Abstract
International trade is a major driver of shark overexploitation. In 2013, five threatened shark species were listed on Appendix II of the Convention on International Trade of Endangered Species to regulate global trade and promote recovery. Once listed, any uncertified, unreported export of these species became illegal. Minimal trade was reported from 2015 to 2021, yet fins from four of these species were common in the world's largest shark fin hub (Hong Kong) throughout this period, indicating substantial and sustained illegal trade. Seventy three of 90 shark fin-exporting nations (81%) have never reported any trade of these species. Mixed stock analysis of a market sample of fins from one listed species revealed six populations of origin but only three were from regions where trade was reported. Broader application of CITES compliance mechanisms is necessary to combat widespread illegal trade of shark fins and realize the conservation potential of these trade regulations.