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IN DEEP

Despite reigning at the top of their food chain, sharks are still in trouble, ecologically

Sunday, April 8, 2007

Sean Van Sommeran looked out of place in the apothecary's shop on Grant Street in San Francisco's Chinatown: A stocky, muscular Caucasian of average height dressed in work-worn clothes, his face tanned and creased from a life largely spent outdoors. Surrounded by their stock -- medicinal and culinary roots, herbal decoctions and dried animal parts -- the Chinese clerks regarded him warily.

But Van Sommeran, director of the Pelagic Shark Research Foundation, a gadfly group in Santa Cruz that both gathers data on Pacific sharks and lobbies for their protection, seemed utterly at ease, indifferent to the low-level inhospitable vibes emanating from the shop's owners.

He was focused instead on the dried shark fins arrayed behind the counter. The stock was impressive: Big plastic bags and jars crammed with fins, each container labeled with a price tag, ranging from $168 to $450 a pound. These dried fins, used in soups considered the ne plus ultra of Chinese cuisine, were among the most expensive animal products in the world.

"Lots of black-tipped reef sharks there," said Van Sommeran, pointing at bags full of small, gray fins with dusty black spots. "Pectoral fins, mostly."

He shifted his attention to a jar filled with slightly larger fins. "Those could be lemon sharks. With some species, it's impossible to tell without a DNA test."

Above the display were four huge fins arrayed like a heraldic device.

"Wow, those are really impressive," Van Sommeran said. "The two big ones look like hammerhead pectorals. The other two probably come from basking sharks -- the second-biggest fish on the planet. They'd bring $1,000 to $2,000 each." Van Sommeran essayed a few friendly words in fractured Cantonese to the shop owners as he left, but elicited only gelid stares.

Back on the street, Van Sommeran discussed the store's stock. The fins, he allowed, could be either legal or illegal: The regulations governing their import are complicated and abstruse, and it can be impossible to determine the provenance of a given fin without extensive tests.

"But I'll tell you what's interesting," he said. "A few years ago, when I came through these stores, the fins were mainly pelagic species -- open-water fish like blue and great white sharks. Now they seem to be mainly reef or coastal sharks, mostly from tropical areas.''

That could be indirect good news for sharks that inhabit California waters, Van Sommeran said: Federal and state regulations passed in recent years to protect sharks may be having a salutary effect.

"But the demand for shark fin is high, higher than it's ever been," he said. "And in the absence of solid, enforceable international regulations, it's going to be satisfied one way or the other."

Van Sommeran is controversial in ichthyology circles. A former commercial tuna fishermen, he founded his organization after it became evident that the big pelagic fish he was targeting were disappearing.

He hasn't any meaningful academic credentials, and he has proved more than willing -- far too willing, his detractors say -- to go toe-to-toe with people who do. But he has logged an immense amount of time on the water, and few scientists have accumulated such extensive empirical field knowledge of California's sharks. His ad hoc group was one of the first organizations to tag large numbers of blue, great white and basking sharks to determine range and migratory patterns.

"Sean may rub some people the wrong way, but he does produce some good data," said Ken Goddard, the director of the National Fish and Wildlife Forensic Lab in Ashland, Ore. Goddard is compiling a DNA database on Pacific sharks to aid federal agents trying to build legal cases against purveyors of illegal shark fins; Van Sommeran has collected tissue samples for the project.

Data on shark populations -- global or regional -- is scant, said Goddard. And as a wildlife forensic researcher, he said, he is hardly qualified to provide detailed analyses of their status. But the very fact that federal wildlife agents need the database he is working on, he allowed, indicates something dire is amiss in the ocean.

"My sense of the fin trade is that it's very significant," Goddard said. "One thing I've been doing recently is working on protocols for damaged coral reefs. Some of the scientists I've talked to on that project have spent a lot of time in the water, and they tell me that shark populations are massively depleted pretty much everywhere they go. They just don't see the numbers of sharks they used to see, and they see very few large sharks."

John McCosker, the chairman of aquatic sciences at the California Academy of Sciences in San Francisco, is more emphatic.

"Sharks are disappearing worldwide," he said. "The estimate bandied about in my circles is about 100 million slaughtered each year. And I say slaughtered, because that's what it is -- killing large, long-lived, slow-growing, slow-maturing animals just for their fins."

As far as is known, said McCosker, no species of shark has gone extinct from fishing or other human activity, "but many species in many parts of the world are functionally extinct, ecologically extinct," he said. "They can no longer perform their essential roles as the top predators in marine ecosystems. There aren't enough of them."

The simple fact anyone cares that sharks may be on the cusp of disappearing must be considered progress of a sort. Thirty years ago, the prevailing metaphor for sharks was "Jaws." The only good shark was a dead one, and interest in them was restricted to the tastier varieties -- most particularly thresher sharks, which yield succulent, rich meat similar to swordfish.

But in recent years, sharks have enjoyed some positive public relations. In this country, they are now generally considered interesting creatures worthy of protection. Some of the more charismatic species -- great whites, tiger sharks, makos -- are acknowledged as beautiful in the fierce, implacable way that wolves and leopards are beautiful.

