New framework reveals gaps in US ocean biodiversity protection

Human activities threaten Earth’s biodiversity and its contributions to human well-being. In the ocean, our poor understanding of how biodiversity is distributed limits its management and protection, necessitating reliance on weak abiotic proxies. Here, we propose a scientific framework for assessing marine biodiversity at multiple spatial scales, which exposes gaps in biodiversity knowledge and protection. The framework prioritizes ecologically and societally important taxa, characteristics of effective networks, and existing data. Applying the framework to assess biodiversity inside and outside US marine protected areas, we reveal that these areas contain a fraction of the biodiversity found in US waters. We show that none of the nation’s 24 marine ecoregions meet all criteria for an effective protection network and that biodiversity coverage in protected areas varies among regions and taxa. This marine biodiversity assessment highlights concrete recommendations for more strategic protection and validates a scientific framework generalizable to other spatial management uses.