Testing the presence of marine protected areas against their ability to reduce pressures on biodiversity.

Marine protected areas (MPAs) are the preferred tool for preventing marine biodiversity loss, as reflected in international protected area targets. Although the area covered by MPAs is expanding, there is a concern that opposition from resource users is driving them into already low-use locations, whereas high-pressure areas remain unprotected, which has serious implications for biodiversity conservation. We tested the spatial relationships between different human-induced pressures on marine biodiversity and global MPAs. We used global, modeled pressure data and the World Database on Protected Areas to calculate the levels of 15 different human-induced pressures inside and outside the world's MPAs. We fitted binomial generalized linear models to the data to determine whether each pressure had a positive or negative effect on the likelihood of an area being protected and whether this effect changed with different categories of protection. Pelagic and artisanal fishing, shipping, and introductions of invasive species by ships had a negative relationship with protection, and this relationship persisted under even the least restrictive categories of protection (e.g., protected areas classified as category VI under the International Union for Conservation of Nature, a category that permits sustainable use). In contrast, pressures from dispersed, diffusive sources (e.g., pollution and ocean acidification) had positive relationships with protection. Our results showed that MPAs are systematically established in areas where there is low political opposition, limiting the capacity of existing MPAs to manage key drivers of biodiversity loss. We suggest that conservation efforts focus on biodiversity outcomes and effective reduction of pressures rather than prescribing area-based targets, and that alternative approaches to conservation are needed in areas where protection is not feasible.

Evaluación de la Presencia de Áreas Marinas Protegidas contra sus Capacidades de Reducir las Presiones sobre la Biodiversidad Resumen Las áreas marinas protegidas (AMPs) son la herramienta preferida para prevenir la pérdida de biodiversidad marina, como se ve reflejado en los objetivos internacionales para las áreas protegidas. Mientras que el área que ocupan las MPAs está expandiéndose, existe una preocupación de que la oposición de los usuarios de recursos los esté llevando hacia localidades que ya son de bajo uso mientras que las áreas de alta presión permanecen sin protección, lo que tiene implicaciones serias para la conservación de la biodiversidad. Analizamos las relaciones espaciales entre diferentes presiones inducidas por humanos sobre la biodiversidad marina y las áreas marinas protegidas del mundo. Utilizamos datos mundiales de presiones modeladas y la Base de Datos de Áreas Protegidas para calcular los niveles de 15 diferentes presiones inducidas por humanos dentro y fuera de las MPAs del mundo. Ajustamos los modelos lineales binomiales y generalizados a los datos para determinar si cada una de las presiones tenía un efecto positivo o negativo sobre la probabilidad de que un área estuviera protegida y si este efecto cambió con diferentes categorías de protección. La pesca pelágica y artesanal, las embarcaciones, y la introducción de especies invasoras por parte de los barcos tuvieron una relación negativa con la protección y esta relación persistió incluso bajo las categorías más restrictivas de protección (es decir, áreas protegidas clasificadas bajo la categoría VI de la Unión Internacional para la Conservación de la Naturaleza, una categoría que permite el uso sostenible). Como contraste, las presiones surgidas de fuentes dispersadas y difusivas (por ejemplo, la contaminación y la acidificación del océano) tuvieron relaciones positivas con la protección. Nuestros resultados muestran que las MPAs están establecidas sistemáticamente en áreas en donde hay una baja oposición política, lo que limita la capacidad de las MPAs existentes para manejar los causantes más importantes de la pérdida de la biodiversidad. Sugerimos que los esfuerzos de conservación se enfoquen en los resultados de biodiversidad y en la reducción efectiva de las presiones en lugar de ordenar objetivos basados en el área y que se necesitan estrategias alternativas a la conservación en áreas en donde la protección no es viable.

Contrasting processes drive ophiuroid phylodiversity across shallow and deep seafloors.

Our knowledge of the distribution and evolution of deep-sea life is limited, impeding our ability to identify priority areas for conservation1. Here we analyse large integrated phylogenomic and distributional datasets of seafloor fauna from the sea surface to the abyss and from equator to pole of the Southern Hemisphere for an entire class of invertebrates (Ophiuroidea). We find that latitudinal diversity gradients are assembled through contrasting evolutionary processes for shallow (0-200 m) and deep (>200 m) seas. The shallow-water tropical-temperate realm broadly reflects a tropical diversification-driven process that shows exchange of lineages in both directions. Diversification rates are reversed for the realm that contains the deep sea and Antarctica; the diversification rates are highest at polar and lowest at tropical latitudes, and net exchange occurs from high to low latitudes. The tropical upper bathyal (200-700 m deep), with its rich ancient phylodiversity, is characterized by relatively low diversification and moderate immigration rates. Conversely, the young, specialized Antarctic fauna is inferred to be rebounding from regional extinctions that are associated with the rapid cooling of polar waters during the mid-Cenozoic era.

Scenarios and Models to Support Global Conservation Targets.

Global biodiversity targets have far-reaching implications for nature conservation worldwide. Scenarios and models hold unfulfilled promise for ensuring such targets are well founded and implemented; here, we review how they can and should inform the Aichi Targets of the Strategic Plan for Biodiversity and their reformulation. They offer two clear benefits: providing a scientific basis for the wording and quantitative elements of targets; and identifying synergies and trade-offs by accounting for interactions between targets and the actions needed to achieve them. The capacity of scenarios and models to address complexity makes them invaluable for developing meaningful targets and policy, and improving conservation outcomes.

Deep-sea diversity patterns are shaped by energy availability.

The deep ocean is the largest and least-explored ecosystem on Earth, and a uniquely energy-poor environment. The distribution, drivers and origins of deep-sea biodiversity remain unknown at global scales. Here we analyse a database of more than 165,000 distribution records of Ophiuroidea (brittle stars), a dominant component of sea-floor fauna, and find patterns of biodiversity unlike known terrestrial or coastal marine realms. Both patterns and environmental predictors of deep-sea (2,000-6,500 m) species richness fundamentally differ from those found in coastal (0-20 m), continental shelf (20-200 m), and upper-slope (200-2,000 m) waters. Continental shelf to upper-slope richness consistently peaks in tropical Indo-west Pacific and Caribbean (0-30°) latitudes, and is well explained by variations in water temperature. In contrast, deep-sea species show maximum richness at higher latitudes (30-50°), concentrated in areas of high carbon export flux and regions close to continental margins. We reconcile this structuring of oceanic biodiversity using a species-energy framework, with kinetic energy predicting shallow-water richness, while chemical energy (export productivity) and proximity to slope habitats drive deep-sea diversity. Our findings provide a global baseline for conservation efforts across the sea floor, and demonstrate that deep-sea ecosystems show a biodiversity pattern consistent with ecological theory, despite being different from other planetary-scale habitats.