Who Says Sharks Haven't Evolved?

(Top, photo) AMNH/F. Ippolito; (Bottom, digital image) AMNH/A. Pradel

ScienceShot: The Great Shark Massacre

Sharks have become the underdog of the oceans. They reproduce slowly and are being targeted for their fins and caught accidentally in the hunt for fish. Now, researchers have created the first global estimate of the carnage. By combining data from fisheries organizations and the scientific literature, the team reports in Marine Policy that 97 million sharks were killed in 2010 and perhaps as many as 273 million. "This is the best attempt, published to date, to bring together the available data to quantify fisheries impacts on sharks at a global scale," says John Musick, a shark expert at the Virginia Institute of Marine Science in Gloucester Point. The dire figure implies that more sharks are being taken than are born, jeopardizing their future. George Burgess of the Florida Museum of Natural History in Gainesville points out that the calculation required numerous assumptions, including a single weight estimate for all sharks. Nevertheless, Burgess says, experts agree that sharks are in deep trouble. "It's just a matter of how bad off." The authors argue that sharks need stronger protections, such as the kind of international agreement that has protected whales, or restrictions to the trade of their fins and meat. Several such proposals will be considered this month as the Conference of the Parties to the Convention on International Trade in Endangered Species of Wild Fauna and Flora meets in Bangkok.

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