Ocean: how David Attenborough's new film will transform how you see Earth

David Attenborough, naturalist: All life began in the deep blue sea.

Robin Pomeroy, host, Radio Davos: Welcome to Radio Davos, the podcast from the World Economic Forum.

This week, we're talking about the ocean because of the new movie from David Attenborough.

David Attenborough: In this magical world, everything is more connected than we had ever imagined

Robin Pomeroy: I'm joined by Attenborough's co-author and the co-director of the documentary, Colin Butfield.

Colin Butfield, co-director, Ocean: Ocean itself was a sort of a passion project to David. Is there an arc here we can tell over his lifetime, over a hundred years that feels really fresh?

Robin Pomeroy: There's beauty, there's ugliness, but there's also hope.

Colin Butfield: We talk about tree planting and protecting the Amazon. Of course, that is a good thing. But if we applied the same logic to the ocean we could have some of the biggest impacts in reducing our climate impact at generally no cost because with the ocean, you just need to leave it alone.

David Attenborough: For once you’ve truly seen the sea, you’ll never look at Earth the same way again

Robin Pomeroy: The unmistakable voice of David Attenborough, the British broadcast who's been telling the stories of our planet for decades, introducing his latest film called Ocean, released just ahead of the UN Ocean Conference, which is happening as we publish this episode of Radio Davos.

To discuss the movie and an accompanying book called Ocean: Earth's Last Wilderness, I'm joined by Attenburgh's co-author and the co-director of the documentary, Colin Butfield. Colin, how are you?

Colin Butfield: Very well Robin, very well. Thanks for having me on.

Robin Pomeroy: Thanks so much. I know you're very busy with the launch of the movie, with the launch of your book. Tell us something about yourself and how you came to be involved in making this film.

Colin Butfield: Almost by accident if we're taking it back.

So I started off working in conservation, baseline biodiversity studies, all that sort of stuff. And then over about a sort of 15-year career in conservation, I gradually realised the importance of storytelling, that part of the problem here is that we don't all have a shared collective understanding of what's happening to the planet, but also probably more importantly, the solutions that exist.

So maybe about eight, nine years ago, I started, I'd worked with David for a few years in conservation areas, but then we started working on more bigger communications projects, including actually, I came to Davos with David when we launched the Netflix series, Our Planet, and he received his award, and we did a great session in the main hall at Davos.

So from there onwards, we've been working together on a number of projects, including Prince William's Earthshots. We made a series about that. And David Attenborough, Life on our Planet, his sort of witness statements to the world a few years back.

But Ocean itself was a sort of a passion project to David, cut my co-director, Keith Scholey. We talked about it about four years ago, is it possible to do a very fresh look at the world's ocean? And David obviously is famous for having done Blue Planet and other things that really look at ocean wildlife, but is there an arc here we can tell over his lifetime, over a hundred years that feels really fresh? And it's most importantly, I suppose, deliberately designed for cinema for an audience that doesn't necessarily know any of this. So trying to take you on this big arc over a hundred years. And gradually it started to happen.

Robin Pomeroy: And it's a beautiful, beautiful film. This podcast is a video podcast. So if you're watching this on our YouTube channel, we'll be putting some of the images that Colin and your team filmed and included in the movie. Apart from being a beautiful thing to look at, I think it will change the way people view the ocean.

It goes through, and also your book here, which I'm holding up for the video. It goes though, you call it the ocean, singular, which, I am familiar with this idea because all the seas of the world are linked to a greater or lesser extent, but also you go through these different parts of the ocean. For lots of us, we know about, we've sat on a beach, we can see the sea, but we're not really aware of much of what's beyond that. And you talk about the deep, this area with what's called seamounts, so underwater mountains, and the unexpected life that's been discovered there, even at great depths. You talk about The Arctic, and you talk the Southern Ocean. And it really, reading the book and watching the film has changed how I kind of imagine those areas in my head.

Let's talk about a few of those things. Let's start with the deep then and these sea mounts. What do we learn from the movie and from the book about the deep and what is the deep?

Colin Butfield: It's a great question. What is the deep is something that's actually the sort of exact definitions trouble scientists for a while.

So effectively the way we think about it is there's a point as you gradually descending through the surface that you get to a point where light stops permeating where where this sort of direct photosynthesis on life stops happening And that's most people define as the beginning of the deep and actually, of course It covers an enormous amount of our planet's surface because the ocean or planets habitable area because the ocean covers two thirds of our planet. The deep is the vast majority of the volume of the ocean. So that is almost by definition the largest habitat on our planet, yet we know almost nothing about it.