It's not surprising, then, that California's sharks seem to be doing nominally better than sharks native to African, Asian or South American waters, where they remain little more than commodities to be eaten or sold -- or bogies to be feared.

Joe Bizzarro, a research scientist with the Pacific Shark Research Center at Moss Landing Marine Laboratories (not to be confused with Van Sommeran's group), emphasized that there is no extensive population database as yet for sharks of the eastern Pacific. Nevertheless, said Bizzarro, the "trajectory" for many species appears generally positive.

Great white sharks were designated a protected species by the state of California in 1994, and basking sharks received the same status in 2000. While baskers remain an utter enigma -- they show up unpredictably offshore in small pods, cruising the surface with their gigantic maws agape to scoop up plankton, then disappear for months or years at a time -- great whites seem to be doing pretty well, said Bizzarro.

And angel sharks -- a once-common, rather flat shark that somewhat resembles a skate or ray -- also seem to be on the upswing, he said.

"Back in the 1980s, angel sharks used to be a common ingredient in restaurant fish tacos," Bizzarro said. "They were a major catch for the coastal gill net fishery. But the gill nets have since been moved to deeper water, and a giant processing plant in Mexico has been shut down."

Likewise, said Bizzarro, mako and thresher sharks have benefited from the 2000 closing of the high seas drift gill net fishery, which operated in non-territorial waters.

"The nets primarily targeted swordfish, but there was a huge by-catch of threshers and makos off Southern California," Bizzarro said. "Those waters are a nursery area for both species, so the closure of the high seas fishery is a positive development."

But a significant potential threat to the state's mako and thresher populations remains: the recreational tournament fishing industry, which has boomed in recent years due to the growing popularity of sport fishing shows on outdoor and sport cable TV networks. Between 2000 and 2004, said Bizzarro, about 5,000 makos and 2,500 threshers were caught off Southern California's coast each year.

"We'd really like to see the shark tournaments go the way of many billfish tournaments, which now emphasize catch and release," said Heidi Dewar, a research biologist with the fisheries branch of the National Oceanic & Atmospheric Administration. "There would still be some mortality, but it'd be preferable to the current situation."

While the glamorous pelagic, or open-water, species such as great whites and makos get most of the attention, California's waters also support a generous array of estuarine sharks.

Greg Caillet, a professor of ichthyology at Moss Landing Marine Laboratories, said most of California's estuarine sharks also seem to be doing reasonably well. That includes perhaps the best-known species, the leopard shark -- familiar to anyone who has dredged a gobbet of squid or a ripe anchovy across the bottom of San Francisco Bay for any period of time.

Still, even leopard sharks are vulnerable to poaching. The slim, spotted fish were in the news recently, when a preacher associated with the Rev. Sun Myung Moon was apprehended for illegally capturing hundreds of juvenile leopard sharks in San Francisco Bay for the saltwater aquarium trade.

And many researchers caution that "optimism" and "stability" are relative terms when used in regard to shark populations. Along with wholesale finning and sport tournaments, they say, sharks remain threatened by many sanctioned fisheries, such as the drift gill net fishery currently allowed in U.S. territorial waters (not to be confused with the generally proscribed high seas drift gill net fishery that occurred beyond national territorial limits).

The U.S. gill net fishery targets swordfish, said Suzanne Kohin, a research fisheries biologist with NOAA Fisheries. Gill nets are highly efficient at catching swordfish, but they also take large numbers of other pelagic fish, a cohort known collectively as by-catch. Blue sharks -- gracile, large sharks that range worldwide -- comprise a significant portion of the drift net by-catch. Fishermen are required to release any sharks found in their nets, Kohin said, but the mortality rate is high, typically running more than 65 percent.

"We should always be cautious when evaluating data on sharks, because it's incomplete," said Kohin. "But given that, I would never say they're in great shape, and that we have no reason to be concerned."

McCosker sees the situation in terms that are far darker -- even apocalyptic. Sharks of the eastern Pacific -- which includes California -- are as threatened as those from any other region, he said. Any determination that doesn't reach this conclusion, he observed, could be due to "shifting baselines" -- evaluating the stability of a population through current numbers rather than trying to establish any connection to past populations.

McCosker uses blue sharks to illustrate his point. When he was first studying marine biology in the 1960s, he said, blue sharks were cited by his professors as the world's most common large fish.

"They were cosmopolitan in distribution, and their populations were extremely large," he said. "Anybody who fished for salmon or rockfish off California during those years knows that. Blue sharks swarmed around the boats. It was hard at times to get any fish aboard before the sharks got them."

Now, said McCosker, a sighting of a blue shark off the California coast is a noteworthy event.

"I do a lot of salmon fishing, and I don't recall seeing one blue shark last year," McCosker said, his voice charged with emotion. "To the oceans, these animals are like lions are to the Serengeti. We're at the brink of an unthinkable catastrophe."

E-mail Glen Martin at glenmartin@sfchronicle.com.

http://sfgate.com/cgi-bin/article.cgi?f=/c/a/2007/04/08/CMGSVOLD181.DTL

This article appeared on page CM - 6 of the San Francisco Chronicle, © Hearst Communication


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