Invertebrates comprise the majority of biodiversity in the oceans. The conservation issues facing these taxa, comprising c. 200,000 described and many more undescribed species, are diverse. The under-representation of marine invertebrates assessed for the IUCN Red List of Threatened Species will be addressed with a new Marine Invertebrate Red List Authority, formed in December 2022.

Comprising > 170 Specialist Groups, Red List Authorities and Task Forces, the IUCN Species Survival Commission (SSC) currently has only three groups focused solely on assessment and conservation of marine invertebrates: horseshoe crabs, corals and sea cucumbers. The SSC Marine Conservation Committee is currently preparing a proposal for a group focused on sea, brittle and feather stars. The remit of the Mollusc Specialist Group includes marine species, and although it has been assessing cephalopods, cone snails, abalone and some deep-sea species, it has mainly focused on terrestrial and freshwater species. All other marine invertebrates now have a home in the remit of the new Marine Invertebrate Red List Authority, which will work in collaboration with existing SSC groups and Centres for Species Survival to prioritize and assess taxa for the Red List, and develop additional specialist group capacity.

The geographical scope of the new Authority is global. Fisheries worldwide exert both direct and indirect pressure on marine invertebrate species and their habitats. There was a six-fold increase in landings and a doubling of the taxa reported in marine invertebrate fisheries from 1950 to 2010. Climate change, rising ocean temperatures and ocean acidification affect many marine invertebrates, particularly hard corals and species that grow or use shells and hard carapaces of calcium carbonate. Coastal development, infilling, dredging and deep-sea mining lead to direct mortality or habitat destruction. Offshore infrastructure and energy developments also affect invertebrates and their habitats. The impacts of such threats on the extinction risk of marine invertebrates are poorly known, particularly for less well-known taxa, such as those in the deep sea. Increasing public attention on the recent UN High Seas Treaty—which covers biodiversity in the vast areas of ocean beyond the jurisdiction of any country—and the threat of deep-sea mining, shows that assessment is urgently needed, to make a strong case to manage the deep sea appropriately for the protection of marine species.

The Marine Invertebrate Red List Authority will focus on the Red List assessment of marine invertebrate species, to shed light on threats and the level of extinction risk. This work is possible now because of generous funding for the Senckenberg Ocean Species Alliance, which will hire two full-time positions to work with the new Authority in 2023.