Well, certainly we did at the sort of beginning of this arc, which started a hundred years ago, we had very, very little idea of what was there. In fact, two examples that really bring that to life is any map you can see of the world of, even most of the maps you see today, that open ocean area is just blue. You know, on land we might have white mountains and beige deserts and all sorts of delineations to show features. There is just blue. And for a long time scientists thought there was really nothing there, it's empty abyss.

But the more we look and the more science has progressed, the more you realise it's got just this variety of different features, geographical features and habitats as anywhere on land.

There are seamounts as you mentioned. Already, science has mapped over 55,000 seamounts. And these are huge mountains, both ranges and individual mountains, which we know lots of ocean creatures deliberately go to. Migrating creatures have been tracked deliberately following paths that link up seamounts. But we're really only beginning to understand why that might be. And the further we look, the more we see.

There's one example in the book, which is probably my favourite story. So if you forgive me quickly, telling exists. It was, with any big project, you never quite know if it's going to work, and when I was first told this story, that was the moment I thought, God, there's a lot people don't know about the ocean, and perhaps this is how we can tell stories. And it was about a seamount called Davidson Seamount, off the coast of California, quite a few miles off the west of California in the Monterey Basin. And this explorer, a guy called Chad King, who worked for NOAA, still works for NOAA I think. He descended in a-

Robin Pomeroy: That's not, Noah, the Biblical figure. Remind us...

Colin Butfield: Sorry, sorry, sorry. National Oceanographic and Atmospheric Administration. That's why I said NOAA, because it's hard to answer. But basically the American institution, government institution that does ocean research amongst other things.

But his particular role and his team's role was all about deep sea exploration. And they had submersibles, both manned and unmanned, that were going down to explore the deep. And these are experts, these are people who explore the deep for their job and are well qualified to do so and he put down a submersible in this area off Davidson's Seamount about two and half thousand metres, 2.5 kilometres down and there they're shining these lights around of course there's no natural light you can't genuinely pitch black and they're shining these huge torches around and this starts to see these things that look like footballs, or soccer balls in American language. And wondered what they were and they got closer and closer and they realised there were hundreds of them and as they shone their torches around over in the next period of time they realised there were thousands of them and they said they got closer, they realised these were all octopus they were all female octopus they were, all upside down and for anyone who doesn't know octopus are usually solitary creatures they don't hang out together routinely they get together for specific reasons breeding usually um these were, female and they were brooding or giving birth.

And there were tens of thousands of them. And they've discovered over several dives that they all found these kind of deep sea seeps, these warm water vents that just made the water down there ever so slightly warmer. And the theory is that that helps them to gestate faster, to brood faster. So they use up less of their body's resources giving birth. We don't know that for sure, but that's thought to be the only real explanation.

And the thing that, A, that's incredible, but, B- sort of the fact that even anyone in the world, the world's greatest experts on ocean exploration, no one could have even imagined that was possible. And then you think, well did that happen just there? Does that happen everywhere in the deep? What other things are down there? And the truth is we just don't know. And that's what makes for me the deep so fascinating and such a pleasure to write about.

Robin Pomeroy: The Arctic, then. When I was a kid, I didn't really know the difference between the North Pole and the South Pole, both great big lumps of ice. And then you learn that actually at the North pole it's just ice, at the South Pole it's a huge continent. And the way you make us look at the Arctic now is because that ice is going to disappear, at least in the summer months, it's this sea, if you're looking down at it, with a couple of connections to the rest of the world's ocean. Tell us something about what we learn about the Arctic.

Colin Butfield: I mean the simplest sort of distinction between the north and south is the Arctic is effectively, well it is an ocean surrounded by land. As you say with those two sort of entrance and exit points or connection points to the rest of the ocean. Whereas the Antarctic is a continent covered in ice surrounded, entirely surrounded by ocean actually.

They both make better sense looking at them from above than they do looking on a flat map. But the Arctic specifically, almost all of that ecosystem is quite a shallow ocean basin of the five great ocean basins that all link together, this is quite shallow basin. It's a lot of the life that lives there, the wildlife that lives there, is dependent upon that fluctuation of ice.

So historically, at least over the last 10,000 years, where our civilizations have blossomed and bloomed, you'd have across the winter months it would freeze over, in the summer months it would gradually decline back, but still some ice present. What we're finding of course with climate change is that the the water is warming, the amount of sunlight coming down on it is not being reflected back by the ice as much as it would have done, causing the water to warm more and the ice to shrink, especially in the Summer months, but even in the Winter month, the ice becoming less thick.

