The swarm of jack mackerel looks like a silver wall in front of the divers. Bright sunlight breaks through the water surface and makes the fishes' scales shimmer like an artfully forged mirror. As if following an invisible sign, the animals abruptly turn and fly up before quickly returning, as one undulating mass.
Sylvia Earle, 80, glides slowly past the bodies, an underwater camera in her hand. The photo yield has been plentiful today, on the reef at Cabo Pulmo, a small coastal town on the southern end of Mexico's Baja California peninsula. The tiny village on the Sea of Cortez had once been a normal fishing village. The reef provided a decent income for a handful of families, but then the wealth of fish spread by word of mouth.
First came the recreational fishermen, then the trawlers with their longlines and nets. By 1980, the reef had been fished bare. After pressure from locals, Cabo Pulmo was declared a national park. Since then, fishing has been banned here. In the last three decades, the biomass of fish has more than quadrupled. And the people are earning good money from ecotourism.
That's why Earle has selected Cabo Pulmo as a "Hope Spot." She has identified about 200 of these kinds of locations through her foundation, Mission Blue. Together with the International Union for the Conservation of Nature (IUCN), she is working on a global action plan for marine reserves. In an interview, she explains why the ocean is so important for life on earth.
SPIEGEL: What is it that's so special about Cabo Pulmo?
Earle: Cabo Pulmo is a small place, but it is making a big difference in terms of inspiring hope. This village shows that if you make an investment, care for a place, it can recover. The fish had been depleted, the coral reefs were in trouble, but by taking the pressure off, by creating a safe place in the ocean for the wildlife that is here, recovery has taken place. The people took their ocean back, replaced the fishing with ecotourism, and the community is thriving. What I love about this place is the idea that you can use the ocean without using it up. People here show us that the best way to ensure continued prosperity is through sustainable use. The living ocean is their bank, their treasure, their hope.
SPIEGEL: What is the current situation in the Earth's oceans? What kind of crisis are we facing?
Earle: Since I began exploring the ocean in the 1950s, 90 percent of the big fish have been stripped away. Tuna, sharks, swordfish, cod, halibut, you name it, the numbers have just collapsed. Also, about half of the coral reefs are gone, globally, from where they were just a few decades ago. We have found ways to capture, kill and market ocean wildlife on an unprecedented scale. It's an absolute catastrophe. The ocean seemed like a sea of Eden. But now we are facing paradise lost.
SPIEGEL: Aren't you exaggerating? After all, the ocean seems to be endless.
Earle: We humans have this idea that the ocean is so big, so vast, so resilient that it doesn't matter what we do to it. That may have been true 1,000 years ago. But in the last 100, especially the last 50 years, we have destroyed the assets that make our lives possible. I am haunted by tomorrow's children asking why we didn't do something on our watch to save sharks, bluefin tuna, squids and coral reefs -- while there was still time. We are depleting this immense diversity and abundance of life, and it matters tremendously for the future of the planet.
SPIEGEL: Why is that?
Earle: Life in the ocean makes Earth hospitable. We are sailing along in the universe and we have a blue engine that is making everything alright. The ocean governs the climate and the weather, it is taking care of the temperature and it is shaping the chemistry of our planet. The oxygen cycle, the nitrogen cycle, the carbon cycle, the water cycle -- all of these are linked to the existence of life in the sea. The Earth is a tiny blue speck in a universe of unfriendly options. And the ocean is our life support system. No blue, no green. It's really a miracle that we have got a place that works in our favor. And if you think the ocean isn't important, imagine Earth without it.
SPIEGEL: Mars comes to mind .
Earle: Indeed. There was a movie recently, "The Martian," that says it all. You can survive, but what kind of life is that? We are blessed with a place that is open to the universe and, despite this, supports this very thin envelope of air we call atmosphere, which holds just the right amount of oxygen for us to breathe. Our job is to keep what is working intact and not destroy what we have got. In the past few decades, Earth's natural systems have endured more pressure than in all preceding human history. What we put into the atmosphere in terms of burning fuel is unprecedented. We are not only warming the ocean and the planet as a whole, but we are also acidifying the ocean and changing its chemistry. The ocean is dying, and we have no place to escape to if this experiment doesn't go in our favor.
