Ecological countermeasures to prevent pathogen spillover and subsequent pandemics.

Substantial global attention is focused on how to reduce the risk of future pandemics. Reducing this risk requires investment in prevention, preparedness, and response. Although preparedness and response have received significant focus, prevention, especially the prevention of zoonotic spillover, remains largely absent from global conversations. This oversight is due in part to the lack of a clear definition of prevention and lack of guidance on how to achieve it. To address this gap, we elucidate the mechanisms linking environmental change and zoonotic spillover using spillover of viruses from bats as a case study. We identify ecological interventions that can disrupt these spillover mechanisms and propose policy frameworks for their implementation. Recognizing that pandemics originate in ecological systems, we advocate for integrating ecological approaches alongside biomedical approaches in a comprehensive and balanced pandemic prevention strategy.

Conservation planning for retention, not just protection.

Most protected area (PA) planning aims to improve biota representation within the PA system, but this does not necessarily achieve the best outcomes for biota retention across regions when we also consider habitat loss in areas outside the PA system. Here, we assess the implications that different PA expansion strategies can have on the retention of species habitat across an entire region. Using retention of forest habitat for Colombia's 550 forest-dependent bird species as our outcome variable, we found that when a minimum of 30% of each species' habitat was included in the PA system, a pattern of PA expansion targeting areas at highest deforestation risk (risk-prevention) led to the retention, on average, of 7.2% more forest habitat per species by 2050 than did a pattern that targeted areas at lowest risk (risk-avoidance). The risk-prevention approach cost more per km2 of land conserved, but it was more cost-effective in retaining habitat in the landscape (50%-69% lower cost per km2 of avoided deforestation). To have the same effectiveness preventing habitat loss in Colombia, the risk-avoidance approach would require more than twice as much protected area, costing three times more in the process. Protected area expansion should focus on the contributions of PAs to outcomes not only within PA systems themselves, but across entire regions.

La mayor parte de la planificación de áreas protegidas (AP) tiene como objetivo mejorar la representación de la biota dentro del sistema de AP, pero esto no necesariamente logra los mejores resultados para la retención de biota a nivel de paisaje cuando también consideramos la pérdida de hábitat en áreas fuera del sistema de AP. Aquí evaluamos las implicaciones que diferentes estrategias de expansión de AP pueden tener en la retención del hábitat de las especies en toda una región. Utilizando la retención de hábitat forestal para las 550 especies de aves dependientes de bosque de Colombia como nuestra variable de resultado, encontramos que cuando un mínimo del 30% del hábitat de cada especie es incluido en el sistema de AP, se observó que un patrón de expansión de AP dirigido a áreas con mayor riesgo de deforestación (prevención de riesgos) condujo a la retención, en promedio, de un 7.2% más de hábitat por especie para 2050 que un patrón enfocado en áreas con menor riesgo (evasión de riesgos). El enfoque de prevención de riesgos costó más por km2 de tierra conservada, pero fue más rentable para retener el hábitat en el paisaje (entre un 50% y un 69% menos costo por km2 de deforestación evitada). Para tener la misma eficacia en la prevención de la pérdida de hábitat en Colombia, el enfoque de evasión de riesgos requeriría más del doble de área protegida, lo que costaría tres veces más en el proceso. La expansión de las AP debería centrarse en las contribuciones de las AP a los resultados no sólo dentro de los propios sistemas de AP, sino en regiones enteras.

Multiple invasive species affect germination, growth, and photosynthesis of native weeds and crops in experiments.

Alien plant species regularly and simultaneously invade agricultural landscapes and ecosystems; however, the effects of co-invasion on crop production and native biodiversity have rarely been studied. Secondary metabolites produced by alien plants may be allelopathic; if they enter the soil, they may be transported by agricultural activities, negatively affecting crop yield and biodiversity. It is unknown whether substances from different alien species in combination have a greater impact on crops and wild plants than if they are from only one of the alien species. In this study, we used a set of common garden experiments to test the hypothesis that mixed extracts from two common invasive species have synergistic effects on crops and weeds (defined as all non-crop plants) in European agricultural fields compared to single-species extracts. We found that both the combined and individual extracts had detrimental effects on the seed germination, seedling growth, biomass, and photosynthetic performance of both crops and weeds. We found that the negative effect of mixed extracts was not additive and that crop plants were more strongly affected by invasive species extracts than the weeds. Our results are important for managing invasive species in unique ecosystems on agricultural land and preventing economic losses in yield production.