And that's having knock on effects on all of the wildlife that live there and the intersections between them. And some of these are, you know, so I suppose quite tragic effects. People probably very familiar with some of those, but some of those are also sort of almost curious from a biological point of view. You're getting now documented examples of pods of killer whales being able to get into areas they never could have reached before because ice has always blocked their path and getting the prey species who have never encountered a killer whale suddenly finding marauding packs of probably the most intelligent ocean predator there is, sweeping in.

Now, of course, these things are fascinating and interesting scientifically, but these changes, because they're happening so fast, we don't quite know how it's all going to plan out, but there's huge disruption in the balance of life within that ocean basin.

And those changes are going to have significant ripples all around that region. So is that, I mean, it's it is people called it sort of ground zero for climate change. I think that's that's probably fair description, there is something nowhere that's changing as fast as this on the planet.

Robin Pomeroy: And tell us about the Antarctic, the fact that this is a continent surrounded all the way around by a cold sea. And you describe in the book why that remains cold and there's a point in the seas there that makes the ecology of the area of Antarctica quite different from the seas beyond that point. Tell us something about that.

Colin Butfield: Yeah, I mean, again, this was a really fascinating thing to write about, because one of the points we found in the research was, which sort of, I guess, puts how wild a continent and the Southern Ocean, that it really is, is that if you imagine a time when, you know, London where I live, it had Buckingham Palace, Oxford Street, a lot of buildings that we know are famous that already existed at a point when no one even knew whether the Antarctic continent existed, because nobody had been able to sail down to it to find out if it was there.

And that's primarily because the distance between most of where the civilizations were at that time, but also because just how wild it is.

And again, the way to picture the Antarctic is look at it from above. So you've got this continent, you've go this ring of ocean going the entire way around. It's the only place where you can directly circumnavigate the entire ocean of the world or the entire span of the world without touching landmass or passing landmass.

And the ocean goes round it incredibly fast, incredibly strong currents. The winds there are the highest on the planet. The waves there are amongst the highest on the plan, But as you said, Robin, there's the point there, which is known as the Antarctic convergence. And this is actually a very real biophysical area. It moves all the time since it's in the ocean, but there is actually point where the colder waters surrounding the Antarctic continent are met by the warmer waters coming in from the other ocean basins flowing into it. And again, it makes much more sense looking from above, but you're getting warmer water flowing in.

The Antarctic Convergence, because of the huge current spinning around the entire Antarctic content, keeps a barrier between where it's much colder on one side, much warmer on the other. So most wildlife actually doesn't cross that barrier. So you get very, very distinct wildlife as you cross the Antarctic convergence.

And the temperature change is so profound actually that when some of the early explorers went down that way they would find as they crossed the Antarctic Convergence the livestock and things they had on board would often die because the temperature change and condition change was so profound and this of course affects the animals that live there as well so some are very specialised to live within the one side of the Antaractic convergeance, others on the other.

Robin Pomeroy: Now, as well as the great beauty in the film, there is also some ugliness. And let's maybe look at this clip, and I think a lot of people will have seen some of this already. It's done the rounds on social media. And it is this, I mean, of the many threats facing the ocean, this is the one that's so graphically shown in the movie, and it is bottom trawling.

David Attenborough: From the surface, you would have no idea that this is happening. It has remained hidden from view until now.

A modern industrial bottom trawler scours the ocean floor with a chain or metal beam, forcing anything it disturbs into the net behind. It smashes its way across the seabed, destroying nearly everything in its path. Often, on the hunt, for just a single species. Almost everything else is discarded.

Over three-quarters of a trawler's catch may be thrown away. It's hard to imagine a more wasteful way to catch fish.

Robin Pomeroy: Colin, for people who are listening rather than watching this, maybe you can describe what is bottom trawling and what we were seeing there.

Colin Butfield: Yes, bottom trawling is sort of a slightly catch-all, excuse the pun, accidental pun, but for a way of describing, essentially dragging heavy equipment across the ocean floor. Usually a beam or sometimes if it's called dredging, it can be metal spikes, but essentially the process of dragging something across the ocean floor and with a vast net behind it such that all the wildlife in front of it is gathered into that net. And it's an extremely indiscriminate way of catching things. So as well as obviously, and very graphically as anyone who's watching could see in the clip, disrupting the ocean floor. So it's, and it's been described to me as somebody giving an analogy the other day that it's sort of like clear cutting a forest to catch a deer. It's, if you try and imagine that visual equivalent, that sort of the thing that you're looking at.

