Assessing the conservation potential of fish and corals in aquariums globally

Aquatic ecosystems are indispensable for life on earth and yet despite their essential function and service roles, marine and freshwater biomes are facing unprecedented threats from both traditional and emerging anthropogenic stressors. The resultant species and ecosystem-level threat severity requires an urgent response from the conservation community. With their care facilities, veterinary and conservation breeding expertise, reintroduction and restoration, and public communication reach, stand-alone aquariums and zoos holding aquatic taxa have great collective potential to help address the current biodiversity crisis, which is now greater in freshwater than land habitats. However, uncertainty regarding the number of species kept in such facilities hinders assessment of their conservation value. Here we analyzed, standardized and shared data of zoological institution members of Species360, for fish and Anthozoa species (i.e. Actinopterygii, Elasmobranchii, Holocephali, Myxini, Sarcopterygii and Anthozoa). To assess the conservation potential of populations held in these institutions, we cross-referenced the Species360 records with the following conservation schemes: the Convention on the International Trade of Endangered Species of Fauna and Flora (CITES), the IUCN Red List of Threatened species, climate change vulnerability, Evolutionary Distinct and Globally Endangered (EDGE) and The Alliance for Zero Extinction (AZE). We found that aquariums hold four of the six fish species listed by the IUCN Red List as ‘Extinct in the Wild’, 31% of Anthozoa species listed by Foden et al. (2013) as vulnerable to climate change, 19 out of the 111 Anthozoa EDGE species, and none of the species prioritized by the AZE. However, it is very likely that significant additional species of high conservation value are held in aquariums that do not manage their records in standardized, sharable platforms such as Species360. Our study highlights both the great value of aquarium and zoo collections for addressing the aquatic biodiversity crisis, as well as the importance that they maintain comprehensive, standardised, globally-shared taxonomic data.