Climate-driven variation in dispersal ability predicts responses to forest fragmentation in birds.

Species sensitivity to forest fragmentation varies latitudinally, peaking in the tropics. A prominent explanation for this pattern is that historical landscape disturbance at higher latitudes has removed fragmentation-sensitive species or promoted the evolution of more resilient survivors. However, it is unclear whether this so-called extinction filter is the dominant driver of geographic variation in fragmentation sensitivity, particularly because climatic factors may also cause latitudinal gradients in dispersal ability, a key trait mediating sensitivity to habitat fragmentation. Here we combine field survey data with a morphological proxy for avian dispersal ability (hand-wing index) to assess responses to forest fragmentation in 1,034 bird species worldwide. We find that fragmentation sensitivity is strongly predicted by dispersal limitation and that other factors-latitude, body mass and historical disturbance events-have relatively limited explanatory power after accounting for species differences in dispersal. We also show that variation in dispersal ability is only weakly predicted by historical disturbance and more strongly associated with intra-annual temperature fluctuations (seasonality). Our results suggest that climatic factors play a dominant role in driving global variation in the impacts of forest fragmentation, emphasizing the need for more nuanced environmental policies that take into account local context and associated species traits.

Beyond ecology: ecosystem restoration as a process for social-ecological transformation.

Ecosystem restoration conventionally focuses on ecological targets. However, while ecological targets are crucial to mobilizing political, social, and financial capital, they do not encapsulate the need to: integrate social, economic, and ecological dimensions and systems approaches; reconcile global targets and local objectives; and measure the rate of progress toward multiple and synergistic goals. Restoration is better conceived as an inclusive social-ecological process that integrates diverse values, practices, knowledge, and restoration objectives across temporal and spatial scales and stakeholder groups. Taking a more process-based approach will ultimately enable greater social-ecological transformation, greater restoration effectiveness, and more long-lasting benefits to people and nature across time and place.

Protected area planning to conserve biodiversity in an uncertain future.

Protected areas are a key instrument for conservation. Despite this, they are vulnerable to risks associated with weak governance, land-use intensification, and climate change. We used a novel hierarchical optimization approach to identify priority areas for expanding the global protected area system that explicitly accounted for such risks while maximizing protection of all known terrestrial vertebrate species. To incorporate risk categories, we built on the minimum set problem, where the objective is to reach species distribution protection targets while accounting for 1 constraint, such as land cost or area. We expanded this approach to include multiple objectives accounting for risk in the problem formulation by treating each risk layer as a separate objective in the problem formulation. Reducing exposure to these risks required expanding the area of the global protected area system by 1.6% while still meeting conservation targets. Incorporating risks from weak governance drove the greatest changes in spatial priorities for protection, and incorporating risks from climate change required the largest increase (2.52%) in global protected area. Conserving wide-ranging species required countries with relatively strong governance to protect more land when they bordered nations with comparatively weak governance. Our results underscore the need for cross-jurisdictional coordination and demonstrate how risk can be efficiently incorporated into conservation planning. Planeación de las áreas protegidas para conservar la biodiversidad en un futuro incierto.

