Earth & Sky

Our oceans, ourselves

Deep sea explorer Sylvia Earle on our blue planet.

Sylvia Earle is the perhaps the most renowned ocean explorer in history.

Dr. Earle has pioneered research on marine ecosystems and has led more than 50 expeditions totaling more than 6,000 hours underwater. In 1979 she walked untethered on the sea floor at a lower depth than any other human being, before or since. In 2005, Earle celebrated her 70th birthday swimming with sharks near the Yucatan fishing village of Holbox.

She spoke with Earth & Sky’s Jorge Salazar about the interrelationship between humans and Earth’s oceans.

Salazar: Why are Earth’s oceans so important for people?

Earle: The ocean is our life–support system. It’s the source of most of the oxygen in the atmosphere. With every breath we take, we should be grateful that there is an ocean out there. For every drop of water that we consume, we should be grateful that there is an ocean out there, because 97% of Earth’s water is in the ocean. What falls on the land and sea as rain, and sleet and snow, ultimately originates, largely, out there in the sea. So, if we want to take care of ourselves, we need to start by taking care of the ocean.

Salazar: You’ve spent a great deal of your life studying the oceans. What are some of the changes you’ve seen in that time?

Earle: In my lifetime, since the time that I was a little girl living along the shores of the Gulf of Mexico, I personally have witnessed the decline of coral reefs, of sea grass meadows, of the kinds of systems that really lend a good health to the ocean. I’ve also seen the disappearance of many things that once were common – things such as nassau groupers, pink conch, and a lot of small creatures that once abounded in near shore waters that are simply gone. These are not signs of good health.

In fact, we’ve seen in 50 years, the loss or serious decline of half the coral reefs around the world.

We’ve seen the loss of 90% of the big fish – they’re simply gone – in 50 years, as a direct consequence of both how many we’re taking, and the destructive techniques that disrupt the places that fish require to recover. Not just fish, but shrimp and lobster and the whole suite of organisms that we tend to like to eat.

Now, that doesn’t mean that we can’t figure out ways to basically have our fish and eat them too. But we’re not doing it now. We need to be much more assertive about protecting broad areas of the ocean that fish and other marine life require, that the ocean itself requires in order to maintain integrity, the health of the systems.

Right now, most of the ocean is up for grabs. It’s being over–fished, it’s being over–polluted, and the consequences are not just a matter of concern if you care about dolphins and whales and things. But, it should be a fundamental concern to everybody on the planet, no matter where they live, because the ocean is the cornerstone of what makes this blue planet function as it does.

Anyone who looks over the shoulders of astronauts considers the world from afar, Those images from space show that this planet is mostly ocean. Without oceans, consider what we would have instead, a planet much like Mars, where people may someday set up housekeeping, but not six billion of us, and not anytime soon. Water is fundamentally the cornerstone, the key. But it’s life in the ocean that drives the way the world works. It generates the oxygen, absorbs carbon dioxide that shapes the chemistry of the planet itself.

Without life in the ocean, Earth would still be a fairly barren place. There was plenty of life a billion years ago, entirely microbial. It’s only in the last half billion years or so that Earth has become hospitable to the likes of us, when enough oxygen was generated to make the planet a place that we can simply enjoy, without special space suits or spacecraft, or habitations that are protected from the outside, whatever it is. Earth owes its existence as we know it, the congenial, healthy, friendly atmosphere, because there is an ocean, and it is filled with life.

But around the coastline of the United States, certainly in the Gulf of Mexico, all around the world, the situation is much the same. Upstream activities are having a downstream consequence, from the tops of mountains, through the coastal waters and into the sea. We are changing the way the ocean functions, and therefore the way the world functions.

Now, it seems like a lot of bad news. But the good news is that we still have a chance, or at least it appears that we do. If we take care now, we can still turn things around. Ninety percent of the big fish are gone, but ten percent are still there. If we give them a chance, give them a break, there’s a good chance that they can recover. If we take steps necessary to recover coral reefs, they may rebound from their current downhill catastrophic decline. There are actions that individuals can take, and there are actions that nations can take. The real key is paying attention to the news that scientists around the world are bringing back, saying we have a problem, all of us have a problem. Now is the time as never before and maybe as never again to make a difference.

Salazar: What are some of the things that scientists are learning about humans’ relationship with the ocean?

Earle: In the last half century, we have learned more about the way the world works – land, air, waters of the world, oceans, freshwater, all of it – and how it relates to us and what we’re doing to it. We’re learning that the fabric of life itself, whether forests, or coral reefs, or the wildlife that lives in places on the land and in the sea, or in the fresh waters of the world, all of these are parts of what makes the world function.

And we’re a part of it. We’re not detached in some isolated way. Although living in cities, living far from the ocean, or far from any wild, natural place, we sometimes lose sight of the fact that we are absolutely and utterly dependent on these natural systems for the most basic things. The oxygen in the atmosphere, every breath we take, originates in plants that are out there on the land or in the sea, more than 70% actually is generated in the ocean. The small plants, and some of the larger ones too, but they’re out there in the ocean, and we just don’t see it. So it’s hard to understand how, when we are disrupting these systems, cutting the forests, or undermining the chemistry of the ocean itself, and thus the way these processes work, that we’re really threatening our own survival, our own well–being. There’s another avenue that has a very direct impact on human beings.

