'One in 15 sharks dies each year from fishing'


Around 100 million sharks are killed by fisheries every year, according to a new study.

The research, published in Marine Policy, highlights the global unsustainability of shark fisheries.

"Sharks have persisted for at least 400 million years and are one of the oldest vertebrate groups on the planet. However, these predators are experiencing population declines significant enough to cause global concern", explains lead author of the paper Boris Worm, professor of biology at Dalhousie University.

It's estimated that between 6.4% and 7.9% of all sharks are killed each year. The trade in shark fins is still a leading factor in their overfishing, and because sharks grow relatively slowly, maturing late in life and producing few offspring, there's little question that they are being caught faster than they can reproduce.

"Our analysis shows that 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," says Worm.

The disappearance of sharks also affects the ecosystem. Co-author Mike Heithaus of Florida International University, explains: "In working with tiger sharks, we’ve seen that if we don’t have enough of these predators around, it causes cascading changes in the ecosystem, that trickle all the way down to marine plants."

Researchers say that if we are to prevent the extinction of many species of sharks, more nations need to invest in sustainable shark fisheries management, including catch limits, trade regulation and other protective measures for the most shark vulnerable species.

The Convention on International Trade in Endangered Species (CITES) meeting in Bangkok will consider greater protection of vulnerable species of shark including oceanic whitecap, porbeagles, and several types of hammerhead.

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