Aunque las áreas protegidas son un instrumento clave para la conservación, no dejan de ser vulnerables a los riesgos asociados a una gestión pobre, la intensificación del uso de suelo y al cambio climático. Usamos una estrategia novedosa de optimización jerárquica para identificar las áreas prioritarias para la expansión del sistema global de áreas protegidas. La estrategia consideró de manera explícita los riesgos mencionados y también maximizó la protección de todas las especies conocidas de vertebrados terrestres. Para incorporar a las categorías de riesgo partimos del mínimo problema establecido, en donde el objetivo es lograr los objetivos de protección de la distribución de especies mientras se considera sólo una restricción, como el costo o área del suelo. Expandimos esta estrategia para que incluyera varios objetivos que consideraran el riesgo desde la formulación del problema mediante el manejo de cada nivel de riesgo como un objetivo aparte durante la formulación del problema. La reducción de la exposición a estos riesgos requirió que se expandiera el área total del sistema global de áreas protegidas en un 1.6% y así todavía cumplir con los objetivos de conservación. La incorporación de riesgos a partir de una gestión pobre fue el principal impulsor de cambios en las prioridades espaciales para la protección, mientras que la incorporación de riesgos a partir del cambio climático requirió el mayor incremento (2.52%) del área protegida a nivel mundial. La conservación de especies con distribución amplia requirió que los países con una gestión relativamente fuerte protegieran más suelo al tener fronteras con países con una gestión pobre en comparación son la suya. Nuestros resultados destacan la necesidad de una coordinación entre jurisdicciones y demuestran cómo puede incorporarse el riesgo de manera exitosa a la planeación de la conservación.

Effects of different management strategies on long-term trends of Australian threatened and near-threatened mammals.

Monitoring is critical to assess management effectiveness, but broadscale systematic assessments of monitoring to evaluate and improve recovery efforts are lacking. We compiled 1808 time series from 71 threatened and near-threatened terrestrial and volant mammal species and subspecies in Australia (48% of all threatened mammal taxa) to compare relative trends of populations subject to different management strategies. We adapted the Living Planet Index to develop the Threatened Species Index for Australian Mammals and track aggregate trends for all sampled threatened mammal populations and for small (<35 g), medium (35-5500 g), and large mammals (>5500 g) from 2000 to 2017. Unmanaged populations (42 taxa) declined by 63% on average; unmanaged small mammals exhibited the greatest declines (96%). Populations of 17 taxa in havens (islands and fenced areas that excluded or eliminated introduced red foxes [Vulpes vulpes] and domestic cats [Felis catus]) increased by 680%. Outside havens, populations undergoing sustained predator baiting initially declined by 75% but subsequently increased to 47% of their abundance in 2000. At sites where predators were not excluded or baited but other actions (e.g., fire management, introduced herbivore control) occurred, populations of small and medium mammals declined faster, but large mammals declined more slowly, than unmanaged populations. Only 13% of taxa had data for both unmanaged and managed populations; index comparisons for this subset showed that taxa with populations increasing inside havens declined outside havens but taxa with populations subject to predator baiting outside havens declined more slowly than populations with no management and then increased, whereas unmanaged populations continued to decline. More comprehensive and improved monitoring (particularly encompassing poorly represented management actions and taxonomic groups like bats and small mammals) is required to understand whether and where management has worked. Improved implementation of management for threats other than predation is critical to recover Australia's threatened mammals.

Efectos de diferentes estrategias de manejo sobre las tendencias a largo plazo de los mamíferos amenazados y casi amenazados de Australia Resumen El monitoreo es fundamental para evaluar la efectividad del manejo, aunque faltan evaluaciones sistemáticas y a gran escala de este monitoreo para evaluar y mejorar los esfuerzos de recuperación. Compilamos 1,808 series temporales de 71 especies y subespecies de mamíferos terrestres y voladores amenazadas y casi amenazadas en Australia (48% de todos los taxones de mamíferos amenazados) para comparar las tendencias relativas de las poblaciones sujetas a diferentes estrategias de manejo. Adaptamos el Índice Planeta Vivo para desarrollar el Índice de Especies Amenazadas para los Mamíferos Australianos y así rastrear las tendencias agregadas de todas las poblaciones muestreadas de mamíferos amenazados y de los mamíferos pequeños (<35 g), medianos (35-5,500 g) y grandes (>5,500 g) entre 2000 y 2017. Las poblaciones sin manejo (42 taxones) declinaron en un 63% en promedio; los mamíferos pequeños sin manejo exhibieron las declinaciones más marcadas (96%). Las poblaciones de 17 taxones incrementaron 680% en los refugios (islas o áreas encercadas que excluían o eliminaban al zorro rojo [Vulpes vulpes] y al gato doméstico [Felis catus], especies introducidas) Afuera de los refugios, las poblaciones sometidas al cebado constante de los depredadores en un inicio declinaron en un 75% pero después incrementaron al 47% de su abundancia para el 2000. En los sitios en donde los depredadores no fueron excluidos o cebados sino sometidos a otras acciones (manejo del fuego, control de herbívoros introducidos), las poblaciones de los mamíferos pequeños y medianos declinaron más rápido, pero los mamíferos grandes declinaron de manera más lenta que las poblaciones sin manejo. Sólo el 13% de los taxones contaron con datos para sus poblaciones con y sin manejo; las comparaciones entre índices para este subconjunto mostraron que los taxones con poblaciones en incremento dentro de los refugios declinaron afuera de éstos, pero los taxones con poblaciones sujetas al cebado de depredadores afuera de los refugios declinaron más lentamente que las poblaciones sin manejo y después incrementaron, mientras que las poblaciones sin manejo continuaron su declinación. Se requiere un monitoreo más completo y mejorado (particularmente el que engloba las acciones de manejo mal representadas y los grupos taxonómicos como los murciélagos y los mamíferos pequeños) para entender si ha funcionado el manejo y en dónde. La implementación mejorada del manejo para las amenazas distintas a la depredación es fundamental para recuperar a los mamíferos amenazados de Australia.

