"Even though FAO statistics are the most exhaustive data available on world production and trade of fish and fishery products, they are also likely to underestimate the actual world production and trade volumes of specific species and products, such as sharks," the pair said in an interview. "Some data may be misleading if employed to deduce the respective importance, or trends for, various [shark] products."
FAO staff have since revised their initial estimates to reflect substantial increases to their estimated volume of shark fin trade in 2000 and 2001. Such revisions are not atypical. FAO staff say they often refine analysis of previously collected national fisheries data. (However, overall 2001 trade levels declined, outside researchers note.)
Cripoldi and Vannuccini said that steps to improve fishery statistics on sharks include developing better methods to gather data on fishing takes and increasing fishery observer programs. FAO is undertaking such initiatives as part of the organization's international shark conservation and management plan.
Because such plans are sometimes difficult to implement, the use of trade statistics to monitor fishing takes holds promise.
" They often provide a basis for supplementing, controlling, and validating catches through data sources not directly related to fishing," Crispoldi and Vannuccini said.
Crispoldi and Vannuccini noted one shortcoming: Trade statistics often fail to identify specific shark species.
Asian Demand High, Conservation Awareness Low
Throughout much of East Asia, dried seafood is both a popular food source and ingredient used in traditional medicines. Demand for dried seafood in China alone, with a population of 1.3-billion, is enormous.
Shark fin, known in China as yu chi or "fish wing," is used to make shark fin soup a delicacy widely consumed in China since at least the start of the Sung dynasty in 960 A.D.
Trade in shark fins is a lucrative business. Depending on the species, shark fins can sell for U.S. $400 per kilogram (U.S. $880 per pound) or more in Hong Kong. Some 30 to 40 species are commonly traded.
Sharks were once ignored by many commercial fishermen. But they've become more desirable as other fish species disappear due to over-fishing. Sharks reproduce slowly. As a result shark stocks are slow to rebound once their populations have been diminished.
Shark fins from Europe now dominate the Hong Kong shark fin import market, according to the WCS study. While European imports were negligible as recently as the early 1990s, they now account for about 27 percent of the total figure. Nearly all of those sharks are harvested by Spanish fishing fleets, whose other traditional commercial fish species have declined.
In the Sai Yun Pun district, Clarke found that most dried seafood traders had little knowledge of the natural history of their trade goods or the conservation issues surrounding them. "The trade community as a whole is pretty unaware," said Clarke. "The traders in abalone and sea cucumber didn't have any sense of whether they were taking too many of the organisms, and whether 10 years down the line there might not be much left. That's a new concept for them."
Clarke said shark fin dealers were more aware of conservation efforts. "They know that people are trying to curb that trade, but they don't believe that there's a problem with shark numbers."
Clarke hopes that her trade-based approach can become a valuable tool in global efforts to conserve marine resources.
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