Enric Sala: We have taken fish out of the ocean faster than they can reproduce. We have now hundreds of studies from hundreds of reserves showing that when you protect the place from fishing, the fish come back. When you don't kill fish, they take a longer time to die. They grow larger, they reproduce a lot, and some of these fish spill over the boundaries of these reserves, helping the fishermen around.

I grew up on the Mediterranean coast of Spain and as a kid I couldn't wait to see the underwater adventures of Jacques Cousteau and other people. And I tried to emulate the adventures with my... So, my younger brother and I explored the very shallows of the Costa Brava, off the northern Mediterranean coast of Spain, and, you know, Cousteau showed us this incredible places with sharks and whales, sea lions, dolphins, coral reefs, it was extraordinary. But when I went to the Mediterranean, when I went swimming in the Mediterranean, this is what I saw. It was empty. There are four fish there, which were smaller than the little mask I used for snorkeling. And I was confused, I thought, “Well, you know maybe the Mediterranean is...it's empty, it's like this, you know. And this richness that Cousteau showed us is something that belongs to exotic locations.” But then as I...grew older and I studied marine biology, I learned that what happened to the Mediterranean, happened everywhere because we have taken fish out of the ocean faster than they can reproduce. Ninety percent of the large fish, like the tuna and the sharks, are gone. And we killed them in the last 100 years alone. Right now about a third of the fisheries of the world have collapsed. If we continue like this, before 2080 most of the fisheries of the world will have collapsed. Not only do we take fish out of the ocean faster than they can reproduce, but, also, we are doing it in a very destructive way. These are trawlers, shrimp trawlers, in the South China Sea. You can see their tracks from a satellite photo. In some places, for every pound of shrimp that is caught, ten pounds of other animals, including fish, starfish or corals, are killed and discarded overboard. And on top of that, we have pollution, and now, every year, eight million tons of plastic enters the ocean. And on top of that we have climate change, global warming, which is making the ocean warmer and more acidic, which is killing coral reefs everywhere. This used to be a coral reef now this is a ghost of a coral reef, dead broken coral overgrown by seaweed and slime.

So, imagine, I was a professor at the University of California in San Diego. I studied the impacts of humans in the ocean. The impacts of fishing, pollution and climate change on ocean life. And one day I realized that what I was doing was simply writing the obituary of ocean life. And I felt really, really frustrated. I felt like the doctor who's telling the patient how she's going to die, with excruciating detail, but not offering a cure. And that day, I decided that I was going to quit academia and spend my full-- my whole life working on conservation. Trying to bring some of that richness of the ocean back.

So, in 2008, I moved to Washington, and we started by asking questions. And the main question was: Are there pristine places left in the ocean? So, we found this place in the middle of the Pacific Ocean. The Line Islands. Eleven islands that cross the equator. Some belong to the US, some belong to the Republic of Kiribati. Seven of these islands are uninhabited. So, we thought, “Well, uninhabited in the middle of the Pacific Ocean. A Google search doesn't reveal much scientific information about these places. They are probably pristine.” They are as close to pristine as possible, we thought. So, we put together this rag tag team of scientists and filmmakers. We got on this boat, departing from Tahiti and off we went for five weeks to places like this. Millennium Atoll. This is the size of Manhattan, that belongs to Kiribati.

So imagine, we go to a place where we had no scientific information. There were no films about this place before. There were no underwater pictures of these places. So, we felt like real explorers. We get in the water, and as soon as we jump in the water, this is what we see. You know, compare this to that dead coral reef that we saw before. Not only we saw healthy reefs, but lots of predators. Lots of predators. You know, you jump in the water and as soon as your bubbles clear, you are surrounded by 10-12 sharks. If you go to the African plains, to the Serengeti, you would expect to see hundreds of thousands of wildebeest, and zebras, and antelopes, and all the animals that eat the grass. The herbivores. And then just a few thousand or a few hundred lions, right? This is what we thought would happen on the reef. This is what we learned in school. This is what we found in textbooks. But when we went to a pristine reef for the first time, we discovered then what we thought was natural was not. That biomass pyramid is upside down. You go to one of these pristine reefs and more than half of most of the biomass, more than half of the biomass of fish, is accounted for by the top predators. The big guys on top of the food chain. This would be like going to the Serengeti and seeing more than one lion per every wildebeest. That was our first big, big discovery. And, you know, we went to these uninhabited reefs and we saw these wonderful things. But then we went to a reef with 5,000 people nearby and this is what we saw. Dead coral, no fish. Only 5,000 people were able to do this.

