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  SignonSanDiego 17 Sep 06
Researcher studies impact of humans on the oceans
By Bruce Lieberman UNION-TRIBUNE STAFF WRITER

Enric Sala waited 36 years to see the ocean of his dreams. The day came last fall during an expedition to the remote Line Islands 1,000 miles south of Hawaii. Sala, a marine ecologist at the Scripps Institution of Oceanography in La Jolla, began his first day by scuba diving in Kingman Reef – among the most remote of the Line Islands.

He and his colleagues found themselves surrounded by a forest of colorful coral and pockets of tropical fish. Then sharks came to check out the researchers. It's likely that these predators had never seen humans.

Sala remembers feeling like a 21st-century Charles Darwin, the 19th-century naturalist who was among the first Europeans to explore the Galapagos Islands off Ecuador.

Darwin marveled at creatures that showed no fear of him. “I was well aware of the impacts of humans (on the oceans), but not until I had that experience did I realize what we've lost,” Sala said of his dives at Kingman Reef. “It was a very emotional experience.”

Sala is under no illusions that U.S. coastal waters can ever return to the kind of Eden he saw at Kingman Reef. But he has spent years designing and promoting marine reserves in hopes that their limits on fishing and harvesting of other sea life will at least nudge them toward that unspoiled state.

Sala is a supporter of mounting efforts by California officials, conservationists and scientists to enlarge the state's network of marine reserves.

The expansion plan – much criticized by the seafood industry – will be a prominent topic at the California and the World Ocean conference, which starts today in Long Beach. By exploring the Line Islands, Sala and his colleagues hope to establish a baseline – an idea of what the oceans looked like before humans began overfishing and polluting them.

Marine conservation is a tricky business, in large part because it's tough to know what a truly healthy ocean environment looks like or what exactly needs protecting so a damaged ecosystem can recover.

“We have a historical memory of the land, so we know that there were all these bison, lions, tigers, bears and wolves,” Sala said. “But we have no historical memory of the sea.”

The abundance of sharks at Kingman Reef revealed a key feature of thriving ocean habitats: They are full of top predators.

In the Mediterranean, Caribbean, Gulf of California and other degraded ocean waters, sharks, giant groupers, snappers and other predators have grown increasingly rare.

Smaller fish, shrimp, sea urchins and other creatures that otherwise would be eaten by large predators have proliferated in many of those areas.

In contrast, Sala said, sharks consume 85 percent of the biomass – or weight of living things – at Kingman Reef. Studies by him and other researchers have shown that places such as Kingman Reef have five times the biomass of a degraded ocean environment. Tiny fish and clouds of shrimp may look like a lot of sea life, but they're dwarfed in weight by sharks and other big predators.

San Diego County's coastline has lost much of its top-of-the-chain eaters, including its historical abundance of broomtail grouper, black sea bass and a variety of sharks, said Ed Parnell, a Scripps researcher who has worked to redesign marine reserves off La Jolla and Point Loma.

Overfishing, pollution and the rise of invasive species have dramatically altered the local marine landscape, he said.

San Diego Bay used to have major populations of yellowtail tuna, pismo clams, abalone and 10-pound lobsters, Parnell recalled. “We've removed some of the key players and brought others in,” he said. “We've completely changed the system.”

Sala's passion for ocean conservation began in the 1960s and '70s, when as a child he found himself engrossed in watching “The Undersea World of Jacques Cousteau” on television. “When I was a kid, I wanted to be a diver on (Cousteau's ship),” he said.

Raised in Spain, he spent long hours at Costa Brava, a rocky shoreline close to the border with France. Sala later studied marine biology at the University of Barcelona. During the summers, he attended classes in Marseilles, France, a mecca for marine biology and scuba diving.

For his Ph.D., Sala analyzed the effects of fishing on marine environments and how reserves might be designed to best preserve entire ecosystems rather than one or two species. He initially studied the kelp forests off La Jolla, then switched to the Gulf of California, also known as the Sea of Cortez.

Chronically overfished, the Gulf of California is a shadow of its former glory. In the 1970s, fishermen caught sharks and big groupers, casting aside smaller snappers and other fish. But as the large catch began to disappear, fishermen moved on to the smaller fish they once devalued.

The phenomenon of “fishing down the food chain” is a global one. Today, 90 percent of the biggest fish worldwide are gone, studies have shown.

It's been difficult to establish marine reserves in the Gulf of California, Sala said. He and other scientists have given conservation groups the data they need to form reserves large enough to be effective, but government officials haven't cooperated because of opposition from fishing interests.

“There is still not enough public demand for conservation,” Sala said.

In 2008, he plans to return to the Line Islands for more studies. After completing his dives last fall at Kingman Reef, Sala took a flight from Hawaii back to Southern California. As his plane reached Los Angeles and the city's lights filled his window, Sala said he thought about how the world's growing population is ultimately affecting places such as Kingman Reef.

“I was thinking about how many L.A.s there were in the world, and how many Kingman Reefs,” he said, letting out a long sigh. “It was depressing.”
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