Study: Sharks in 20% of the world’s coral reefs are ‘functionally extinct’

According to a study published Wednesday in the journal Nature, about one in five of the world’s coral reefs is now almost extinct. The study, by FinPrint Global, examined 371 coral reefs in 58 countries and found that about 20 percent of the sharks in the reef were “functionally extinct.” This means that while sharks may still be seen on these reefs, “they are not functioning normally in the ecosystem,” study co-author Colin Simpfendorfer, a professor at James Cook University in Australia, said in a press release.

Researchers used data from more than 15,000 bait remote underwater video stations to survey coral reefs to determine how coral reef sharks are around the world. In six countries and territories with 69 coral reefs – the Dominican Republic, the French West Indies, Kenya, Vietnam, the Netherlands Antilles and Qatar – few sharks were observed in more than 800 hours of video surveys.

The study found that the decline in coral reef shark populations was a combined with high human population density, destructive fishing policies and poor governance. Studies have shown that countries and regions that do the best in protecting shark populations – such as Australia, French Polynesia and the United States – often have shark sanctuaries and ban all shark fishing, or have scientific restrictions on how many sharks can be caught.

“We found that powerful shark populations can coexist with humans when these people have the will, the means, and the plan to take protective action,” said study author Andian Chapman, a professor at Florida International University.