The role of incentive mechanisms in promoting forest restoration.

Forest restoration has been proposed as a scalable nature-based solution to achieve global environmental and socio-economic outcomes and is central to many policy initiatives, such as the Bonn Challenge. Restored forests contain appreciable biodiversity, improve habitat connectivity and sequester carbon. Incentive mechanisms (e.g. payments for ecosystem services and allocation of management rights) have been a focus of forest restoration efforts for decades. Yet, there is still little understanding of their role in promoting restoration success. We conducted a systematic literature review to investigate how incentive mechanisms are used to promote forest restoration, outcomes, and the biophysical and socio-economic factors that influence implementation and program success. We found that socio-economic factors, such as governance, monitoring systems and the experience and beliefs of participants, dominate whether or not an incentive mechanism is successful. We found that approximately half of the studies report both positive ecological and socio-economic outcomes. However, reported adverse outcomes were more commonly socio-economic than ecological. Our results reveal that achieving forest restoration at a sufficient scale to meet international commitments will require stronger assessment and management of socio-economic factors that enable or constrain the success of incentive mechanisms. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.

Threat management priorities for conserving Antarctic biodiversity.

Antarctic terrestrial biodiversity faces multiple threats, from invasive species to climate change. Yet no large-scale assessments of threat management strategies exist. Applying a structured participatory approach, we demonstrate that existing conservation efforts are insufficient in a changing world, estimating that 65% (at best 37%, at worst 97%) of native terrestrial taxa and land-associated seabirds are likely to decline by 2100 under current trajectories. Emperor penguins are identified as the most vulnerable taxon, followed by other seabirds and dry soil nematodes. We find that implementing 10 key threat management strategies in parallel, at an estimated present-day equivalent annual cost of US$23 million, could benefit up to 84% of Antarctic taxa. Climate change is identified as the most pervasive threat to Antarctic biodiversity and influencing global policy to effectively limit climate change is the most beneficial conservation strategy. However, minimising impacts of human activities and improved planning and management of new infrastructure projects are cost-effective and will help to minimise regional threats. Simultaneous global and regional efforts are critical to secure Antarctic biodiversity for future generations.

Demystifying ecological connectivity for actionable spatial conservation planning.

Connectivity underpins the persistence of life; it needs to inform biodiversity conservation decisions. Yet, when prioritising conservation areas and developing actions, connectivity is not being operationalised in spatial planning. The challenge is the translation of flows associated with connectivity into conservation objectives that lead to actions. Connectivity is nebulous, it can be abstract and mean different things to different people, making it difficult to include in conservation problems. Here, we show how connectivity can be included in mathematically defining conservation planning objectives. We provide a path forward for linking connectivity to high-level conservation goals, such as increasing species' persistence. We propose ways to design spatial management areas that gain biodiversity benefit from connectivity.

The minimum land area requiring conservation attention to safeguard biodiversity.

