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100 million sharks killed annually, researchers estimate

Steve Kessel was attending a conference in Vancouver last year when he went in to a local restaurant and noticed that shark fin soup had been scratched off the menu. He wasn’t sure if it was simply because it wasn’t available, but the ecologist in him hoped the eatery was taking the moral high ground by voluntary banning it from the establishment.

Steve Kessel

Steve Kessel.

A post-doctoral research fellow in the university’s Great Lakes Institute for Environmental Research, Dr. Kessel is a shark scientist and part of group of authors that published an article on Friday in the journal Marine Policy which estimates that globally, sharks are disappearing off the face of the earth at mind-boggling rate of nearly 100 million a year, the majority of them to support the shark-fin soup market.

“I hope this really generates a greater awareness about the importance of shark conservation on a global scale,” Kessel said of the paper Global Catches, Exploitation Rates and Rebuilding Options for Sharks, which includes co-authors from Dalhousie University, Stony Brook University in New York, Florida International University in Miami and the University of Miami.

Based on data collected for the study, shark deaths were estimated at 100 million in 2000 and 97 million in 2010. The total possible range of mortality is between 63 and 273 million annually.

Kessel sat on a committee that analyzed data collected largely from catch reports filed through a global data base housed in the fisheries and aquaculture division of the United Nations’ Food and Agriculture Organization, as well as previously published research literature on the subject.

His own research on tracking the migratory patterns and behaviours of sharks has taken him to the Canadian Arctic, the Red Sea off the coast of Sudan, Egypt, the Bahamas and a number of locations along the eastern seaboard. He’s studied a wide variety of sharks including hammerheads, tigers, lemons, grey reefs, bulls, blacktips, and Greenland sharks.

“It’s extremely important to protect them,” said Kessel, who also sits on a sub-committee for a PEW research centre environmental advisory board called Global Shark Conservation. “There are more than 400 species globally, and they inhabit every marine system we’re aware of. They’re a top predator, and the health of so many ecosystems depends on them.”

The paper’s authors say the biggest culprit in the population decline is a combination of a global boom in shark fishing — usually for their valuable fins — and their slow growth and reproductive rates.

“Sharks are similar to whales, and humans, in that they mature late in life and have few offspring,” said Boris Worm, lead author and professor of biology at Dalhousie. “They cannot sustain much additional mortality. About one in 15 sharks gets killed by fisheries every year. With an increasing demand for their fins, sharks are more vulnerable today than ever before.”

Kessel hopes the paper’s release will support the campaign for more sharks being included on the lists of the Convention of International Trade in Endangered Species, which began its annual convention in Bangkok yesterday. He also hopes it will result in more countries establishing “shark sanctuaries” – designated areas where it’s illegal to fish for sharks – as well as bans on fin possession.

Read a Washington Post article about the study.

 

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