SPIEGEL: You spend 300 days a year traveling as kind of an ambassador for the ocean. What drives you?
Earle: If I seem like a radical it's because I have seen things that others have not. I am driven by what I know; that the world I love is in trouble. I've spent thousands of hours under water. And even in the deepest dive I have ever made, 2.5 miles (about 4 kilometers) down, I saw trash and other tangible evidence of our presence. When I was 12, we moved from New Jersey to Florida. The Gulf of Mexico was literally my backyard. Every day, I could see the ocean. At low tide I went out and played in seagrass meadows that used to come right up to the shore, filled with tiny seahorses, pipefish and soft corals. There was so much life! But then I witnessed the change, the loss of the shoreline, the loss of the mangrove trees, the loss of the seagrass meadows. Shallow bay areas were turned into parking lots. People call that reclamation, but it is the transformation of a healthy living system into something that is barren and dead.
SPIEGEL: What do you suggest doing to help the ocean?
Earle: When you are a child you learn your alphabet, your numbers, but increasingly, we must learn from the earliest stages that the highest priority has to be to maintain the world as a safe place for humankind. Fortunately, we know more about the problems that we have than in all preceding history. We know now the consequences of the things that we put into the air, into the water -- of the way we treat life on Earth. We understand that we must make peace with nature -- that our lives depend on it. With knowing comes caring. The next 10 years could be the most important in the next 10,000. It is not too late to turn things around. We still have 10 percent of the sharks. We still have half of the coral reefs. However, if we wait another 50 years, opportunities might well be gone.
SPIEGEL: Your foundation supports the designation and protection of so called "Hope Spots" around the world. What are you aiming for?
Earle: There are now more than 4,000 places in the sea around the world that have some kind of protection. The bad news: You have to look hard to find them. What you find instead is destructive fishing, mining, gas and oil exploration. Only two percent of the ocean is fully protected right now. We believe that this area has to increase at least tenfold by 2020. That's why we look globally for places that are in great shape, pristine areas that, if protected, can serve as a source of renewal. We have about 200 places already nominated as Hope Spots. Hope Spots encourage people to take the initiative, to take action on a community level.
SPIEGEL: Most people, however, feel powerless. What can each one of us do individually?
Earle: Everybody can make choices that will make peace with the natural world. You can choose not to eat tuna, not to eat swordfish, not even to eat the little herring. Eating wildlife is probably not the smartest thing that we can do in terms of maintaining the integrity of natural systems. Fish from all over the world, from deep in the sea, wind up in countries from Germany to Japan. That is just crazy. We are taking way more out of the ocean than the ocean can replenish. You should ask where your food is coming from. You should know what is taken out of the ecosystem in order to give you a moment's sustenance. Give the ocean a break. Give yourself a break. If you make the choice to just go with the flow, that is a choice to make a difference in a negative way.
SPIEGEL: What gives you hope?
Earle: Places like Cabo Pulmo do. Imagine taking the miracle that happened here and spreading hope around the world so people change the way they think about respecting nature, treating all creatures, including one another, with dignity and understanding. You can do that too, in your own life, in your community, in your country and internationally. With care and protection, with safe havens in the ocean, there is still a good chance that we can turn things around. We don't have to be that greedy generation that just continued to take down the underpinnings of what makes the planet work in our favor. Use your power to do whatever it takes to secure for humankind an enduring place on this little blue speck in the universe -- our only hope.
Sylvia Earle, born in 1935, took part in one of the very first marine research expeditions in the Indian Ocean in 1964. In 1979, she set foot on the ocean floor near Hawaii, encased in a steel diving suit, the legendary Jim Suit. Soon after, she descended to a depth of 1,000 meters on board the Deep Rover, one of the world's first deep-sea submarines. Earle later became a scientist at the US National Oceanic and Atmospheric Administration. Today, she travels around the world 300 days a year as an ambassador for the ocean.