National Geographic Fellow Enric Sala explains why a healthy reef is a landscape of fear, how our perception of what’s “natural” in marine ecosystems has evolved, and what we can do to restore balance to the seas.
By Ford Cochran
National Geographic hosted a live recording of National Public Radio’s Talk of the Nation at our Washington, D.C. headquarters yesterday. During the program’s first hour, host Neal Conan spoke with journalist Joel Bourne (author of National Geographic magazine’s October 2010 cover story on the Deepwater Horizon disaster), NPR science reporter Richard Harris, and Florida State University oceanographer Ian MacDonald about the fate of spilled oil in the Gulf of Mexico and of the creatures who encounter it. During the second hour, Conan discussed the larger fate of the world’s ocean with two oceanographers and National Geographic explorers, NG Fellow Enric Sala and NG Explorer-in-Residence Sylvia Earle. I interviewed Sala shortly after the program.
Photograph by Becky Hale
Enric, why do you describe healthy reefs as landscapes of fear?
A pristine reef is like a landscape of fear. You have all these big animals–the sharks, the snappers, the groupers, these big mouths. And the smaller fish, the prey of all these predators, are really scared. They are hiding.
It’s the same thing that happened in Yellowstone National Park when the wolves were reintroduced in 1995. Before that the deer were grazing all around, they were destroying the forest little by little. But when the wolves were reintroduced, then fear came to the deer, and the deer are not eating so much. The forests are coming back. So having the predators there is good for the ecosystem, it brings balance to the ecosystem.
Almost no one alive remembers what the ocean used to be like, the virgin healthy ocean. We have totally changed it. Back then, 200 years ago, 500 years ago, the water was clear and full of large fish, large predators like sharks and groupers, snappers, cod. But we have removed 90 percent of these large predators from the ocean in the last century.
Right now, what we have is water that’s not so clear because of all the pollution and all the runoff from land. And most of the fishes are small. We have replaced the large animals with small fish and microbes and jellyfish.
Our impact in the ocean depends on what type of fish we eat. Removing a tuna from the ocean has a larger impact than removing an anchovy, for example, and this is why: At the base of the food chain we have plants that are eaten by small animals, which in turn are eaten by anchovies, which in turn are eaten by larger fish and tuna.
So let’s say that an anchovy requires one hectare per year to survive, one acre per year to survive, and a tuna requires 10,000 anchovies per year to survive. So the footprint of the tuna up in the food chain is much greater than the footprint of the anchovy at the bottom of the food chain. As we go up on the food chain, as we approach the top predators, the greater the footprint is. So we should try to reduce our consumption of the big guys up the food chain. We’re taking too much of the productivity of the ocean.
This week, a few organizations met here in Washington–conservation organizations, philanthropists, scientists, industry–and all agreed that we need more cooperation. We need to work together more strongly if we really want to move the dial in ocean conservation much faster. This coalition, this new network, is called Mission Blue. It’s the leaders of ocean conservation, ocean stakeholders who really want to make a difference by working together after realizing that working alone we are not going to make it.
We are also launching a campaign called I Am the Ocean where we want people to realize that the ocean is linked to them. Everybody is part of the ocean, and the ocean makes this planet such a wonderful place to live. If you go to IAmTheOcean.org, you will be able to see what the coalition is about and also how you can help.
When you talk about the coalition, it puts me in mind of a question that someone posed on National Geographic’s Facebook page. We let our Facebook fans know that this event was taking place this afternoon, and we invited them to ask questions. A number of people did. One person, Michelle Brown, posted a question: What organization is responsible for looking out for our ocean?
There is not a single organization that is looking after the ocean. The ocean is like the last frontier. Governments–federal governments, regional governments, local governments–fisheries management organizations… In the United States, for example, every department but the department for veterans has some stake in the ocean. This is why President Obama has established a national ocean policy with the goal of bringing everything that is ocean related under one single umbrella. Because right now, there are too many cooks in that kitchen.
What we need to do is all together, instead of working in a fragmented way, come together to work together to solve the problems much faster. Because time is short.
Another Facebook follower named George asks “Can the ocean recover itself naturally if pollution is stopped, or does cleaning need to be done manually, and if so, how?”
The ocean always recovers if we give it the chance. The best examples are marine protected areas, these reserves that we have set aside with no fishing. And the marine life comes back. Within a few years–three, five, seven years–we can tell the difference. It’s too late for some species that have gone extinct. But most of the species are still in the sea. So we have a chance to recover them.
Jozsef Nagy asks about dead zones in the ocean. Are governments doing something to address them?
Dead zones are areas on the coast that have almost no oxygen. Most of these areas, like this big area at the mouth of the Mississippi, are caused by all the agricultural and sewage runoff that comes from upstream, from the land. You can see that agriculture in the Midwest in the United States is a huge problem for the marine ecosystems in the Gulf. The problem is that we still don’t have integrated management of our entire country. It’s about time that there were regulations, agricultural regulations on the use of fertilizer for example, implemented taking into account the impact of these fertilizers downstream on the Gulf of Mexico marine ecosystem.
Unfortunately there are no attempts at such scale yet to integrate our upstream activities with what happens in the ocean.
Svetlana Melnichuk wonders whether fish could be bred in, say, fish farms and released into the wild to supplement the supply?
Fish farms are very important to complement the wild catch because the catch we get from the ocean peaked in the late ’80s, and it’s been declining since. We cannot take more fish than we are taking now from the ocean. So aquaculture, fish farms, are increasing, so they’re providing more and more and more protein.
The problem is that we are taking fish from the sea to make fishmeal to feed the fish in the farms. It doesn’t make any sense. And some ask if fish from fish farms could be released in the field to replenish natural populations. And that would be very inefficient, because it takes so much effort to raise these fish, and then these are fish that haven’t grown in the world. Putting them back in the ocean, we’d have problems with the interaction of diseases or parasites.
The best thing we can do is to reduce fishing pressure in the ocean. This is much more effective than trying to raise fish in a farm and then throwing them back in the water. If we set aside some protected areas, if we reduce the fishing capacity, we take many boats out of the ocean, fishes will replenish themselves much more efficiently than if we are trying to engineer it.
Everybody can help. Go to IAmTheOcean.org and find out how you can help.
Read “My Blue Wilderness” by Sylvia Earle in the October 2010 issue of National Geographic magazine, see what Earle had to say after the Talk of the Nation broadcast, learn more about the ocean from National Geographic, get classroom resources for teaching about the oil spill, and find out what you can do to help at I AmThe Ocean.
Ford Cochran directs Mission Programs online for National Geographic. He has written for National Geographic magazine and NG Books, and edits BlogWild–a digest of Society exploration, research, and events–and the Ocean Now blog. Ford studied English literature at the College of William and Mary and biogeochemistry at Harvard and Yale, with a focus on volcanoes, forests, and long-term controls on atmospheric CO2. He was an assistant professor of geology and environmental science at the University of Kentucky before joining the National Geographic staff.
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