Ambitious conservation efforts are needed to stop the global biodiversity crisis. In this study, we estimate the minimum land area to secure important biodiversity areas, ecologically intact areas, and optimal locations for representation of species ranges and ecoregions. We discover that at least 64 million square kilometers (44% of terrestrial area) would require conservation attention (ranging from protected areas to land-use policies) to meet this goal. More than 1.8 billion people live on these lands, so responses that promote autonomy, self-determination, equity, and sustainable management for safeguarding biodiversity are essential. Spatially explicit land-use scenarios suggest that 1.3 million square kilometers of this land is at risk of being converted for intensive human land uses by 2030, which requires immediate attention. However, a sevenfold difference exists between the amount of habitat converted in optimistic and pessimistic land-use scenarios, highlighting an opportunity to avert this crisis. Appropriate targets in the Post-2020 Global Biodiversity Framework to encourage conservation of the identified land would contribute substantially to safeguarding biodiversity.

How to prioritize species recovery after a megafire.

Due to climate change, megafires are increasingly common and have sudden, extensive impacts on many species over vast areas, leaving decision makers uncertain about how best to prioritize recovery. We devised a decision-support framework to prioritize conservation actions to improve species outcomes immediately after a megafire. Complementary locations are selected to extend recovery actions across all fire-affected species' habitats. We applied our method to areas burned in the 2019-2020 Australian megafires and assessed its conservation advantages by comparing our results with outcomes of a site-richness approach (i.e., identifying areas that cost-effectively recover the most species in any one location). We found that 290 threatened species were likely severely affected and will require immediate conservation action to prevent population declines and possible extirpation. We identified 179 subregions, mostly in southeastern Australia, that are key locations to extend actions that benefit multiple species. Cost savings were over AU$300 million to reduce 95% of threats across all species. Our complementarity-based prioritization also spread postfire management actions across a wider proportion of the study area compared with the site-richness method (43% vs. 37% of the landscape managed, respectively) and put more of each species' range under management (average 90% vs. 79% of every species' habitat managed). In addition to wildfire response, our framework can be used to prioritize conservation actions that will best mitigate threats affecting species following other extreme environmental events (e.g., floods and drought).

Debido al cambio climático, los mega incendios son cada vez más comunes y tienen un impacto repentino y extenso sobre muchas especies en inmensas superficies, lo que deja a los tomadores de decisiones con incertidumbre sobre cuál es la mejor manera de priorizar la recuperación. Diseñamos un marco de apoyo a las decisiones para priorizar las acciones de conservación para mejorar los resultados para las especies inmediatamente después de un mega incendio. Para esto, se seleccionan localidades complementarias para extender las acciones de recuperación por todos los hábitats de las especies afectadas por el incendio. Aplicamos nuestro método a las áreas afectadas por los mega incendios de 2019-2020 en Australia y analizamos las ventajas de conservación del método mediante la comparación entre nuestros resultados y aquellos de un enfoque en la riqueza de especies (es decir, la identificación de las áreas que recuperan de manera rentable la mayor cantidad de especies en cualquier localidad única). Encontramos que 290 especies amenazadas estuvieron probablemente afectadas de manera severa y requerirán acciones inmediatas de conservación para prevenir la declinación poblacional y la posible eliminación. Identificamos 179 subregiones, la mayoría en el sureste de Australia, que son localidades clave para extender las acciones que benefician a muchas especies. El ahorro en los gastos fue de más de AU$300 millones para reducir el 95% de las amenazas para todas las especies. Nuestra priorización basada en la complementariedad también extendió las acciones de manejo posterior al incendio a una mayor proporción del área de estudio en comparación con el método de riqueza de especies (43% versus 37% del paisaje gestionado, respectivamente) y colocó más de la distribución de cada especie bajo manejo (en promedio 90% versus 79% del hábitat manejado de cada especie). Además de la respuesta a los incendios, nuestro marco puede usarse para priorizar las acciones de conservación que mitiguen de mejor manera las amenazas que afectan a las especies después de otros eventos ambientales extremos (p. ej., inundaciones y sequía).

Effectiveness of 20 years of conservation investments in protecting orangutans.

