Episode 37: Exploring pristine seas

National Geographic Explorer Enric Sala is on a mission to protect almost a third of the world’s oceans by 2030.

A Galápagos sea lion chases a large school of salema fish off Isabela Island. Punta Vicente Roca, Isabela Isla, Galápagos Islands, Ecuador.
Photograph by Enric Sala

National Geographic Explorer in Residence Enric Sala quit academia to explore and protect the sea. On his journey to keep the ocean pristine, he has swam with jellyfish in Palau, gone diving in the Arctic, and got acquainted with sharks at Millennium Atoll. Sala’s explorations have led to 24 marine preserves—with a combined area more than twice the size of India. But the hard work is far from over, as Sala aims to protect 30 percent of the world’s oceans by 2030.

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(Chatter of penguins)

ENRIC SALA (CONSERVATIONIST): We were filming this colony of rockhopper penguins. And then all of a sudden, we see the water boiling offshore. Wow, what’s that?

AMY BRIGGS (HOST): Explorer Enric Sala found himself in the southern tip of Argentina, on a remote island called Isla de los Estados. It’s been off-limits to tourism since 1923, when it was set aside as a reserve for fur seals. It’s home to a forest of twisting southern beech trees and two of the largest known rockhopper penguin colonies in Argentina.

SALA: And we see these dozens of penguins coming onto the shore. And they were not just swimming, they were jumping and zigzagging and wow! And this is a behavior that we’ve seen in other places where animals are trying to escape from killer whales, from orcas. Wow, is there an orca here? Right. And no orcas to be seen.

And then in front of me, this big brown head comes out of the water, grabs a penguin, and takes it down. That was a bull sea lion. A huge sea lion with a huge head. He was there underwater, waiting, and when the penguins swam over him, he just snatched one and disappeared.

BRIGGS: I’m Amy Briggs, executive editor of National Geographic History magazine, and you’re listening to Overheard, a show where we eavesdrop on the wild conversations we have at Nat Geo, and follow them to the edges of our big, weird, beautiful world.

This week, I sit down with Enric Sala, founder of National Geographic’s Pristine Seas, a project that combines exploration, research, and media to inspire countries to protect the last wild places in the ocean. We’ll hear about some of his coolest expeditions and find out what we need to do to keep the ocean pristine.

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SALA: I am Enric Sala, National Geographic Explorer-in-Residence, and for a living I work to create big protected areas in the ocean, national parks in the sea.

BRIGGS: Enric is the founder and leader of National Geographic’s Pristine Seas project, which leads worldwide expeditions to explore the ocean and supports the creation of marine protected areas, or MPAs for short. Since 2008, Pristine Seas has helped to establish 26 marine preserves with a combined area of 6.5 million square kilometers of ocean—more than twice the size of India.

BRIGGS (to Sala): So when did you learn how to dive, and what inspired your interest in the ocean?

SALA: I grew up on the Mediterranean coast of Spain, in the Costa Brava, in Catalonia. And I was very lucky, because the summers I spent on the shore, on the beach, with my mom and my brother. My father worked at the restaurant during the summer. So I spent my days on the beach, basically. But then on Sunday evening, the entire family was glued to the TV set, watching The Undersea World of Jacques Cousteau. That was my inspiration. You know, when I was a kid, I wanted to be a diver in Cousteau’s boat, in the famous Calypso. This is when my passion for the ocean started.

BRIGGS: Did you start wearing a red beanie as a teenager or…

SALA: No, but I had a Speedo, of course.


BRIGGS: So we did this episode, this podcast episode for Sharkfest about people’s fear of sharks. And I just talked to you a little bit before about one of your early presentations that I saw at Nat Geo where the sharks were everywhere, but you seem pretty relaxed swimming with them. Were you always so relaxed around the top predators?

SALA: When I was a kid and watched the film Jaws, I was terrified of sharks. And then I started diving with sharks. And then we started going to pristine places, which are full of sharks. And the more I dove with sharks, the less worried I was. More people kill themselves every year taking selfies than people being killed by sharks. So I'm not … I’m more worried about the iPhone than about sharks.