Robin Pomeroy: It's something I wasn't aware of. I mean, I knew about trawling and happening at a large scale. You think of a boat with a big net coming out the back of it, and they go along and scoop up what's in the water. But this is on the floor of the sea, scraping the bottom of the sea, which isn't just like a sandy beach. There's all kinds of life and stuff that's been growing there. Why would anyone do that? What are they getting from that?

Colin Butfield: The extraordinary thing about this, I mean, like you, I knew the phrase, I know a little bit about it, but I'd never seen it before, I'd have never seen images of this four years ago when we started this.

The scale, it is all across most of the coastlines. I'm recording this in the UK, it happens across most the coastline of the UK including about 90% of the marine protected areas in the UK. And generally that's also patterns replicated in other countries, obviously not quite as familiar with the numbers in other country, but that's not unusual for a coastal country.

Often that's done by big industrial trawlers. Sometimes it's smaller boats, but generally it's quite big boats. I mean, simply put, the benefit from a trawler's perspective is that you can catch absolutely everything in one go. So there was an efficiency to it in the short term.

Of course, the downside is that what you're doing is destroying, using an economic comparison, you're destroying the capital.

By doing all of this, you diminish the possibility for recovery, for life in the ocean to replenish. And often trawlers end up throwing away a significant amount of their catch. One of the recent estimates in a United Nations publications was 75% of all the marine life caught by a by a bottom trawler is discarded. Is an incredibly wasteful way to do it, which is why you generally find it done by boats not from communities that live in those areas, because they can move on to the next place. Whereas if you were really relying on that fish to feed your family, that might help you for a year or two, but that's not a good long-term way to be able to continue to fish.

Robin Pomeroy: But some of the most striking images of the film show that contrast between these industrial boats and then the local fishers, people going out often in canoes or ship or fishing just off the beach, and you can actually see them together in the same shot. And then also in the Southern Ocean, those images you have. These boats competing with whales for the krill.

Colin Butfield: Just one thing you mentioned about the sort of comparison with the fishing community. So I think that's one important thing you don't mind just to bring up, which is that, I mean this film was never going to be anti-fishing. I'm not anti-phishing. David definitely isn't anti-fishing.

I think what we wanted to do was reveal the difference between what most of us think of as fishing, which is, you know, boats, four or five people on it going out from your local harbour. I've got a harbour maybe 10 miles south of where I am. These are generally small boats with people that live in those communities. They have a fraction of the fishing quota. Again, in the UK, it's less than 10% of the fish in quota.

The vast majority of the fishes caught are caught by, as you were describing, Robin, those big, giant industrial boats. And most people don't think that. So the Antarctic one that you mentioned, so one of the very interesting things about Antarctica, partially based on what we were discussing a minute ago on the way that that ocean functions, is that the food chains, they're often much simpler than they are in other parts of the ocean.

Nearly everything originates with krill, which is a tiny pink crustacean, looks a bit like a shrimp, and it lives in its billions around the Antarctic ice shelf and within the Antarcitic convergence area. And almost everything, at some point in their food chain, relies on krill. That's the penguins diving in and grabbing it, or it's the great whales coming through, or almost any other food chain in the Antarctic. So it's fundamental to that food chain.

So now, recently... It did happen back in the 70s and it's resurging again. These enormous trawlers, for anyone who hasn't seen the film, these are amongst the biggest ships on the sea. Absolutely vast, dragging these huge nets behind them, pulling up enormous quantities of krill, which is then predominantly used for pet foods, health supplements, and feed for fish farms. So this is not food that's going to some family to cook for dinner that night. This is being used in other products, canned on board given pet food, stuff like that.

And it's starting to happen at a bigger and bigger scale, quite obviously because there's less fish in other places to do so, so it's becoming economically viable or governments are subsidising these fleets to go down there to do that.

And there's a risk that if you continue to push this at scale, if it continues to grow, and the history of fishing tends to suggest we do that, as we start to exploit a stop we often go too far, that could disrupt an entire food chain within the Antarctic.

Robin Pomeroy: And you mentioned marine protected areas and there's a part of the film that is off the coast of the UK, the Isle of Arran, right? Arran that's right. Again, shocking images, the beauty of the ocean floor there before and after. If that's a marine protected area, well, what protection is it getting?

Colin Butfield: Well, actually, Arran's a really fascinating example. And we didn't want to make the film too much about the UK because it's obviously trying to tell the global story. But actually, the interesting thing on Arran, or around Arran, sorry, is that a lot of the area was trawled for scallops and people who've watched the film will see that and the destruction of that.

But the community, including the person that's on film, the protagonist that's in film, actually have set up a genuine marine protected area off the coast of a small part of Arran. And the recovery there has been extraordinary. That's been a no-take site.

