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.


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