BRIGGS: I’m an amateur diver myself. And I remember the first time I was in the water with one and had the same sort of like…(Gasps)… feeling and just this, like, respect for how big and powerful and graceful. But then they seemed so completely uninterested in people.

SALA: Totally.

BRIGGS: Yeah, they were on the reef. They were swimming. They would occasionally kind of like side-eye you, but then keep going. The things that scared me were barracuda. They’re creepy. I don’t know if it’s just the big teeth, but they tend to swim in my blind spot so I can’t really see them. And then I turn around and they’re there and ah. So, anyway.

So you mentioned that you had started diving around the time you were finishing up your Ph.D. So you’re doing Pristine Seas now. How did you decide to make the transition from academia and launch Pristine Seas?

SALA: Yeah. Well, in my previous life, I was a professor of marine ecology at Scripps Institution of Oceanography in La Jolla in California. And my job was to teach and conduct research. And my research was on the impacts of humans in the ocean—the impacts of fishing and global warming mostly. And every new paper had more data and more precision, and we were more confident that, yes, we are killing marine life everywhere. And one day I realized that all I was doing was writing the obituary of the ocean. Actually, rewriting it with more and more precision. And I thought, well, I don’t want to look back 20 years from now and see that all I have done is refine the obituary of the ocean. I felt like the doctor who’s telling you how you’re going to die, with excruciating detail but not offering a cure. You may want to change doctors, right? So this is what I did. I left academia to work on the cure. To work on conservation of ocean life full-time.

BRIGGS: So, what would you say is the most immediate threat to the ocean? You know, is it climate change? Is it overfishing? Is it microplastics? Like, what are the, what’s the biggest one, or most immediate?

SALA: All of them, actually. Historically, the biggest threat has been overfishing. We’ve taken fish out of the water faster than they can reproduce, and overfishing continues. But now we have ocean warming and acidification, which is killing coral reefs and other marine life around the world. And the plastic pollution is very conspicuous, but also we have pollution that we cannot see, like heavy metals, for example. So it’s the three of them. Pollution, global warming, and overfishing, which is killing the ocean faster and faster than ever.

BRIGGS: And I know we’re talking about those as like very, very big things that make impacts. But I know, I think it was Pitcairn Island, this remote island you went to that only has about 50 people living on it, and you saw, like, degraded ocean environments there. I mean, if it only takes 50 people to degrade an area, I mean, how can we protect the ocean?

SALA: Well, we can protect the ocean by not killing marine life everywhere. Right. Something I don’t want this, I wouldn’t like this discussion to be doom and gloom so people will go and listen to fun music. There are good news. The good news is that if we protect areas of the ocean—if we set aside areas without fishing, without mining, without drilling, without destruction of the coast—these areas come back spectacularly. I've seen it with my own eyes all around the world. The ocean has an extraordinary ability to bounce back.

And we know that when you have more fish in these protected areas, now the fish are also larger because we don’t kill them, they take a longer time to die, they reach their maximum sizes. And we know that the biggest females are the ones that produce most eggs in the fish populations that are going to help replenish the areas around these protected areas, these marine reserves. So if we set aside at least 30 percent of the ocean in no-take areas, this 30 percent will help regenerate, will help replenish, the other 70 percent. So we’ll have food for everybody into the future.

BRIGGS: So how do you identify candidates to become an MPA? Does it need to start out pristine and you preserve it? Or is it like you were saying, if you create these things, places can bounce back? Walk me through the process.

SALA: So we have places that are, in the ocean we have this spectrum that goes from totally pristine, remote, uninhabited islands that are not fished, all the way to completely degraded, areas that are like underwater barrens, and everything in between. So we need to protect those places that are left, that are still pristine. We need to save them. But also, we need to protect as many places that are degraded so they can restore themselves and they can get closer to pristine and help to regenerate the rest of the ocean. And in terms of the areas that we target with our National Geographic Pristine Seas project—The last four years we spent a lot of time with a group of over 20 scientists and economists to identify which areas in the ocean are the top priority. What are the areas that, if fully protected, would preserve marine life and all the benefits it provides to humanity? And when you look at those maps, the priorities are basically spread all over the world.

