Outcomes, challenges and novel enforcement solutions following the 2004 cites appendix II listing of the humphead (=napoleon) wrasse, Cheilinus undulatus (order Perciformes; family Labridae)

Abstract

Humphead (=Napoleon) wrasse, Cheilinus undulatus, is one of the top-priced internationally traded live reef food fish predominantly destined for consumers in Mainland China, Hong Kong and other Chinese communities. High economic incentives have driven serious overfishing of the species which, in 2004, was listed as Endangered on the IUCN Red List, and added to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) Appendix II to avoid utilization incompatible with its survival. Hong Kong, as a signatory party of CITES and global trade hub for the species, must implement appropriate trade management and enforcement measures for its sustainable trade. This study assesses trade patterns in the species following its CITES-listing, into and through Hong Kong, evaluates enforcement effectiveness in the city, looks at outcomes for wild populations in Indonesia, the key exporter since 2010, and develops novel solutions to address implementation shortcomings detected, and enhance research capacity and education. Trade statistics of live humphead wrasse into and through Hong Kong were compiled from government databases (1999 to 2020) and market surveys (2014 to 2020) to describe trade patterns by volume and providence. Illegal, unregulated and undocumented trade was detected in local markets where numbers surveyed exceeded legal imports over multiple years. The current inability to distinguish legal from illegally traded fish compromises effective enforcement of the CITES listing thus requiring actions to solve the problem. Photo identification using artificial intelligence applied to the complex facial markings of humphead wrasse was explored as a potential solution to individual recognition to aid enforcement and for its research and educational potential. As proof-of-concept, tracking of unique facial markings of captive humphead wrasse revealed that patterns were unchanged for at least 2.5 years and confirmed that visually conducted comparisons could reliably distinguish among individuals over extended periods. To facilitate implementation for enforcement by the Agriculture, Fisheries and Conservation Department (AFCD), management authority of CITES in Hong Kong, encourage public participation in trade monitoring, and enhance education and research capability for the species a prototype phone application system, Saving Face, was developed. Since 2018, ranch-sourced humphead wrasse were exported from Indonesia in addition to wild-sourced fish. The inability to distinguish wild fish from ranched fish, which are more loosely managed in the trade but exported in higher numbers, is a further challenge for enforcement. Stable isotopes were assessed to determine δ13C and δ15N diet turnover rates and differences between ranched and wild fish. While the study was inconclusive, signatures were documented and could be tested for periods longer than the 212 days of this study. Tagging is recommended to distinguish between ranched and wild fish for enforcement purposes in the absence of any other method. Loopholes in trade management by both Hong Kong and Indonesia could be addressed by adoption and/or adaptation of the tools developed. Due to the COVID-19 pandemic, the trade in the species was severely limited in 2020 and 2021 severely limiting available sample sizes/replicates and much reduced the scale of possible experiments.