Turning the Tide

Our oceans are in trouble, says Nancy Knowlton. But it’s not too late to do something about it

Eric Jaffe

Nancy Knowlton was the founding director of the Center for Marine Biodiversity and Conservation at the Scripps Institution of Oceanography before being hired in 2007 to lead the Smithsonian's Ocean Initiative. As part of this initiative, Knowlton will oversee a new research program and will help develop an ocean Web portal. Knowlton tells Smithsonian.com the problems facing the ocean today—and what we can do to save it.

What is the state of the ocean today?

It's actually very bad. It's probably worse in many ways than the state of conservation on land, but we don't think about it because we don't live in it.

Basically it comes down to what we put into the atmosphere and ocean and what we take out of the ocean. What we put into the atmosphere is carbon dioxide, which makes the ocean hotter. And when it dissolves in the oceans themselves, it makes them more acidic. From the land, you're getting all this runoff into the oceans—vast amounts of nutrients associated with excess fertilizer, pesticides, industrial waste, waste from cars and city streets. There's a lot of stuff that fertilizes the ocean and causes bacteria and other slimy stuff to proliferate, plus things that actually poison the ocean.

We also have the massive scale of fisheries. We're pulling out the tops of the food chain. Most of the big fish in the ocean are already gone. We've also strip-mined the bottom of the sea floor with trawls.

We've basically created a massive disturbance to the ocean, which is resulting in collapsing ecosystems, failing fisheries, toxic blooms.

When did scientists realize the damage we're causing the ocean?

In the last 50 years, things have really deteriorated. People have had some impact for a long time, but the ocean can suffer a certain amount of assault from human activity and not have a major problem with it. Now everything is increasing. Carbon dioxide is increasing dramatically. Industrial fisheries, since about the 1950s, have increased dramatically.

We're starting to really reach what people sometimes call a "tipping point," where whole ecosystems slip into much, much less desirable states. For example, many coral reefs around the world have gone from coral reefs to a rubble bottom covered with seaweed, with very little living coral. That's happened place after place after place.

The ocean is so big that most of the ocean bottom has never even been examined, and we're destroying it. Even presumably well-known marine creatures are not nearly as well-known as we think they are. For example, it's only in the last 20 years that we found out that common mussels that we used to think were one species are actually three species. Turns out there are multiple species of killer whales, not one. And there are vast numbers of species that have never been catalogued or described.

How will these changes affect the planet?

The oceans provide a lot of important things to people. In many places, seafood is the most important high-quality protein. A lot of countries, the United States included, depend on coastal activities for tourism. A big chunk of the world's population—somewhere close to 50 percent—lives close to the oceans. So when the oceans don't work the way they should, there are all sorts of impacts economically and also aesthetically. When beaches are closed due to toxic blooms, it has an economic impact, and it diminishes people's quality of life.

And the idea that people could have such a devastating impact that they rival the effects of an asteroid hitting the planet, in terms of extinction and ecosystem collapse, is upsetting, even apart from the strictly dollars and cents issue.

What can people do to save the ocean?

You can reduce your ecological footprint. If everyone individually were to really take serious steps in terms of energy conservation, we wouldn't solve the CO2 problem, but we'd make an important contribution.

It's not just what we can do ourselves. If the United States takes CO2 seriously, we'll pave the way for other countries to do it.

You can also support industries that are environmentally progressive.

What will happen if changes aren't made?

A lot of the damage has already been done. Every year in the Gulf of Mexico, there's a giant dead zone that forms. The North Atlantic cod collapse cost a fortune in lost jobs in northern New England and Canada, and it's never really recovered. Without action, it's all going to keep getting worse. More fisheries are going to collapse. The beaches will be unusable. It's pretty bad. We have to do something.

What species are in the most trouble?

There's real concern the white abalone could go extinct. The same goes for some shark species, some species of marine mammals and some corals. Once things get really rare, males and females can't find each other to mate. So even though there a few individuals left, they don't reproduce and eventually the population dwindles to extinction. Or, if things really get rare, other things take their place, so it's harder for them to build back up in the ecosystem.

Are there any ocean conservation success stories?

There are lots of waterways that are being cleaned up. Also, there are more marine protected areas, which are a big tool we have to manage things effectively. One-third of the Great Barrier Reef is now a no-take marine reserve. Similarly, the Northwest Hawaiian Islands have been brought into a major reserve system. And California now has a new reserve system. So people are really starting to effectively protect marine areas, which I think is probably one of the most important things we can do for the short term.

There's a lot to be done still. Some fisheries have started to come back, and some fisheries are much better managed than they used to be. It's slow getting people to do things, so the first step is for people to realize the problem. The public awareness of issues associated with climate change has increased enormously in the last five years. But that's the first step. Just being aware of the problem isn't going to solve it.

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