Evaluating ecological benefits of oceanic protected areas

The ratification of the United Nations High Seas Treaty will help protect overlooked oceanic ecosystems, leading to an expected large increase in the declaration of oceanic (defined here as waters >200 m in depth) Marine Protected Areas (oMPAs) in the current decade. In many places this will need to be done in cooperation with existing sectoral management bodies.Despite this likely expansion, our current understanding of the ecological benefits of oMPAs is derived primarily from coastal protected areas, which are shallower, generally well mixed, and face different threats than oMPAs. Consequently, the strong scientific consensus for the ecological benefits of coastal MPAs is lacking for oMPAs.Emerging new sampling platforms and methods can help address this gap and inform the design and placement of new oMPAs that aim to conserve both pelagic and benthic biodiversity. Oceans beyond the continental shelf represent the largest yet least protected environments. The new agreement to increase protection targets to 30% by 2030 and the recent United Nations (UN) High Seas Treaty try to address this gap, and an increase in the declaration of oceanic Marine Protected Areas (oMPAs) in waters beyond 200 m in depth is likely. Here we find that there is contradictory evidence concerning the benefits of oMPAs in terms of protecting pelagic habitats, providing refuge for highly mobile species, and potential fisheries benefits. We discover a mismatch between oMPA management objectives focusing on protection of pelagic habitats and biodiversity, and scientific research focusing on fisheries benefits. We suggest that the solution is to harness emerging technologies to monitor inside and outside oMPAs. Oceans beyond the continental shelf represent the largest yet least protected environments. The new agreement to increase protection targets to 30% by 2030 and the recent United Nations (UN) High Seas Treaty try to address this gap, and an increase in the declaration of oceanic Marine Protected Areas (oMPAs) in waters beyond 200 m in depth is likely. Here we find that there is contradictory evidence concerning the benefits of oMPAs in terms of protecting pelagic habitats, providing refuge for highly mobile species, and potential fisheries benefits. We discover a mismatch between oMPA management objectives focusing on protection of pelagic habitats and biodiversity, and scientific research focusing on fisheries benefits. We suggest that the solution is to harness emerging techn