BRIGGS: And it’s interesting because, in my own mind, I think of some of the more tropical places that have coral reefs being, I don’t want to say, like, maybe the more popular or the more well known, but what about like some cold-water environments? What are the things we’re protecting where there aren’t beautiful tropical fish and coral reefs?

SALA: Well, there are beautiful kelp forests in southern Chile and Argentina, for example. And diving in these kelp forests, which you also can find in California and Oregon, is like flying through a tropical forest. You have this brown seaweed that go from the bottom all the way to the surface, forming a canopy through which the light penetrates like stained glass in a cathedral. And they are full of starfish and little invertebrates. And in California, you have all these big fish like black sea bass and sheephead and these beautiful orange garibaldi fish, which is the state fish of California by the way. Every country in the world has areas that are top priority for protection, which means that every country has a responsibility to do something about it.

BRIGGS: So how much, you were saying, you know, 30 percent is sort of what we’re looking at. How much of the ocean is currently part of an MPA or is currently protected?

SALA: That's the problem, that today less than 8 percent of the ocean is under some kind of protection, and less than 3 percent is in no-take areas that ban fishing and other damaging activities. So we need to basically quadruple the amount of ocean that is protected by 2030, so we have eight years left.

BRIGGS: There’s still a long way to go towards protecting 30 percent of the ocean as Enric has suggested, but there’s been a number of recent wins. In March and April of this year, Pristine Seas led an expedition in the waters near Colombia, and in June, Colombian president Iván Duque Márquez announced three new marine protected areas, which will get Colombian waters over the 30 percent threshold. And Pristine Seas was just awarded a $20 million grant from the Bezos Earth Fund. Still, there is a long way to go, so Enric and Pristine Seas will be busy.

Enric’s team sent us some audio from his travels, and listening to these clips is probably the closest I’ll get to setting sail with Pristine Seas. They run into all kinds of amazing animals on these expeditions. Like sea lions…

SALA (on tape): Wow, we were diving in the middle of the kelp forest, and then 20, 25 sea lions came in and started swimming around us like crazy. Spectacular. One of the most playful groups of sea lions I’ve ever seen. Spectacular. The male is growling, saying don’t get too close to my females, I guess.

BRIGGS: So I want to talk to you a little bit about your job job, about what’s a Pristine Seas expedition, and how you get ready for one. Can you sort of walk me through? What do you do when you decide to go on an expedition?

SALA: So let’s say we decide to go to some remote islands in the middle of the Pacific. First thing we need to do is to identify who our local partners are going to be. We always work to support local conservation efforts. Then we need to find a vessel. And the good thing is that now we have chartered a vessel, the Argo, exploration vessel Argo, which is going to be our home for the next five years, starting in 2023. This is going to be our Calypso.

And usually a day in the expedition is: We wake up at six, seven, depending on where we are in the world, have breakfast, prepare, one or two dives in the morning. Come back, enter data. Have lunch, maybe a little nap, and then go diving again. And then basically, usually before 10, we collapse in bed absolutely exhausted, and day two repeat, day three repeat, for weeks at a time. And it’s exhausting, but it is so fulfilling to go to bed knowing that we’ve experienced such a wonderful place and that we have got so much done.

BRIGGS: Especially too if it’s a place that hasn't been well studied. I mean, you’re definitely pioneers.

SALA: Oh, these are the best. These are the best because we don’t know what we’re going to find. That’s the pure exploration.

BRIGGS: What’s been the most surprising thing you’ve found in a region like that?

SALA: Well, I would say the first time we went to a pristine coral reef and jumped in the water—on the Line Islands in the middle of the Pacific and jumped in the water—and saw that, wow, as soon as the bubbles cleared, we were surrounded by sharks. And after counting the number and the size of the sharks and the fish, we realized that if you put all of the fish together and weigh them, the top predators, the sharks, they weigh more than all of the prey together. This would be like going to the African savanna and finding more lions than zebras and wildebeest.