Conservation strategies are rarely systematically evaluated, which reduces transparency, hinders the cost-effective deployment of resources, and hides what works best in different contexts. Using data on the iconic and critically endangered orangutan (Pongo spp.), we developed a novel spatiotemporal framework for evaluating conservation investments. We show that around USD 1 billion was invested between 2000 and 2019 into orangutan conservation by governments, nongovernmental organizations, companies, and communities. Broken down by allocation to different conservation strategies, we find that habitat protection, patrolling, and public outreach had the greatest return on investment for maintaining orangutan populations. Given the variability in threats, land-use opportunity costs, and baseline remunerations in different regions, there were differential benefits per dollar invested across conservation activities and regions. We show that although challenging from a data and analysis perspective, it is possible to fully understand the relationships between conservation investments and outcomes and the external factors that influence these outcomes. Such analyses can provide improved guidance toward a more effective biodiversity conservation. Insights into the spatiotemporal interplays between the costs and benefits driving effectiveness can inform decisions about the most suitable orangutan conservation strategies for halting population declines. Although our study focuses on the three extant orangutan species of Sumatra and Borneo, our findings have broad application for evidence-based conservation science and practice worldwide.

Wilderness forms and their implications for global environmental policy and conservation.

With the intention of securing industry-free land and seascapes, protecting wilderness entered international policy as a formal target for the first time in the zero draft of the Post-2020 Global Biodiversity Framework under the Convention on Biological Diversity. Given this increased prominence in international policy, it is timely to consider the extent to which the construct of wilderness supports global conservation objectives. We evaluated the construct by overlaying recently updated cumulative human pressure maps that offer a global-scale delineation of industry-free land as wilderness with maps of carbon stock, species richness, and ground travel time from urban centers. Wilderness areas took variable forms in relation to carbon stock, species richness, and proximity to urban centers, where 10% of wilderness areas represented high carbon and species richness, 20% low carbon and species richness, and 3% high levels of remoteness (>48 h), carbon, and species richness. Approximately 35% of all remaining wilderness in 2013 was accessible in <24 h of travel time from urban centers. Although the construct of wilderness can be used to secure benefits in specific contexts, its application in conservation must account for contextual and social implications. The diverse characterization of wilderness under a global environmental conservation lens shows that a nuanced framing and application of the construct is needed to improve understanding, communication, and retention of its variable forms as industry-free places.

Formas de las Áreas Silvestres y sus Implicaciones para las Políticas y la Conservación Mundial Resumen Con la intención de asegurar paisajes terrestres y marinos libres de la industria, la protección de las áreas silvestres entró a la política internacional por primera vez como un objetivo formal en el primer borrador del Marco de Trabajo para la Biodiversidad Mundial Post-2020 bajo el Convenio sobre la Diversidad Biológica. Con este incremento en la presencia dentro de la política internacional, es oportuno considerar el grado al que el concepto de área silvestre ayuda a los objetivos de conservación mundial. Evaluamos este concepto mediante la superposición de mapas de la presión humana acumulada recientemente actualizados que brindan una definición a escala mundial de las tierras libres de industria con mapas del stock de carbono, riqueza de especies y el tiempo de traslado terrestre desde los centros urbanos. Las áreas silvestres mostraron formas variables con respecto al stock de carbono, la riqueza de especies y la cercanía a los centros urbanos, de las cuales el 10% representó una elevada riqueza de especies y presencia de carbono, el 20% una baja riqueza de especies y presencia de carbono y el 3% una elevada lejanía (>48 horas), presencia de carbono y riqueza de especies. Aproximadamente el 35% de todas las áreas silvestres en 2013 era accesible en <24 horas de traslado desde los centros urbanos. Aunque el concepto de áreas silvestres puede usarse para garantizar beneficios en contextos específicos, su aplicación en la conservación debe considerar las implicaciones contextuales y sociales. La caracterización diversa de las áreas silvestres bajo el lente de la conservación ambiental mundial muestra que un encuadre matizado y la aplicación de este concepto son necesarios para aumentar el conocimiento, la comunicación y la retención de sus formas variables como lugares libres de industria.