Ocean sharks facing extinction

More than half of the world’s wide-ranging ocean sharks are threatened with extinction, international conservation union the …

More than half of the world’s wide-ranging ocean sharks are threatened with extinction, international conservation union the IUCN warned today.

A study of 21 species of oceanic sharks and rays found 11 of them were under threat of being wiped out, the IUCN's Shark Specialist Group (SSG) said.

The research by 15 scientists from 13 different countries found that overfishing is largely to blame for putting the survival of the oceanic species  at risk.

Some 16 of the 21 species looked at, including the thresher shark, the silky shark and the shortfin mako, are at an increased risk of extinction because of being targeted for their fins and meat as well as being caught accidentally by fishermen looking for other fish.

According to the IUCN, most of the catches are unregulated and unsustainable.

The scientists also warned the increasing demand for "shark fin soup" - particularly driven by growing Asian economies - means that the fin is kept and the rest of the animal discarded, often without the catch being recorded.

The study, published in the latest edition of Aquatic Conservation: Marine And Freshwater Ecosystems, says sharks and rays are vulnerable to overfishing because they take a long time to mature and reproduce.

The SSG's report calls for governments to improve monitoring of fisheries catching sharks and rays and establish science-based limits for amount fishermen are allowed to land.

The group also wants to see an end to shark finning, in which the fins are removed and the rest of the fish discarded at sea, and investment in research and population assessments of the species.

Sonja Fordham, co-author of the paper and deputy chair of the SSG, said: "The traditional view of oceanic sharks and rays as fast and powerful leads to a misperception that they are resilient to fishing pressure.

"Despite mounting evidence of decline and increasing threats to these species, there are no international catch limits for oceanic sharks. Our research shows that action is urgently needed on a global level if these fisheries are to be sustainable."

Lead author Nicholas Dulvy, of Simon Fraser University, Vancouver, Canada, said: "We are losing species at a rate 10 to 100 times greater than historic extinction rates.

"Humans are making increasing use of ocean resources, so many more aquatic species, particularly sharks, are coming under threat. But it doesn't have to be like this.

"With sufficient public support and resulting political will, we can turn the tide."

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