Evaluating Species at Risk in Data-Limited Fisheries: A Comprehensive Productivity-Susceptibility Analysis of the Most Traded Marine Aquarium Fish

The marine aquarium trade is a significant global industry harvesting millions of live coral reef fishes annually. Wild-caught fish dominate public and private aquaria markets in the USA and Europe, supporting fisher livelihoods in the Indo-Pacific. This diverse and species-rich trade is considered data-limited, creating barriers to quantify the sustainability of this fishery to the net benefit of the coral reef socio-ecological system. We present a revised and expanded productivity-susceptibility analysis (PSA) framework to assess the vulnerability to overharvesting of the top 258 traded species, an estimated 92.5% of all import volume into the USA in 2011. Vulnerability was calculated based on various productivity and susceptibility factors, tailored to the unique life-history and fishery selectivity characteristics of the marine aquarium trade. We present novel factors that improve model accuracy, methods to overcome missing data for individual factors, and apply an improved Gaussian mixture model clustering algorithm to objectively classify species as least, moderately, or most vulnerable. Our results show that an overwhelming 85% of species evaluated fall into the least or moderately vulnerable classification, with the remaining species designated as high priority for localized assessment and management initiatives. A comparative case study between our PSA and the popular FishBase Vulnerability assessment illustrates how it is ill-suited to handle data limitations of non-food fishes. The results of our PSA, at a species and family level, provide useful information to stakeholders and serves as a robust and accessible risk assessment tool to prioritize species for management based on their vulnerability scores. ### Competing Interest Statement Gabrielle A. Baillargeon is funded by UKRI under a NERC Panorama Doctoral Training Program scholarship at the University of Leeds. CASE partners on this scholarship include: Ornamental Aquatic Trade Association (OATA), Center for Environment, Fisheries, and Aquaculture Science (Cefas), and Mars Inc. The data and statements made herein are exclusively the authors and do not necessarily reflect that of funding partners. Jemelyn Grace Baldisimo (JGB) collaborated on this study as part of her Virginia Sea Grant Graduate Student Fellowship. JGB is a member of the Philippine Aquatic Red List Marine Ornamentals Committee and IUCN Species Survival Commission. The views expressed in this publication do not necessarily reflect those of IUCN. The designation of geographical entities in this paper, and the presentation of the material, do not imply the expression of any opinion whatsoever on the part of IUCN concerning the legal status of any country, territory, or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. Michael F. Tlusty advises governments on improving wildlife trade data. Andrew L. Rhyne: Advises public aquaria on the sustainability of living collections and has formal agreements with aquaria concerning aquaculture production of fish species for display. His laboratory specializes in the production of aquarium fish for the trade. Moreover, he has received funding from pet industry groups and non-governmental organizations (NGOs) interested in restoration aquaculture, reduction in cyanide fishing, and animal welfare. Rhyne also co-developed a wildlife trade platform that is currently being tested by a national government as an implementation solution to increase the granularity of wildlife trade data. These relationships could be seen to influence the research presented, although every effort has been made to ensure they have not. The statements made herein are solely the responsibility of the authors.