BRIGGS: Wow. So that must have just sort of upended everything we thought we knew about what a healthy reef looked like.

SALA: Oh, absolutely. Because most of the studies on coral reefs have been done on reefs that are easy to access, which means if you can get to [them] easily, people can get to [them] easily. So these reefs have been overfished, overexploited, polluted, degraded over time. So our view of coral reefs was really biased. So we came out of that first expedition basically ripping entire chapters of marine ecology books.

BRIGGS: Are there any other examples that leap to mind of how, basically, other chapters that have been ripped out based on the work that Pristine Seas is doing?

SALA: Well, one thing that we found that wasn’t trivial is that that pattern that we found on the Line Islands was repeated everywhere else where there was no fishing. Right, so that was not a one-off. But something else that we found, also in the Line Islands, is that fully protected areas can help us buy time in this era of climate change.

And that means that reefs that are fully protected, they are more resilient, they are more likely to bounce back after a warming event. And the first expedition we did with Pristine Seas in 2009, we went to the southern Line Islands, in the South Pacific, and these were the most pristine reefs we’ve ever seen. Fish abundance off the charts, and the corals were spectacular. Eighty percent of the bottom was covered by live coral. The government of Kiribati protected this place a few years later, and we thought, Wow, this place is safe forever. But then, in 2016, a calamity happened. 2016, there was the strongest warming event, an El Niño event, the strongest ever measured. And half of the corals died over that summer.

BRIGGS: Oh, wow.

SALA: Half of the corals in the most pristine coral reefs on the planet. We thought, Wow, is there hope for coral reefs if even the most pristine reefs are suffering so much? We decided to give that place some time,and we returned last year. Five years after that warming event. And I was terrified. I didn’t know if the corals would still be dead or if there would be some sign of recovery. And my buddies were getting ready on the inflatable boat, and I couldn’t wait. I just jumped in the water, and I couldn’t believe it. The reef was back. It had fully recovered, 100 percent. Like, wow, was there ever any bleaching here? Was there ever any coral death? And the reef came back because the fish were there.

Because there are these big parrot fish, schools of hundreds of surgeonfish. And these are fish that graze all the time, nonstop. They munch, they gobble all the little seaweed that try to grow on top of the dead coral skeletons, so they keep the reef clean and allow the corals to come back.

BRIGGS: Parrot fish are my favorite. I love when you’re in the water, like you can hear them. That shhh-shhh-shhh noise.

SALA: Yeah. That’s a good sign.

BRIGGS: Yeah, they’re, I mean, they’re cute too.

BRIGGS: Enric’s production team sent us some footage from his expeditions, and, wow, has he seen a lot. Like, unicorn-like narwhals with their distinctive clicks.

(Clicking of narwhals)

BRIGGS: And Enric’s gone from tropical coral reefs…

SALA (on tape): The coral formations with these spurs and grooves and canyons and coral pillars and plain corals forming terraces everywhere, it’s so absolutely gorgeous.

BRIGGS: …to swimming in Arctic waters.

SALA: You know, in this case, when we were in the Russian Arctic, the northernmost archipelago on Earth, the water temperature was minus 1 degree Celsius. It was below freezing. It doesn’t freeze because seawater has so much salt that it freezes at lower temperatures. But it was literally freezing, and that was in the summer.

SALA (on tape): We just finished our dive at Cape Fligely, the northernmost point of Franz Josef Land. And this is as north as it gets. Whoo. My lips, I cannot feel my lips or my fingertips now.

BRIGGS: During the interview, I also asked Enric to show me a couple of his photos and explain the story behind them. And in one of them is this big black fish, with a wide, frowning mouth that kind of makes it look like a grumpy old man. It’s a Mediterranean dusky grouper, and behind him is a colorful backdrop of orange, blue, and yellow coral. Enric says this grouper was about three feet long, which seems pretty big to me as an amateur diver, but Enric says that’s a pretty typical size in pristine areas. According to him, they can grow up to four feet long.

SALA: And the girth, because then they become—at one point they don't grow more in length but they become really fat. That's why they produce so many more eggs, right? Because their volume increases through the power of the cube.

