UW Aquatic & Fishery Sciences Quantitative Seminar
UW Aquatic & Fishery Sciences
Estimating sustainable export levels for an endangered coral reef fish: The example of the humphead wrasse
co-authors: Yvonne Sadovy, William Cheung, & Marcelo Vasconcellos
The humphead wrasse (or Napolean fish), Cheilinus undulatus, was the first coral reef fish to be listed on CITES Appendix II. Under CITES regulations, countries exporting Appendix II species are required to demonstrate that the export quotas are derived from legal fisheries and that such exports will not be detrimental to the survival of the species and to its role in the ecosystem. A tool is outlined for determining sustainable catch levels of the species in Indonesia. The approach is composed of a population model and a method for estimating stock density based on Underwater Visual Surveys, and allows for the representation of "grow out" of net-caged animals, the ability to account for uncertainty in most of the parameters of the model, and the ability to compute a sustainable catch (and its associated uncertainty) corresponding to a user-specified level of fishing mortality.