So, our first question was: Are there pristine reefs out there? Check, yes. Now, the question now is: How many people are enough to turn something pristine into something that is not? Five thousand people alone are able to turn a pristine coral reef into this. So, we decided to go to a place with less people and test that question. So, we went to the most extreme place. Pitcairn Island. Fifty-two people live on Pitcairn Island. There are four islands. It belongs to the UK. It's an overseas territory of the United Kingdom. Pitcairn is inhabited by 52 people. The other three islands are uninhabited. So, also we had the perfect experimental situation, right. One island with people, three islands nearby without people. So we could test our question. Would 52 people be enough to eliminate the big predators in the water, to turn something pristine into something that is not? This is Adamstown, the only settlement and this is the only territory in the world where I know all of the inhabitants. We met all 52 of them, including kids. We jump in the water and... the visibility was extraordinary. So, we could see our diving buddies 75 meters away. More than 220 feet away. The most crystal clear water we've seen anywhere in the world. You see the corals cover the entire bottom but there are no fish. Fifty-two people, there were some fish but no sharks, no groupers, no snappers. And then, we had to do it. We had to go to these pristine places without people and see what we find. So, we went to places like this. Henderson Atoll. And we jump in the water and the coral reefs were really, really, really healthy. Spectacular, some of the most beautiful... reefs like this, reef formed by just one species of coral that look like... like giant roses. And our friends. Look at all these scratches, these guys are really... They are like stray cats. They are really, really curious and rowdy. And of course, lots of sharks. The same thing we found on the Line Islands we found here. This inverted biomass pyramid. The place where the predators dominate. So, there you go, that was our question answered. Even 52 people, a population as small as 52, are able, over time, using just traditional fishing methods are enough to turn something pristine into something that is not. The corals were fine, they didn't have the impact that the 5,000 Polynesians had on that reef, but they were able to remove, over time, all these large fish that previously inhabited the reef. That's what we do. Not only we go to these places but we come back to these places. So, we come back and we show them what we found. And, in most cases, they had no idea of the natural riches that they had. And then we work with the local communities to try to inspire their governments to... to protect the environment around them. And our goal is to inspire leaders to protect these places. And we've been to 15 of these places with our partners, and eight have been already protected... in some of the largest marine reserves in the world, covering an area of three million square kilometers. That's the size of Alaska, California, Texas, Montana, and New Mexico together. And half of the ocean that has been fully protected in history, has been protected in the last 13 months.

We have now hundreds of studies from hundreds of reserves showing that when you protect the place from fishing the fish come back. The size of fish increases by a third, compared to nearby unprotected areas. And the biomass of fish, the measure of tons of fish per square kilometer, increases by 446 percent. It also happens that these reserves produce so many fish, you know. It is something very simple. When you don't kill fish, they take a longer time to die. They grow larger, they reproduce a lot, and some of these fish spill over the boundaries of these reserves, helping the fishermen around. And in places like the... marine reserve in Mombasa in Southern Kenya, the fishermen have doubled their income, just because they are fishing around a marine reserve. So, imagine. The reserves help to restore fish inside their boundaries, they help the fishermen around, but, also, they bring tourism. When the dive-- When the fish come back, the divers come in. The biggest example is the Great Barrier Reef, which is this huge marine park a third of which is fully protected. That provides 56,000 jobs... and about five billion Australian dollars, three and half billion US dollars, to the Australian economy. And the value of tourism is 40 times the value of fishing. So, these places are a win-win-win. Now, think of the ocean that is not protected... as a bank account where everybody withdraws, but nobody makes a deposit. And you don't need to be an economist to know what's going to happen to the bank account. These marine reserves that are fully protected are savings accounts, with the principal set aside that produces compound interest. Produces interest that we can enjoy.

Right now between one-two percent of the ocean is fully protected. And scientific studies recommend that at least 20 percent of the ocean should be protected. Some studies even claim that 50 percent should be protected. So, we have a long, long way to go. But, you know, we are determined. We've been doing this for seven years and we want to do it for three more years and go to 12 more places. Some people say, “Oh, they are so far away. If you bring them to the light people are going to discover them and the bad guys are going to go there and ruin them.” Well, if I was able to find these pristine places with a National Geographic atlas and Google, you know, so can the bad guys. And in some of these pristine places, we've seen sharks with hooks in their mouths. There is some illegal fishing already threatening these areas. So we need to save them before it's too late. These places are the only base lines we have left of what was natural in the ocean. But most important, they can help us determine... what future ocean we want. You want an ocean that is empty and full of plastic, or an ocean that is full of life... and can continue providing for us? Thank you so very much.