But the bigger picture, unfortunately, is areas that are genuinely no-take zones, in other words, where nothing is caught, or even where only hook and line, very small amounts of fishing that does not destroy the base, are incredibly rare.

Again, in my country, maybe only 10% of the marine protected areas, well, in fact, actually only 10%, of the marine protected areas have banned bottom trawling. So that means 90% of a marine protected area across the UK's waters allow bottom trawling.

Robin Pomeroy: So in what way are they protected?

Colin Butfield: Well, exactly the question. So the definition, this is partially one of those terminologies that then gets misused. So in some cases, it might be because they're being protected for a seabird or for a particular type of fish or a particular reef, but the rest of the area is a free-for-all.

And of course, that's a fallacy because you might protect, let's say, a seabird and a seabird colony, but you can dredge the bottom. Remove the source of the food. And then presenting those as we have more than 300 marine protected areas isn't that great. It gives the public the impression that they're protected like an ancient forest might be or a mediaeval cathedral. It's protected. Of course, it's not.

And I think that's one of the big debates heading into the UN Oceans Conference that a marine protected area, if we're going to count them amongst our own quotas as countries to bring to the world, should be a marine protected area. And that's what, within those no-take designs, the recovery is extraordinary.

Everywhere we've documented it, there's loads of examples in the book that we didn't have the space in the film to feature. And in every case, they've been supported by the fishing community locally. And in case the recovery has been extraordinary of marine life and people have actually had better longer term livelihoods as well as all the other benefits that come to the environment.

Robin Pomeroy: Yeah, and that's one of the things about the film and the book is that there's beauty, there's ugliness, but there's also hope. And probably Colin in your work communicating these issues, you found, I'm guessing, you can't just tell everyone it's doom and gloom. If there is hope, you have to go out and fly the flag for it. And I think you really do that.

And David Attenborough does that. As you say, he's approaching a hundred years old now, he's 99 right now, and he, you know, he's very clear about that. He won't have that much time left. And he says, I don't know how this story ends, but even says, even his lifetime, there's been so much damage to the environment, which he's spent a career documenting, but even he has seen hopeful signs.

And he mentions whaling, for example, how that even in his lifetime whales have come back, hunted almost to extinction when he was a baby, 100 years ago, to now, they're still recovering, but in some cases have really come back.

And there's, and as you say, these no catch zones, the example, the big one is, well, there's one off the coast of California and a huge one in Hawaii where it just shows the rapid recovery.

Can I just read you a bit from your own book? This is from a chapter, the final chapter, I think, called A Single Human Generation, which is a curious title for the chapter, but then this is the bit that explains why it is.

"As we have seen already, the ocean can recover, mangroves and kelp forests can regrow, whales can return, and dying coastal communities can flourish once again. Such is the potential for recovery that it is entirely possible. There could be but a single lost generation. We could be the outliers, the ones who unknowingly took too much and protected too little. Just as those that came before us lived alongside an ocean abounding with life and vitality, today's children could grow up witnessing its resurgence. There may be much to fear in the near future, yet it could also be the most exciting time to be alive."

It's very optimistic. Do you think, do you think that's true?

Colin Butfield: It is unquestionably possible, whether it comes to pass will depend on us, but biologically it's possible.

And that's the interesting thing in the book in particular, because we go habitat by habitat and join them together. We look at recovery across mangroves, kelp forests, the open ocean. And what you start to realise in every case where we've protected it, the bounce back has been so much faster than scientists or even the greatest experts in that field, predicted. The ocean continues to surprise us.

The recoveries all across the world that we document have come back very fast. As such, you start to piece that all together and you imagine a world where we protect more than 30% of our coastlines, we protect the seamounts. Not saying don't fish in other places, because obviously not using the most destructive fishing gear, but still fishing in other place. There's every reason to think the ocean will bounce back to the sort of scale that it used to be. And of course, no one alive today has ever seen.

So yeah, but I mean, biologically, there is no reason not to think that could happen. Clearly the decisions lie with us to make that happen.

Robin Pomeroy: So there's that issue of overfishing. There are obviously other perils facing the ocean. Plastic pollution, we've talked about. Pollution in general. But of course then there's also climate change. And what a lot of people won't realise before watching or reading your story is the hugely important role the ocean plays in regulating the climate and absorbing carbon. I'm just looking at a fact here, the British Antarctic Survey describes the Southern Ocean as the world's largest heat and carbon sink. Their studies reveal that almost three quarters of human-induced warming to date has been absorbed by the ocean. So that means if that ocean wasn't there, the land and the air would have heated much more than it already has. And we already know it's heated at the upper end of forecasts when people started forecasting climate change a few decades ago. So, I mean, climate change is also a massive risk here, isn't it?

