Setting priorities for the conservation of marine vertebrates in Brazilian waters

• We analyzed three conservation-planning scenarios for Brazilian marine vertebrates.
• We compared conservation benefits provided by areas selected under each scenario.
• Avoiding areas of oil/gas exploitation caused only a small loss in conservation benefits.
• Southern Brazil and the Trindade–Martin Vaz insular complex were consistently prioritized for conservation.

The global panorama of biodiversity loss has motivated international agreements to enhance the protection of the oceans. Given the conflicting interests arising from multiple uses of seascapes and finite funds for conservation, developing cost-effective strategies for marine biodiversity conservation is crucial to support decision making. Here, we identified sites in Brazilian waters that would maximize species representation and avoid potential conflicts with relevant economic activities. We compared conservation benefits provided by three conservation-planning scenarios that incorporated the distribution of 750 marine vertebrate species, while considering established marine protected areas (MPAs) and blocks concessioned for the oil and gas industry. The results showed that a MPA network encompassing 10% of the study area with high conservation priority would cover between 85.8 and 86.5% of species distributions, on average. We found that incorporating existing MPAs and areas concessioned for oil and gas exploitation in the prioritization process caused only a small loss in representation of near-threatened and threatened species. Our results highlight, therefore, that it is possible to reconcile current offshore oil and gas production with the expansion of the national MPA network, without significant losses in species' representation. These results represent a preliminary assessment of spatial priorities for conservation of marine vertebrates in Brazilian waters. They can be used to prompt a dialog with social actors, in order to expand the national MPA system.