Global FinPrint recently revealed the results of a landmark study that used baited remote underwater video cameras to survey living populations of sharks across the world.
Their findings reveal that sharks are absent and functionally extinct on some of the world’s coral reefs - too rare to fulfill their normal role in the ecosystem.
Sharks were absent on nearly 20 percent of the 371 reefs surveyed in 58 countries, indicating a decline that has gone undocumented on this scale until now. However, the Global FinPrint team, led by researchers at FIU, also identified conservation measures that could lead to recovery of these iconic predators.
"The data collected from the first-ever worldwide survey of sharks on coral reefs can guide meaningful, long-term conservation plans for protecting the reef sharks that remain."
Many shark species found on reefs are important food resources, tourism attractions, and top predators - vital parts of the ecosystem and of significant importance to people that live close to these reefs. Their loss is blamed on overfishing, particularly the use of destructive fishing practices such as longlines and gillnets.
“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,” said Demian Chapman, Global FinPrint co-lead. “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 study revealed where shark conservation is working and the specific actions that can work - with Australia, the Bahamas, the Federated States of Micronesia, French Polynesia, the Maldives and the United States all being highlighted. Key attributes of these nations - being well-governed and either banning all shark fishing or having strong, science-based management limiting how many sharks can be caught - were found to be associated with higher populations of sharks.
The researchers are now looking at whether recovery of shark populations requires management of the wider ecosystem to ensure there are enough reef fish to feed these predators.
“Now that the survey is complete, we are also investigating how the loss of sharks can destabilize reef ecosystems,” said Mike Heithaus, Global FinPrint co-lead. “At a time when corals are struggling to survive in a changing climate, losing reef sharks could have dire long-term consequences for entire reef systems.”
Whilst the Global FinPrint survey has revealed a dramatic loss of shark populations across the globe, it has also revealed what is possible with conservation measures - giving reef sharks hope for the future.