Colin Butfield: It's exactly right. I mean we would have unquestionably superheated our planet by now had it not been for the benefit of the ocean. Obviously there are lots of other issues in the ocean, but, as an example, the ocean does two things.

It takes in the heat and obviously the worry we have is how much more can it continue to absorb heat anyway, but then of course secondly what will be the effects on life in the oceans if it continue but even with heat gets absorbed but if it continues to absorb more.

Probably most famous case of that is that of coral bleaching. These are essentially caused by any stress placed on coral. This can be pollution as well as heat, but typically it's ocean heat waves sweeping through, which have probably always happened. In fact, that would have certainly almost happened, but they would happen for a brief period of time at a lower temperature than they are now, and the coral can recover quite quickly from that. What we're getting now is such prolonged ocean heat waves, at such high temperatures that coral isn't recovering, it's bleaching and ultimately dying. So that's one of many examples of what happens as the ocean heats.

But the second part of it, of course, with climate change is the ocean's also been absorbing, absorbing some of our carbon dioxide. And it's been, the phrase that people hear is it's acidified the ocean, it's changed the pH in the ocean. And we're already seeing effects on a number of different ocean species, those that use, that make hard shells are struggling to do that because of the different pH within the ocean. You're also seeing those same coral reefs we were talking about earlier having the limestone dissolved within them, which is threatening the very foundation of them.

So we're changing the chemistry of the ocean and where that leads, I don't think we're capable of analysing at the moment, but it's not seeming to be a good thing at the moment.

So it's both our greatest ally at tackling climate change, but climate change is also a threat to it.

I think the one thing that maybe doesn't get enough attention though, as the ocean recovers, as giant kelp forests grow, as seagrass meadows recover, as mangroves extend out, the amount of carbon that gets stored by those that gets drawn down to create healthy ecosystems, not to damage the balance in the ocean, is enormous. It rivals that of terrestrial forests.

So rightly, we talk about tree planting and protecting the Amazon. Of course, that is a good thing. But if we applied the same logic to the ocean we could have some of the biggest impacts in reducing our climate impact at generally no cost because with the ocean, you just need to leave it alone. You could maybe leave it along on an industrial scale, but you need to just leave it. It gets all its inputs from the circulation of ocean currents. We don't have to do anything. We don't have to plant things. We just have to leave that alone and we'll get huge benefits from that.

Robin Pomeroy: And those kelp forests, which we can observe in the movie, are such rich ecosystems. That's another example of how we're based on land. At the start of the film, David Attenborough says, once I learn about the ocean, or once you learn about ocean, you'll never look at the earth in the same way again. We think of the forests, we don't really think about the kelp forest. But as you say, these can rival them in terms of biodiversity and wildlife, but also in this massive, it's a horrible expression, but ability to be a carbon sink, and so much of that, nature, even whales themselves are dragging down carbon and leaving it at the bottom of the sea, which otherwise would be adding to the problem of climate change.

Colin Butfield: Exactly, and whales are an extraordinary example because they show so many different ways in which this happens. You know, kelp forests is another one. But I quite like the whales one because, as you said earlier, we hunted whales, most whales, to the verge of extinction. There was maybe 5% of blue whales left. And this was still happening when I was a kid, you know, sort of in the 70s, late 70s. And then as they started to recover, we of course got the opportunity to be able to study and see what happened as they recovered. You mentioned earlier, they recovered faster, in many cases, faster than we had imagined, especially whales like humpbacks. But we found out two really, really interesting, important things. The first was a thing that gets called the whale pump, which is basically that a lot of whales swim down deep, let's say sperm whales swim down deep feed at the bottom, come at the top and...

Robin Pomeroy: Just how deep? Remind us how far can they go?

Colin Butfield: Oh, I mean, kilometres, kilometres down, they hunt giant squids several kilometres down. They can hold their breath comfortably for half an hour and dive incredibly deep. These huge battles with giant squid, which have lacerations and pulled across the whale's face as it's fighting, I think this is a fearsome, fearsome battle that nobody's ever seen. But it happens every day in the ocean.

Robin Pomeroy: How do you know it happens?

Colin Butfield: Yeah, great question. So two reasons really. So one, all of the sperm whales that have ever been sort of found and monitored have these sort of lacerations that can be easily measured and clearly come from giants or colossal squids. And we find the bodies of giant and colossal squids have been found on beaches. So we know these are real creatures, we know how big they are, we now they have hooks on their tentacles, we know they have fearsome beaks.

