Aggressive overfishing threatens to push some shark species to extinction, and a new study puts annual shark deaths at 100 million.
"Our analysis shows that about one in 15 sharks gets killed by fisheries every year," study leader Boris Worm, a professor of biology at Canada's Dalhousie University, said in a statement. "With an increasing demand for their fins, sharks are more vulnerable today than ever before."
Based on available data for shark deaths and estimates of unreported illegal catches, the researchers estimated that 100 million sharks were killed in 2000 and 97 million in 2010. But since scientists lack sufficient data on shark catches, they say the real number of annual shark deaths could possibly be between 63 million and 273 million.
Sharks are fished for their meat, liver oil, cartilage and valuable fins, which are hacked off, often from live sharks, to be used in shark fin soup, an ancient and prized delicacy in East Asia. Since sharks have slow growth and reproductive rates, it can be tough for their populations to bounce back from big losses.