When we consume fish, we are also consuming the things that we have put into the ocean. The phenomenon is known as bioaccumulation, means the things that you really don’t want in you, mercury, lead, the various pesticides and herbicides and other noxious chemicals that we’ve poured onto the land into the air, ultimately going into the sea and into the creatures that live there, that when we consume those creatures, they come back to us in a concentrated form.

Now, some people believe, and it’s true under normal circumstances, that eating a few fish is probably a good thing. But, in today’s world, it’s not such a good thing, given the heavy doses of what they have been taking into their system as a consequence of what we’ve been putting into the ocean, or into the freshwater lakes and streams, that ultimately comes back to us from the creatures that we extract.

But there’s another way of looking at the wildlife in the sea. Many people think of fish only in terms of something to eat, a commodity, rather than the way they think of birds, or the other creatures that we regard as wildlife. But fish are important in terms of maintaining health of the ocean itself. Just as on the land, where we’ve come over a period of years to recognize the importance of lions and tigers and wolves and owls and eagles. We used to think of them as varmints, as something that are really a problem that we should reduce their numbers because they are competing with us. But now, we understand that they’re part of what makes any ecosystem healthy, and their counterparts out there in the ocean, the large fish that we tend to consume, are more than the equivalent of lions and tigers. They’re even further up the food chain, because they eat fish that eat fish that eat fish, and so on, and finally getting to the grazers that eat plants.

But there are many conversions along the way. Sharks, swordfish, groupers, snapper, halibut, whatever the favorite fish of your dreams, swimming with lemon slices and butter. They’re actually more important to human beings, swimming out there in the ocean alive and well, doing their bit and part, maintaining the structure of the ocean, the predator–prey relationships, that in turn shape the chemistry of the ocean, that in turn shapes the chemistry of the planet.

Imagine yourself on a spacecraft. There you are, taking for granted the atmosphere, the nice, comfortable place that you have, and you’re flying along in space. And there’s this part of the population that’s intent on chopping off bits of the wings, and throwing away the nuts and bolts that hold the plane together, or drilling holes in the floor, consuming the very seat that you’re perched on. That’s what we’re doing to the planet; we’re eroding away the very substance of what keeps us alive.

What has really changed our perspective, more than any other single thing, is having people go out there in space and look back on Earth, and to recognize that it is just one system, and it’s very special. In the entire universe, we don’t know of another place that is like the Earth that has all of the features that are comparable to what make this planet hospitable for the human species.

So, we need to take care of this planet, this life support system first. We’re not doing it. Not because we don’t care. It’s largely because we are narrow. It’s a relatively new and stunning concept, that human beings are a part of all the rest. Until very recent times in the history of humankind, we thought that we had to dominate, to conquer the wild places in order for us to survive. We’ve not thought of being able to survive only because we take care of the wild places, the natural systems, in the land, and in the sea, in the lakes and the rivers and the streams. All of this is just crucial to maintaining the way Earth generates the very things that we need, whether it’s freshwater that rainfalls, or it’s basic, benevolent climate that does have swings over time. The climate gets cooler and it gets warmer, ice ages come and ice ages go, but it is somehow maintained within a band that is favorable for the likes of us.

Human beings have been around in some form or another for a million, or two million, or five million years, depending on how you count. But civilization has prospered only in the last few thousand years. Maybe the last ten, but certainly in the last five, and mostly in the last two or three thousand years, we have really begun to develop cities, develop technologies, to develop a way of looking at ourselves in the context of the world as a whole. We’ve begun to look at what makes life possible on this planet, as compared to any other place in the universe.

We are facing a critical juncture in the next decade, probably the most important decade in the next thousand years, for us to take actions that will protect what we can of the land, of the wildlife, of the ocean and the wildlife there, for their sake, of course, but mostly, selfishly, for our sake. It’s the key to human survival, taking care of the natural systems that take care of us.

Salazar: What can people do to make a difference?

Earle: Among things that people can do to make a difference is, first of all, to become informed. The most important thing is to know. You can’t care, you can’t act, if you don’t know. If you just make the effort to become as well informed as possible, then actions will follow.

You’ll see that it’s important to take care of the natural systems that take care of us. During the era of President Theodore Roosevelt and those who followed, especially in the beginning of the 20th century, there was a growing awareness that the land was in trouble unless we took active measure to protect those wild places, the great forests of the West, the Smoky Mountains, ultimately in the East, and other treasure now in our National Park system, nearly 400 special places that protect our national, natural, and cultural and historic heritage. And if specific, positive actions had not been taken years ago, and the actions that are still being taken, to proactively protect what we love, to protect what we know matters to us, it surely would be lost.

If we had taken no action, there would be no national parks, no state parks, no protected areas, no Nature Conservancy or World Wildlife Fund, no Conservation International or other organizations taking these movies around the world. Especially thinking about our own backyard here in North America, what chance would we have of having these special places still as a legacy for ourselves, and for everyone who follows? They’re easy to destroy, and very difficult to put back together again once they’re gone.

