Humans now kill 80 million sharks per year, 25 million of which are threatened species

An estimated 80 million sharks are dying in fisheries each year despite global regulations aimed at protecting them from finning, scientists have discovered. 

In a study published Jan. 11 in the journal Science, researchers used data from 2012 to 2019 — when legislation to protect sharks from finning increased tenfold — and found that annual shark mortality rose from 76 million in 2012 to over 80 million in 2017. Of those shark deaths, 25 million, or over 30%, represented threatened species. 

The researchers reviewed fisheries data from 150 countries and in the high seas, as well as using computer modeling and interviews with experts — including scientists, governments, environmental advocates and fisheries workers — to check their estimates. 

"We tried to be as proactive as possible in getting the highest-quality data," lead author Boris Worm, a marine ecologist at Dalhousie University in Canada, told Live Science. "I don't think anyone has ever looked at this question at this scale." 

Overfishing is a huge threat for sharks, which are often targeted for their fins or accidentally killed as bycatch. But the study revealed that legislation to prevent shark finning hasn't reduced the number of sharks killed and may have even caused it to increase.

"That's a big concern, because one in three species is threatened with extinction," Worm said.

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