NEW STUDY: Reef sharks are at a much higher risk of extinction than previously thought
Protected areas and fisheries management key to survival
WATCH: This BRUV footage shows the type of data collected in a monumental global study. This research amassed 22,000 hours of footage from 391 reefs in 67 territories to reveal the impact of overfishing on our reef sharks. Video: Global FinPrint.
Overfishing is driving reef sharks toward extinction, according to new study published in Science.
The five main shark species that live on coral reefs — grey reef, blacktip reef, whitetip reef, nurse and Caribbean reef sharks — have declined globally by an average of 63 percent, according to the scientists of Global FinPrint, a five-year international study supported by the Paul G. Allen Family Foundation.
Co-founder of the Marine Megafauna Foundation, Dr. Andrea Marshall (below), Mozambique Research Manager Anna Flam, and Researcher Alex Watts co-authored the study and collaborated on the Mozambique fieldwork.
Dr. Marshall deploys a BRUV in Mozambique. Photo: MMF
“These are some of the best estimates of population decline of widespread shark species because of the very large number of reefs and countries sampled,” according to Colin Simpfendorfer, lead author of the study and adjunct professor of Marine and Aquaculture Science at James Cook University in Australia. “This tells us the problem for sharks on coral reefs is far worse and more widespread than anyone thought.”
Results from this latest research, which includes 22,000 hours of video footage from baited underwater video stations across 391 reefs in 67 nations and territories, indicates widespread overfishing is the main culprit driving reef sharks toward extinction.
Sharks and rays are common in coral reef ecosystems, but as reefs are more heavily fished, they have become stripped of both shark and ray species or stripped of just shark species, leaving the ecosystem dominated by rays. The loss of sharks could have an impact on the overall health and function of the coral reef ecosystem.
Dr. Marshall sending up the BRUV with a lift bag. Photo: MMF
“While overfishing and poor governance is associated with the absence of these species, they are still common in Marine Protected Areas (MPAs) and places where shark fishing was banned or highly regulated,” said Demian Chapman, lead scientist of Global FinPrint and director of the Sharks and Rays Conservation Program at Mote Marine Laboratory. “Reef sharks can be important for human livelihoods through dive tourism and if fished carefully. An investment in reef shark conservation can therefore be good for people, too”.
Early results from this study were previously used to update the status of four of these species to more threatened categories on the International Union for the Conservation of Natures (IUCN) Red List. They were also presented during the most recent Conference of the Parties of the Convention on the International Trade in Endangered Species of Wild Fauna and Flora (CITES), helping world governments to make the groundbreaking decision to better regulate trade in these and more than 50 additional species of sharks.
Bowmouth from MMF’s BRUV in Mozambique. Photo: MMF
“This means no trade should come from nations where the take of the species will threaten its survival,” Simpfendorfer said. “This study can be used to help identify those nations where such catches would be detrimental. We need to act now to stop widespread extinction of shark species in many parts of the world.”
Flam says that in Mozambique, “MMF is working with management in the Bazaruto Archipelago and the Sanctuary to protect sharks, encouraging participatory action with local communities in areas lacking national-level protection.”
More than 150 researchers from more than 120 institutions across the world contributed to the research.
The full study, “Widespread diversity deficits of coral reef sharks and rays”, is available at: https://www.science.org/doi/10.1126/science.ade4884
About the Marine Megafauna Foundation
The Marine Megafauna Foundation (MMF) is a registered 501(c)(3) non-profit conservation organization based in the USA. Established in 2009, MMF's mission is to research, protect, and conserve the populations of threatened marine megafauna worldwide. Headquartered in Palm Beach, Florida, MMF focuses on large marine species, such as sharks, rays, and sea turtles, collectively known as 'megafauna'. For further details, please visit www.marinemegafauna.org or follow us on Twitter, Facebook, Instagram, and LinkedIn.
About Global FinPrint
A Paul G. Allen initiative led by researchers at Florida International University, Global FinPrint has united researchers and collaborators from around the world to study sharks, rays and other marine life on coral reefs using baited remote underwater video systems (BRUVS) surveys - assessing coral reef sharks and rays on a global scale for the first time. For further details please visit globalfinprint.org.