But the second one, which is really interesting, is whenever an autopsy is performed on a dead sperm whale, in their bellies there are lots of beaks of giant squid or colossal squid sometimes, and those are in there, so they clearly eat them all the time. We know they eat them, we know they fight them, and we don't know who wins often, but we know these extraordinary battles happen, and they almost certainly happen incredibly deep down in the ocean, but nobody's ever seen one. Greatest fight or hunt sequence anybody's never filmed for a wildlife sequence. So I think we refer to it in the book, but it's an extraordinary thing.

Robin Pomeroy: I interrupted you there, you were talking about the whale pump, was that the expression?

Colin Butfield: Oh yeah, the whale pump. Yeah, sorry. Easy to get distracted of when you're talking about giant squid.

So when the whales, let's say sperm whale in this case, defecates at the surface, its poo sort of super fertilises the sunlit open at the top of the ocean. Photosynthesis works as it does on land. It stimulates growth in microscopic plants, phytoplankton, that's huge blooming and life zooplankton, they're tiny animals, so usually babies of lobsters and fish etc etc, they bloom, you get this, so effectively when you fertilise the top of the ocean it draws down carbon dioxide to grow the microscopic plants and this is happening on an enormous scale, so it's sequestering carbon.

And then the second way that whale pump works is in the circulation of currents caused by the way of swimming and diving. You're again also circulating the carbon dioxide within the ocean and getting it down to depth.

There's actually thoughts that there's a third way as well, which is that when whales die, we hear about the ones that wash up on beaches, but the vast majority of course sink to the bottom. So their own bodies sequester carbon down in the deep and actually form entire ecosystems for the first two or three years it takes for them to be eaten.

Robin Pomeroy: Tell us something about being a filmmaker in the ocean. I mean, you're obviously on the lookout. You know, one of these days, you'll capture that, won't you, the whale fighting a colossal squid? But I mean what's it like for those of us who've never done it, who never will do it, to be out capturing those pictures that we've seen over the years?

Colin Butfield: Well, I think here's where we've got to give enormous credit to, and in particular in this film, Doug Anderson, he's the cinematographer, so it's his, predominantly his, I mean not the others too, but either he shot the bulk of this film. And I think it's really their skill we should talk about here, because what someone like Doug is the best in the world at doing this does is weeks at sea waiting for something, you then get a of a moment where you've got to dive into the water and you've got to... You've got chaos around you, let's say a bait ball or a whale swimming by, for any one of us that got in the water you just get either overexcited or just bewildered by the amounts of activity in this sort of semi-alien environment.

And he manages, as you've seen in the film, to compose gorgeous shots that anybody on land in controlled conditions would be envious of. He gets the light right, he follows the species, say a whale, swimming past or into the bait ball. In a way that he's framing it extraordinarily.

The presence of mind, the diving skill, the cinematography skill to be able to do that is absolutely off the charts. And I think often people like me get to talk about the film, but it's people like Doug that mean it looks the way it does.

Robin Pomeroy: I wanted to ask you when we were talking about the bottom trawling, we watched that clip. How did you get those pictures?

Colin Butfield: Oh yeah, so that was a really interesting and tricky thing.

So when we started making the film, we went through the process of trying to think, okay, there's a lot of issues facing the ocean. How do we focus on a few things that people will really understand? We really wanted to go to a mass public audience rather than specialists in ocean conservation, particularly. So we knew we needed to show the most damaging fishing methods, bottom trawling, boom principle among that. And we just thought, I suppose naively, assumed that this was something that's been going on for decades. It's not a new thing. Happens everywhere. There's got to be footage somewhere and you can just buy it off somebody or ask them to use it. And there isn't. I mean if you go online other than our footage there's a few shaky GoPro camera stuff but there's nothing you could put on a cinema film and that really brings home that sort of visceral impact of it.

So we realised we'd have to film it but that's not, you know, that brings its own complexities. We briefly thought about putting Doug in the water and then realised that killing a second that cinematographer was probably a bad idea. So we ruled that out quite quickly.

And we were very very fortunate. We got to know a scientist at the University of Plymouth, a guy called Bryce Stewart, who's doing research into the impacts of this Because it's been poorly studied again for a practise so common across the world it's being hardly started hardly documented never filmed I mean, it's extraordinary how secretive that is and so he was trying to study what actually is the measurable impacts? This is having on the ocean bed And he was performing some scientific experiments and kindly agreed that we could attach cameras so we could then give him all the footage and his researchers all the footage, but obviously we could use it in the film.

