Every year, thousands of shark and ray fins are smuggled across international borders, hidden in plain sight in shipping containers or mislabeled among other cargo. For authorities tasked with stopping illegal wildlife trade, determining what's inside those shipments has long been nearly impossible — until now.
A breakthrough DNA-recognition tool developed by FIU marine biologist Diego Cardeñosa could change that, giving law enforcement the power to identify protected species on the spot and catch traffickers in the act. Cardeñosa conducts his research as part of FIU's Global Forensic and Justic Center and the Institute of Environment. Designed for field use rather than a lab, his portable and cost-effective device gives officers a critical advantage in fighting wildlife crime — one of the most lucrative forms of illegal activity in the world, worth an estimated $20 billion a year. Analyzing a tiny tissue sample, Cardeñosa tested 55 shark and ray species, including 38 protected under CITES, the international treaty that regulates trade to protect species from extinction.
For someone who has dedicated his life and career to protecting these endangered animals, the new device is another front in that battle. It builds on a previous "DNA toolkit" Cardeñosa's team developed in 2018, which could identify nine of the 12 species protected under CITES at the time. Today, the list has grown to 149 species, accounting for 68% of the global fin trade. Now, the device can even flag unknown species not in the database, giving authorities a way to catch unexpected or illegal shipments before it's too late.
"A lot of the law enforcement that we've worked with in the past say that if they cannot have preliminary evidence within 24 hours, they have to let the container go," Cardeñosa said. "If that first layer of proof is gone, then everything else falls."
With fins arriving dried, frozen, preserved in alcohol or even processed into shark fin soup, officers are often left guessing — a nearly impossible task when the clock is ticking.
"If we don't have that data, then all the effort we're putting into creating international laws is wasted," he said.
Since the 1970s, shark populations have plummeted by roughly 70%, driven largely by overfishing and the cruel practice of finning, in which sharks are stripped of their fins and discarded at sea, leaving them unable to swim or breathe. Slow-growing and producing few offspring, many shark species are highly vulnerable, with at least 30 now on the brink of extinction. Rays, too, face similar threats, with many species targeted for the growing international fin trade.
He hopes to deploy the device widely — from Sri Lanka and Indonesia to Ecuador, Peru, Mexico, Costa Rica and Brazil — to reduce overfishing and make it more difficult to profit from illegal fins in the future.
"That's the whole point, trying to create a deterrent so people won't do it," he said. "Then, because of that, we can start to see a change on the other side of the supply chain."
Cardeñosa stresses the importance of funding to expand the tool's international reach.
"We need to start combating illegal wildlife trade and take it seriously and support these kinds of initiatives, so they don't end up being only a scientific effort," he said.
Beyond sharks and rays, the device could also help protect broader wildlife.
"We are now trying to adapt it to turtles and mammals," he added, signaling a future where this technology could help curb illegal trade across multiple species worldwide.
For Cardeñosa, every fin identified represents more than a scientific breakthrough, but a step toward safeguarding ecosystems teetering on the edge of collapse. He credits supporters Paul G. Allen Philanthropies, Wildlife Conservation Society, Gallifrey Foundation and the National Science Foundation for helping make the research possible.
