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Shark dive at dive site known a "Tiki", features Gray reef sharks (Carcharhinus amblyrhynchos), highlighted by streaks of sunlight. These majestic animals are frequent visitors to the reefs of Moorea.

Photo by: Stephen Frink

Stephen Frink

Sharks are Nearly Extinct in the World's Reefs

By: Lucy Sherriff

Sharks are “too rare to fulfill their normal role in the ecosystem” according to a new study, and have become “functionally extinct” in one of five of the world’s coral reefs.

August 19, 2020

The study, conducted by Global FinPrint and published in the scientific journal Nature, surveyed 371 reefs in 58 countries.

Sharks were not found on 19% of the reefs, which indicated a “widespread decline that has gone undocumented on this scale until now”, Global FinPrint, a collaboration started by marine biologists Mike Heithaus and Demian Chapman, said.

Global Check-Up

The Dominican Republic, Kenya, Vietnam, Qatar, and the French West Indies are just some of the regions that are essentially devoid of sharks. In 800 hours of observing those nations, just three sharks were spotted.

The group focused on reef sharks, because they are easier to spot than the species in the high seas.

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Humpback snapper (Lutjanus gibbus) break formation to make way for a Silvertip shark (Carcharhinus albimarginatus).

Photo by: Stephen Frink

Stephen Frink

Destructive fishing practices, as a result of dense populations and poor management, were attributed to being one of the main factors involved in species loss.

"Although our study shows substantial negative human impacts on reef shark populations, it's clear the central problem exists in the intersection between high human population densities, destructive fishing practices, and poor governance," according to Demian Chapman, Global FinPrint co-lead and associate professor in the Department of Biological Sciences and Institute of Environment at Florida International University. "We found that robust shark populations can exist alongside people when those people have the will, the means, and a plan to take conservation action."

The research started in 2015, using underwater video cameras strapped to 1.5-meter-long poles, which had been baited and placed in reef ecosystems across the Western Atlantic, Western Indian Ocean, Indo-Pacific, and Pacific regions.

The Proof is in The Pictures

More than 15,000 hours of video footage was captured over the study period, which lasted for four years. More than 700 students helped out review the footage but Heithaus’ mother studied the most - 1,721 hours worth.

"These nations are seeing more sharks in their waters because they have demonstrated good governance on this issue," Aaron MacNeil, lead author of the Global FinPrint study and associate professor at Dalhousie University, said. "From restricting certain gear types and setting catch limits, to national-scale bans on catches and trade, we now have a clear picture of what can be done to limit catches of reef sharks throughout the tropics."

More About Sharks

There's Still A Lot You Don't Know About Sharks 14 Videos

From fintastic facts to jawsome discoveries, this is everything you need to know about the apex predators you know and love, sharks.

This is What is Killing Sharks

Despite sharks sitting at the top of their food chain as an apex predator, they are an endangered species as a result of human activities.

Sharks are especially vulnerable to overfishing as they grow so gradually and don’t have many offspring, and demand for shark fins has grown.

“This study is a tour de force,” Nick Dulvy, a conservation biologist at Simon Fraser University, told Science.

“We really need to substantively move toward conservation and recovery in the next decade, or else we’re going to be in real trouble.”

Next Up

Extinct or Alive? A Question Nearly Impossible to Answer in the Ocean

It’s a big world out there, and there are a lot of places to hide. This is the mentality I take when searching for lost species, a passion I have dedicated my life and career as a wildlife biologist to.

Shark Flings Itself Out of Water to Avoid Becoming Orca’s Snack

A sevengill shark flings itself out of the water and onto rocks to avoid becoming an orca's meal.

Searching for Lost Sharks

Dr. Dave Ebert joined Animal Planet’s Forrest Galante in some of the most shark infested waters in the Southern Hemisphere to track down lost species on EXTINCT OR ALIVE: LAND OF THE LOST SHARKS. He let's us in on his experience.

Swimming with Sharks

One research foundation is working to change public perception of sharks by taking people swimming with them – without a cage.

Endangered Sharks of the World

Our world's oceans are continually challeged by pollution, overfishing, and climate change. This affects sharks just as much as it affects humans--if not more so. Read on to learn about some endangered sharks that need our help.

Sharks of the Twilight Zone

The deep-sea is largely a mystery and we’re finding that it’s a much more biodiverse place than previously thought. There are hundreds of species of sharks that live in cold, dark depths of the deep sea and have adapted to this foreign world. And Beneath the Waves (BTW) is on a mission to learn more!

The Shark Atoll of Palmyra

Palmyra Atoll is an uninhabited coral atoll in the Pacific Ocean that is part of a massive oceanic conservation area known as Pacific Remote Islands Marine National Monument. It's vital to the health of our world's oceans and it's filled with sharks.

The Amazing World of Sharks

Today is Shark Awareness Day! The Explorers Club went live on Facebook to do a deep dive on the importance of sharks in our ecosystem.

New Pocket Shark Discovery

A new Pocket Shark has been discovered and it's insanely cute! Here's what you need to know...
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