Despite more than a decade of international efforts to curb the trade of threatened shark species, new research led by scientists from Florida International University and Dr. Demian Chapman, project leader and Director of the Shark and Rays Conservation Research Program at Mote Marine Laboratory & Aquarium, reveals that there is massive and sustained illegal trade of shark fins occurring from many countries worldwide.
The peer-reviewed study, published in Science Advances, shows that fins from four out of five shark species regulated under the Convention on International Trade of Endangered Species (CITES) remain common in Hong Kong’s markets, the global hub for shark fins, even though little to no legal trade has been reported since trade regulations took effect in 2014.
“Many sharks may be headed toward extinction, with international trade of shark products, such as dried fins that are used in the expensive luxury dish shark fin soup, often driving fishing pressure beyond species ability to reproduce and replenish populations,” said Dr. Chapman.
In 2013 countries recognized the severity of this problem and at a global meeting of members of the Convention on International Trade in Endangered Species (CITES) decided to impose trade regulations on five particularly threatened shark species that were important in trade — three large species of hammerheads (scalloped, smooth and great), the porbeagle and the oceanic whitetip. These regulations required that all trade be reported and certified as not threatening the species’ survival.
“Since the 2014 listings of these species on CITES, very little trade has been reported and certified, which makes a great deal of sense because of how poorly they are doing in the wild,” said Dr. Chapman. “Given these numbers, we would expect to find very few of their fins in Hong Kong.”
“Our findings show that while global trade regulations are a powerful tool, their effectiveness depends on countries actually enforcing them,” said Dr. Chapman. “We’re seeing clear evidence of widespread noncompliance, illegal trade is still happening on a massive scale.”
The study examined trade records and performed extensive DNA analyses on nearly 20,000 shark fin samples collected from Hong Kong markets between 2014 and 2021. Despite very low levels of legal trade, researchers found fins from scalloped, smooth and great hammerheads (Sphyrna lewini, S. zygaena, S. mokarran) and oceanic whitetip sharks (Carcharhinus longimanus) were commonly found year after year.
These species were added to CITES Appendix II in 2013, meaning that international trade of these species is only permitted if it is legal, traceable and sustainable. Yet 81% of shark-fin-exporting countries have never reported any trade in these listed species, suggesting illegal exports are ongoing.
“There’s a huge gap between what’s on paper and what’s happening in the real world,” said Dr. Diego Cardeñosa, lead author from Florida International University’s Department of Biological Sciences. “DNA evidence clearly shows these protected species are still entering the global market at alarming rates. There are 70 times more fins from oceanic whitetips and 10 times as many hammerhead fins than would be expected based on legal and certified reporting.”
Hammerhead and oceanic whitetip sharks are considered either Critically Endangered or Vulnerable by the IUCN Red List, and their ongoing exploitation threatens to push populations even closer to collapse. Using ‘DNA zip-coding,’ the team traced the origins of scalloped hammerhead fins sold in Hong Kong to 6 ocean regions, including the Indian, Eastern Pacific and South Atlantic, 3 of which had no legal export records of these species. This genetic tracking reveals that illegal trade spans continents and involves many major fishing nations.
“Genetics allows us to connect the dots between fishing grounds and market stalls,” said Dr. Chapman. “It’s one of the most powerful tools we have to identify where enforcement is failing.”
The team red-flagged several countries that are very likely involved in the illegal shark fin trade at a high level, including Spain, Taiwan, the United Arab Emirates, China, Philippines, Ghana and Brazil.
“We are reaching a major tipping point where if the fishing and trade of these species is not meaningfully reduced, then these sharks will disappear,” said Cardenosa. “This would be a huge loss of top predators in our oceans, which could unleash serious and unpredictable ecosystem changes that negatively affect us.”
Yet the research team remains hopeful. The study’s authors call for stronger efforts to engage CITES compliance mechanisms, greater enforcement and transparency in the trade and expanded genetic monitoring along supply chains.
“Shedding light on this problem is a major step toward solving it,” concluded Chapman. “CITES has internal compliance mechanisms to deal with illegal trade and in early December they will also decide whether to ban global trade in one of these species, the oceanic whitetip. We are at the point where these more stringent actions are needed.”
Mote’s Sharks & Rays Conservation Research Program continues to collaborate globally to improve understanding of shark biology, ecology and management, working toward a sustainable future for these keystone species and the ecosystems they support.
“Protecting sharks means protecting our oceans,” Dr. Chapman added. “Science-driven collaboration like this is exactly what it takes to turn the tide.”
The study also reinforces Florida International University’s (FIU) leadership in marine
conservation and wildlife forensics. As part of its institutional mission, FIU promotes research and action to end destructive fishing and illegal exploitation of marine species. A researcher in FIU’s Global Forensic and Justice Center and Institute of Environment, Dr. Cardeñosa earned global recognition for his work deploying DNA detection technology at ports and enabling law-enforcement agencies to prosecute wildlife-trafficking cases. With the current study, FIU further reinforces its global commitment to translating rigorous science into actionable conservation outcomes.
The full study, titled International trade regulations take a limited bite out of the shark fin trade, is available in Science Advances at https://www.science.org/doi/10.1126/sciadv.adz2821
