Talk about a conservation win: sharks in the Atlantic ocean may have a fighting chance!
Florida International University postdoc Dr. Diego Cardeñosa has been leading a new study using DNA to track where fins in the global shark fin trade come from. In collaboration with scientists in Hong Kong, the team has been focusing on silky sharks (Carcharhinus falciformis) – the second most common species found in the fin trade.“Understanding which species are most prevalent in the shark fin trade can help identify the species in need of conservation intervention,” Cardeñosa said. “Tracing the populations of origin can help identify the key management jurisdictions that can lead proper interventions.”
The research, which is supported by the Pew Charitable Trusts and the Pew Fellowship Program, found that 99.8% of the fins sampled from retail markets in Hong Kong and China originated from the Indo-Pacific Ocean. That means virtually none came from the Atlantic Ocean – the first evidence that conservation efforts could be making an impact in this region!
Silky sharks are an oceanic and coastal-pelagic shark found globally in tropical waters. A high proportion of pelagic sharks, like silky sharks, are overexploited due to coming in constant contact with fishing fleets targeting tuna (especially by purse seines on drifting fish aggregating devices, or FADs). The constant demand for their fins in Asia has incentivized the retention of these ostensibly “bycatch” animals, meaning none of these predators are safe. The fact that silky sharks have been identified as the second most common species in the shark fin trade for the last two decades means that there are consistently high landings of this species. This is concerning because they are listed as “Vulnerable” by the International Union for Conservation of Nature (IUCN) and are listed as a pelagic species most vulnerable to overexploitation.
So how can one protect an animal that is distributed worldwide? With the help of international organizations that carry out data collection, scientific monitoring, and management regarding oceanic resources, like sharks. Silky shark management actually falls under the purview of four of the five existing tuna Regional Fisheries Management Organizations (RFMOs). In 2011 one of these RFMOs, the International Commission for the Conservation of Atlantic Tuna (ICCAT), prohibited the fishing, retention, and transshipment of silky sharks by all fisheries operating under its jurisdiction. Silky sharks are protected under Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), an agreement that fights against this shark’s overexploitation in international trade. Listed in Appendix II, all trade of these sharks requires permits certifying they were legally caught, catch is sustainable, and traceable through the supply chain.
This latest data shows that there’s high compliance with the retention and export ban! “This study shows that there is good news for ICCAT and the Atlantic silkies,” said Cardeñosa. “While it doesn’t necessarily mean that the Atlantic population is recovering or that fishing mortality is decreasing, it’s a good assessment that there’s high compliance with the retention and export ban by ICCAT parties.”
But unfortunately, the reality is that illegal, unreported trade continues to happen worldwide. In fact, earlier this year Hong Kong intercepted an illegal shipment from Ecuador that included silky and pelagic thresher shark fins! Cardeñosa is just getting started, hoping his work can help pinpoint where shark fins originate in order to better direct shark conservation efforts and fisheries management. But for now… he and his colleagues will take this win as a step in the right direction.