the carbon consumed at the sea’s surface – and therefore helping to lock away excess carbon that otherwise warms our ailing atmosphere. The return of fin whales, therefore, is good news for our climate – and for us. ‘There is so much doom and gloom in the world these days that good news stories, particularly about the environment, can be hard to come by,’ notes Dan. As someone who works to tell the stories of our oceans, seeking out hope is a necessary but often difficult task. ‘At times it can be hard to be optimistic about the future of the ocean, but this event shows that the ocean is resilient and it will rebound – if we are just able to leave it alone for long enough.’

If the history of whaling has taught us one thing, it’s that the potential loss of species has frightening consequences – and we stand to lose functions and services we don’t yet fully understand. But whales have also taught us that there is something less practical to extinction that is equally painful. As Callum Roberts writes in his An Unnatural History of the Sea, ‘Extinction, the irrevocable loss of a species, causes pain that can never find relief. It is an ache that will pass from generation to generation for the rest of human history.’ Losing ocean citizens like whales would mean losing something of ourselves – and perhaps that’s what the writers, poets and musicians who have drawn inspiration from them throughout history have always understood.

Dan believes that there is good that can be translated from these findings into direct action. ‘It would be great if this example of an ecosystem rebounding can act as an example of how marine protected areas can and do work – there are other examples in the world. But in many instances making somewhere a marine protected area on paper is not enough. These areas need policing as well as just being protected on paper.’ The Antarctic Peninsula has been earmarked for protection as part of the expansion of marine protected areas around Antarctica. The region represents one of the last very wild places on our planet, a feature that perhaps helped the recovery of fin whales. ‘The fin whales in Antarctica benefit from being so remote and being such an iconic species,’ agrees Dan. ‘But many other areas and species are in just as much need of more protection and policing to help ensure a bright future for them.’

**References: Herr H, Viquerat S, Devas F, Lees A, Wells L, Gregory B, Giffords T, Beecham D and Meyer B. 2022. Return of large fin whale feeding aggregations to historical whaling grounds in the Southern Ocean. Scientific reports, 12(1), pp.1-15.
DOI: https://doi.org/10.1038/s41598-022-13798-7