The movie “Jaws” created the notion of sharks as powerful eating machines who stalk humans. Yet ironically, in the 35 years since that movie debuted, it’s sharks that have been driven nearly extinct by humans.

Around the world, about 10 people are killed by sharks annually. But every year humans kill up to 73 million sharks. These numbers are unsustainable, and as a result, shark populations have been decimated — many dropping 90 to 99 percent over the last few decades.

It’s largely because of a status symbol dish popular in Asia: shark fin soup. As Asian economies have boomed, particularly China’s, demand for shark fin soup has exploded. The San Francisco Bay Area has one of the largest Chinese populations outside of Asia, so activists here are trying to stop the excesses of the shark fin fishery.

There are more than 440 species of shark worldwide, many of which serve as the keystone in their various ecosystems. The San Francisco Bay is home to several species: the spiny dogfish, the seven-gill, the leopard, brown smoothhound, and the unfortunately named soupfin. Other sharks, including great whites, visit seasonally.

Many people consider sharks to be ruthless, violent creatures: they attack, and they kill. But when humans hunt sharks, the result is basically torture. “Fishermen capture sharks anyway they can, in nets or on longlines or just on handlines … get it on board the boat, and then cut the fins off. They then throw the writhing shark back overboard, ” said John McCosker,  a scientist and chair of aquatic biology at the California Academy of Sciences.

He’s been studying sharks for almost 50 years. He said that “a shark without its fins is bound to die.” Fishermen don’t keep the whole shark because the rest of the meat is not as valuable. “Either it will bleed to death, or it will be unable to swim, unable to feed. And it’s only a matter of hours or days that it will survive before it finally dies … Shark finning is a horrific thing to do,” he said.

Yet, the economics of selling fins is alluring: a bowl of soup containing just a few ounces of shark fin can cost $100. But this massacre is devastating entire ecosystems. For example, when East Coast sharks were overfished, ray populations took off. Rays ate too many scallops, and fishermen lost out. So the United States and some other countries have made the practice of finning illegal by mandating that sharks be brought in with fins attached. The policy is meant to slow the slaughter by limiting the number of sharks that can be taken at one time. But without unilateral support, it’s not very effective. And because many species travel great distances through international waters, the U.S. law does not protect some sharks native to the Bay Area, including the great white.

In fact, enforcement of fins-attached policies is nearly impossible, so the conservation group WildAid is trying to temper demand through educational campaigns. WildAid runs ads in China, including one featuring basketball superstar Yao Ming. Now it’s rolling out a campaign in San Francisco, where executive director Peter Knights lives and works.

Knights plans to buy billboards on Muni and has already sent information in Cantonese to restaurants. He says WildAid has learned to tread carefully when talking to another culture about its practices. “We have Yao Ming and Olympic athletes and celebrities delivering the message themselves. So it’s not Westerners saying, ‘Chinese, don’t do this.’ It’s Chinese saying, ‘Chinese, please don’t do this.’ I think that’s vital in how you deliver such a message,” he said.

Many of the thousands of Chinese restaurants in the Bay Area sell shark fin soup. Shops in San Francisco’s Chinatown and other areas serving Asian immigrants are stocked with jars upon jars of shark fins, some selling for more than $400 per pound. Most restaurant and shop owners won’t discuss their shark fin trade, but those who do say they don’t sell very much anymore, mostly because it’s so expensive.

Newton Szeto works at a restaurant on Clement Street. He says they don’t sell a lot of shark fin but have it on the menu to attract wedding parties and banquets. He says that his restaurant keeps very little shark fin on hand. But if someone orders a big banquet, the staff goes out and buys some. Nevertheless, he says he understands the cruelty of shark finning. “I know it’s very important for the shark. Because they don’t kill them. They take the shark fin out; they don’t kill them, just kick them back in the sea. I understand what you feel, OK? But for the business, OK? We have to do that,” Szeto said.

Aside from environmental and cost concerns, the decline in Bay Area demand may be a result of people learning about the deleterious health effects of eating shark. “Shark fins are high in mercury. Many are high in formaldehyde and other chemicals that cause reproductive harm, cause developmental diseases, cause a number of adverse health effects,” said David McGuire,  founder of Sea Stewards, a group devoted to restoring health to the San Francisco Bay.

But even these health concerns have not stopped the trade. So McGuire is working with state assembly members Jared Huffman and Paul Fong to make selling shark fins illegal in California. Hawaii instituted such a ban in 2010.However, it’s China that remains the biggest market.

Knights says it would take a sales ban there — similar to the one proposed for California — for shark populations to recover. “We tend to malign sharks. We tend to not care about sharks. We think sharks are evil or dangerous when, in fact, sharks are very important. And by protecting sharks, we’re protecting the whole ocean food chain, the whole web of life, and that includes humans,” said McGuire.

Funding for this story was provided bySpot.us. This story was reported on KALW Crosscurrents which also provided the editing, and was also run on the SF Public Press.

Tags: conservation, San Francisco, shark fins, sharks