Development and application of a novel real-time polymerase chain reaction assay to detect illegal trade of the European eel (Anguilla anguilla)

In 2007, the critically endangered European eel (Anguilla anguilla) was listed in Appendix II of the Convention on International Trade in Endangered Species of Wild Flora and Fauna, due to declines in abundance across its range and significant international demand. Illegal trade in live European eel and its products is still occurring to satisfy the high demand around the world. Law enforcement officers face the challenge of identifying both live and processed European eel in a timely fashion to detain shipments and prosecute smugglers. Here, we describe the development of a reliable, field-based, fast, and cost-effective real-time polymerase chain reaction assay to detect European eels in trade. This novel assay was applied in a real law enforcement scenario, where positive results provided enough evidence to detain the shipment for more robust forensic analysis, leading to the first prosecution of eel smuggling in Hong Kong. Our approach could serve as a model for the development of other rapid and cost-effective tools to detect illegal wildlife trade where visual identification fails to provide enough evidence for prosecution. It could also enhance monitoring and enforcement of laws intended to protect highly traded and threatened species.