To conserve marine biodiversity, the spatial distribution and status of at-risk biodiversity must be well understood.

This study combined range maps and conservation status for 5.291 marine species to map the global distribution of extinction risk of marine biodiversity.

The obtained results provide a detailed spatial understanding of the distribution of conservation status of global marine diversity. It is shown that for 83% of the ocean, >25% of assessed species are considered threatened, and 15% of the ocean shows >50% of assessed species threatened when weighting for range-limited species.

Additionally, the authors compared the mean extinction risk of marine biodiversity to no-take marine reserve placement and identified regions where reserves preferentially afford proactive protection (i.e., preserving low-risk areas) or reactive protection (i.e., mitigating high-risk areas), indicating opportunities and needs for effective future protection at national and regional scales.

It is underlined as well that elevated risk to high seas biodiversity highlights the need for credible protection and minimization of threatening activities in international waters.

O’Hara et al. (2019) Mapping status and conservation of global at-risk marine biodiversity. Conservation Letters e12651.