Now, in the ocean, there are some promising moves in that direction. In 1972, the United States passed legislation to protect the ocean, actually the first in the world, about at the same time that Australia recognized the need to take actions in the ocean to protect the ocean. The Great Barrier Reef is one example of the actions taken in Australia. In this country, there are presently 13 National Marine Sanctuaries embracing something like 18,000 square miles of coastal waters. It sounds like a lot, and it’s a great beginning, but it’s less than a fraction of one percent of the waters that are under U.S. jurisdiction. We have a long way to go before we could really take a deep breath and say yes, we’ve secured the safety, the integrity of these natural systems that insure the good health of the ocean, and therefore, our good health as well.

That’s one really important thing that people can do: take care of our national parks and do what we can to establish new ones, on the land and in the sea. And that doesn’t mean hands off, or flippers off, or whatever. It means that these are places we can use, enjoy, and love, but just like going into a special place that you love on the land, for example a museum, you don’t break things. You take care of them. You respect them, you use them, you enjoy them, but you don’t destroy them.

That’s what we need to do more of, on the planet everywhere. Not to consume the basic structures, the basic elements of what makes the planet work for us. We need to plant more trees, we need to take care of restoring some of the damaged ocean systems.

As individuals, these are things you can have hand in. You can work with your local governments, your state governments, even kids. As the former chief scientist for NOAA, the National Oceanic and Atmospheric Administration, I know how important letters from children are. They get read, they get passed around, and they get put on bulletin boards. People just think it’s great that kids care. And because they care, those that are in charge of making the policies respond, thinking about the future of those children who will be growing up inheriting, for better or worse, the decisions and consequences of the decisions that are now being made. Children have power.

Of course, grownups have power too. We have the power of making personal choices. Not long ago, before I knew any better, I used to eat fish of all sorts, and crabs and lobsters. I don’t any more. I have far more respect for them alive as important elements of what makes the ocean healthy. I don’t eat songbirds, either, although certainly my predecessors did. Anything on the land used to be fair game. As hunter–gatherers, that’s how we made a living. But it’s not how we make a living today.

Now that doesn’t mean that you can’t go out and get a turkey or a goose or a duck every once in a while, as a hunter gatherer, and it doesn’t mean that you can’t go out and catch a fish every once in a while to feed your family, feed yourself, feed your community. But what’s really harmful right now is the large–scale commercial taking of wildlife from the waters of the world.

Salazar: Looking ahead, what do you see as the future of Earth’s oceans?

Earle: As never before, we have information about the nature of the world, but especially about the ocean. In the last 50 years, we’ve learned things about the ocean that I didn’t even imagine could be possibly true when I was a kid – the fact that there is 40,000 miles of mountain chains that run down the Atlantic, Pacific, and Indian Oceans, like giant backbones. You don’t see them because they’re underwater. So, most people probably aren’t even aware that they’re there. Nobody was, a hundred years ago. But today, if you look at maps that show this configuration of the sea floor, there they are, this magnificent formation that runs all around the planet.

We didn’t know 50 years ago that continents move around. That’s knowledge that’s come about in the last few decades. The existence of entire new communities of life in the deep sea have been discovered only in the last few decades, as has the implications about the generation of energy that drives the way the planet works. There are bacteria and other microbes in the deep sea that do not rely on sunlight, photosynthesis, to generate energy that is passed along through food chains to drive entire ecosystems, most of what we see above water. But, in the ocean, in the deep sea, these chemosynthetic bacteria fix energy from the ambient chemicals, using water of course as a key.

Without water, there is no life at all. So that’s fundamental. But there are other pathways to generating and fixing energy and driving ecosystems that we did not even know existed at all when I was a little girl. Now, people are beginning to explore them, put that information on the balance sheet, understanding more about how the planet works.

So, as never before, we have learned things about the ocean, about the world, and the way it works, and why it matters to all of us. We’ve learned more in the last half century than all of the preceding history put together. At the same time, we’ve lost more, lost more because of what we’re taking out of the ocean, lost more because of what we’re putting into the ocean, causing serious pollution around the coastlines of the world, dead zones that have grown up in the last 50 years that are growing in numbers.

So, in the next 10 years we have a chance to reverse the troublesome trends, we have a chance to really move out and learn, and understand more about, not only how the natural systems work, but how to restore what we’ve already lost. Just as, on the land, you can make a difference by planting trees, so some people are making a difference out in the ocean by restoring and replanting marshes, sea grass beds underwater, and doing what can be done, what we know now how to do, to bring coral reefs back into a state of good health.

Sometimes, just by showing restraint, by no longer taking and killing the large fish, by protecting the turtles, by protecting the manatees, by protecting the sharks and other creatures that are vital to the health and integrity of these systems, just as protecting the special places on land makes a difference in the health of the land.

Salazar: Dr. Earle, it was an honor to speak with you today. Thank you.

Salazar spoke with Dr. Earle in October, 2004.