BRIGGS: Because these groupers grow in height, width, and depth, they’ve got a lot more space inside to house their eggs. And not only do these groupers get huge but they also reproduce in an interesting way.

SALA: When it’s time to reproduce, these males display this flashy, spectacular color pattern to say, Hey, I'm ready, this is my territory. So they chase each other out of their territories. And then the females go around looking for suitable males. And when a female decides that, Oh, this is a good one, then they start at kind of a courtship, and they start swimming up towards the surface, and they get closer and closer, cheek to cheek, and start swimming up, spiraling. And sometimes you have other males trying to sneak in, and when they reach their climax, they split, and you can see they release sperm and eggs. So you see this white cloud, and they go back to the bottom. In other places, groupers reproduce, not in pairs like this, but you have 3,000, 4,000 groupers, males and females all together, and they form this ball, and same thing. They swim up to the surface, and they release these clouds of milk, of sperm and eggs. And that’s the way they reproduce. Spectacular, but it’s all external reproduction.

BRIGGS: So what can the average person listening to this podcast, what can they do to protect the ocean?

SALA: There are so many things that people could do. The worst thing we can do is to give people a laundry list, basically, because people feel overwhelmed. But there is something that people can do every day that helps not only the ocean but also helps the land and the climate, which is, eat less animals and more plants.

That means that if we ate more plants, if we had a flexitarian diet, if not a vegetarian diet, we still would get all the proteins and nutrients that our body needs. It would be better for our health. We wouldn’t require so much land. Because today in the United States, for example, 41 percent of the land is used to grow livestock. Forty-one percent of it. We don’t need to eat all that red meat.

So if we had a flexitarian diet, we would require only half of the surface of the land to produce our food. That other half that is now mostly degraded, industrial, agriculture, we will be able to give back to nature. So nature will be able to give us all many more benefits in exchange. And also, livestock produces a huge amount of greenhouse gases. They are a significant contributor to climate change as well. So eating more plants and less animals would be good for our health, for the environment, and for our climate.

BRIGGS: If you like what you hear and want to support more content like this, please rate and review us in your podcast app, and please consider a National Geographic subscription. That’s the best way to support Overheard. Go to natgeo.com/exploremore to subscribe. 

Learn more about the recovery of the coral reefs around the southern Line Islands in November’s National Geographic magazine. There’ll be an in-depth article written by Enric, with some gorgeous photographs of this pristine ecosystem. And the article will be available on the website in mid-October.

Learn more about the work of Pristine Seas on their website. Just search for Pristine Seas on natgeo.com.

That’s all in the show notes, right there in your podcast app.


This week’s Overheard episode is produced by Khari Douglas.

Our producers include Ilana Strauss.

Our senior producers are Brian Gutierrez and Jacob Pinter.

Our senior editor is Eli Chen.

Our manager of audio is Carla Wills.

Our executive producer of audio is Davar Ardalan.

Our photo editor is Julie Hau.

Hansdale Hsu sound-designed this episode and composed our theme music.

This podcast is a production of National Geographic Partners.

The National Geographic Society, committed to illuminating and protecting the wonder of our world, funds the work of National Geographic Explorer in Residence Enric Sala.

Whitney Johnson is the director of visuals and immersive experiences.

Nathan Lump is National Geographic’s editor in chief.

And I’m your host, Amy Briggs. Thanks for listening, and see ya next time.


Want more?

Learn more about the work of Pristine Seas on their website.

Learn more about the recovery of the coral reefs around the southern Line Islands in November’s National Geographic magazine. There will be an in-depth article written by Enric, with some gorgeous photographs of this pristine ecosystem. The article is also available online here

Also explore:

Dive deeper with two other Overheard episodes about the ocean:

In “The Secret Culture of Killer Whales,” photographer Brian Skerry swims with killer whales and discovers these apex predators have unique cultures that aren’t that different from our own.

In “The Gateway to Secret Underwater Worlds,” discover how Jacques Cousteau opened up the deep sea to humanity and left a legacy that continues to drive underwater exploration today.