And then the challenge, of course, was trying to build housings for the cameras that would actually survive the sort of violent impact that you see. And we definitely damaged a few cameras. A long way to do that. But actually one of the more interesting things that came out of that process was clue before doing that trawl, we wanted to make sure we weren't going over pristine habitat. So as horrible as that looks, that's over an area that's been trawled countless times. And we put cameras down before the trawl went down just to see what was there and make sure that we weren't going to damage, I mean as horrible it is, but we weren't going damage some pristine habitat. And then we actually found a whole sort of area of pink sea fans that nobody knew was there. So we were able to get that now thanks to the scientists involved, that area's got protected. And we moved to another area that we knew had already been, we could see had already being trawled dozens of times in the past. So it's part of a, yeah, lucky partnership really with some scientists doing some great work that hopefully will be published in the next few weeks.

Robin Pomeroy: That's a moral conundrum then, isn't it? The trawling is going on and that research is going on, but you know, for that scientist, they are doing that damage that we're seeing in the film.

Colin Butfield: Exactly. And I think one of the things that I think give them sort of hope and certainly make it good for us is that we're giving away that footage, not just to the scientists, we're actually giving it away free on a platform we've set up called Open Planet. So a couple of months after the film's gone on Disney and it's been seen, we'll be giving this footage away to everybody. So the point is that nobody ever has to film it again. There's lots of this footage. Everybody can have it for free. We're not going charge for it.

And so it's done once, none of us wanted to do it. Least out of it. We've got scientific data that can hopefully help stop this, we've got footage that's hopefully shocks people and maybe again can hopefully stop it and we're giving away the footage so everybody can use it. So yeah, as moral conundrums go, it's not lovely, but it felt like on balance we've done the right thing.

Robin Pomeroy: Finally then, you set out with a mission, I suppose, making this film, writing this book. What's the one thing, let's see if I'm, you're obviously very good at limiting yourself to focusing on things. As you said, there could have been dozens of other stories you could have told.Is there one thing you would want someone who's watched this film to take away from it? And maybe I'll let you give me two answers. A policymaker like the people meeting as this goes out. In Nice, in France, at this UN Ocean Conference, who should already know more than the average viewer. And what would you like the average viewer to remember from it?

Colin Butfield: Well, for policy makers first, it's an easy one. We should not have bottom trawling in our Marine Protected Areas. We probably shouldn't have them, we should have more Marine Protecting Areas too, but if you're asking me for just one thing, start by ending bottom trawing in our marine protected areas. And they can make that commitment now. They should make it ahead of or at the World Ocean Conference in Nice. And I don't think there's any real excuse. There's public appetite that clearly supports this on a big scale.

Biologically, we'll end up with richer seas, which will benefit all of us. So that's for policy makers, that's in some respects clear and easy. I think it's almost a no-brainer, which is why it's shocking it hasn't happened yet. For the public, it's slightly harder. So I guess my hope is that they realise we're much more connected to the ocean than perhaps any of us had realised only a few years ago. It's so important for the stability of our planet, but it's a wonderful place that's full of great discoveries and and, and, an importance to us. I hope people love the ocean more as a result of this and feel hope that they can have an even richer ocean going forward. Yeah. Possibly join two things together there to get me an extra one.

Robin Pomeroy: No, I think that's one. I think, you know, and that is the quote I read out, this idea of... This generation is the aberration, and we can return to something from the past. As you say, could happen, like so many things, it just depends on political will and all our will.

. I'm going to draw it to a close, I think. Is there anything you think we should mention that... I mean, obviously there's a million things, but... No, Robin, I'm really happy I think this...

So, the film is called Ocean with David Attenborough, I believe. Is that right?

Colin Butfield: That's right.

Robin Pomeroy: Where can people see that?

Colin Butfield: It's in cinemas in quite a few places, but it's coming onto Disney and National Geographic on worldocean.edu now.

Robin Pomeroy: And the book is called Ocean, Earth's Last Wilderness by David Attenborough and Colin Buckfield. Colin also co-directed the movie.

Colin Butfield, thanks so much for joining us on Radio Davos.

Colin Butfield: Pleasure Robin, thank you for having me.

Robin Pomeroy: Thanks to Colin Butfield and thanks to Silverback Films and Ocean Planet Studios for those images. This episode of Radio Davos was written and presented by me, Robin Pomeroy. You can find all our podcasts at wef.ch/podcasts and anywhere you get your podcasts and you can watch this episode on our YouTube channel.

Radio Davos will be back very soon. Please do join us then. Thanks to you for listening and watching and goodbye.