Sharks are top ocean predators and necessary for the health and balance of the web of marine life. Because they grow slowly and produce few young, their numbers are slow to recover.
Scientists have identified 1,045 shark and ray species, and 30 percent of them are listed as threatened or near threatened with extinction, the Pew Environment Group reported. And because sharks travel far and are difficult to count, scientists don't have enough information to assess the population status of 47 percent of the species.
The environmental group said that up to 73 million sharks are killed annually for what it said was a globally unregulated and unsustainable shark-fin trade.
President Johnson Toribiong of Palau declared his nation's waters as the first sanctuary for sharks last year.
"We have done what we can in Palau's waters to save these magnificent masters of the sea," Toribiong said. "We have found that healthy shark populations keep our marine environment healthy and our tourism industry thriving."
Honduran President Porfirio Lobo Sosa, who banned shark fishing in February, said the price of shark fins is driving fishermen around the world to evade rules intended to conserve sharks.
The U.S. and many other countries allow fishing for sharks. The National Marine Fisheries Service sets quotas and restrictions on shark fishing and prohibits fishing for sharks species whose numbers are depleted, said spokeswoman Monica Allen.
Toribiong and Lobo called on other countries to establish shark sanctuaries and ban shark finning — the practice of cutting off the fin and leaving the shark to die. The meat of two species of sharks is eaten, but the vast majority of shark species are fished only for their fins.
The member nations of the Convention on International Trade of Endangered Species of Wild Fauna and Flora voted against a proposal in March to protect several species of sharks.
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