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Halting the global decline of migratory birds requires a better understanding of migration ecology. Stopover sites are a crucial yet understudied aspect of bird conservation, mostly due to challenges associated with understanding broad-scale patterns of transient habitat use. Here, we use a national network of weather radar stations to identify stopover hotspots and assess multiscale habitat associations of migratory landbirds across the eastern United States during autumn migration. We mapped seasonal bird densities over 5 y (2015 to 2019) from 60 radar stations covering 63.2 million hectares. At a coarse scale, we found that landbirds migrate across a broad front with small differences in migrant density between radar domains. However, relatively more birds concentrate along the Mississippi River and Appalachian Mountains. At a finer scale, we identified radar pixels that consistently harbored high densities of migrants for all 5 y, which we classify as stopover hotspots. Hotspot probability increased with percent cover of all forest types and decreased with percent cover of pasture and cultivated crops. Moreover, we found strong concentrating effects of deciduous forest patches within deforested regions. We also found that the prairie biome in the Midwest (now mostly cropland) is likely a migration barrier, with large concentrations of migrants at the prairie–forest boundary after crossing the agricultural Midwest. Overall, the broad-front migration pattern highlights the importance of locally based conservation efforts to protect stopover habitats. Such efforts should target forests, especially deciduous forests in highly altered landscapes. These findings demonstrate the value of multiscale habitat assessments for the conservation of migratory landbirds.

We deposited the codes for running the microclimate model and endotherm model used in the study. We made customized versions of micro_terra (for using downloaded climate data) and endo_devel (for changing sequence of thermoregulation strategies and using Fortran for speed)from NicheMapR, which were also deposited.

India is the world’s largest consumer and importer of palm oil. In an aggressive push towards self-sufficiency in vegetable oils, the Indian government is prioritizing the rapid expansion of domestic oil palm plantations to meet an expected doubling in palm oil consumption in the next 15 years. Yet the current expansion of oil palm in India is occurring at the expense of biodiversity-rich landscapes. Using a spatially explicit model, we show that at the national scale India appears to have viable options to satisfy its projected national demand for palm oil without compromising either its biodiversity or its food security. At finer spatial scales, India’s oil palm expansion needs to incorporate region-specific contingencies and account for trade-offs between biodiversity conservation, climate change, agricultural inputs and economic and social security. The policy decisions that India takes with respect to oil palm can substantially reduce future pressures to convert forests to oil palm plantations in the tropics globally. The current expansion of oil palm in India is occurring at the expense of biodiversity-rich landscapes. This study shows that on the national scale India has the potential to become self-sufficient in palm oil production without compromising either its biodiversity or its food security, while economic, social, political and nutritional factors will require attention at finer spatial scales.

Wet markets have been implicated in multiple zoonotic outbreaks, including COVID-19. They are also a conduit for legal and illegal trade in wildlife, which threatens thousands of species. Yet wet markets supply food to millions of people around the world, and differ drastically in their physical composition, the goods they sell, and the subsequent risks they pose. As such, policy makers need to know how to target their actions to efficiently safeguard human health and biodiversity without depriving people of ready access to food. Here, we propose a taxonomy of wet markets, oriented around the presence of live or dead animals, and whether those animals are domesticated or wild (either captive-reared or wild-caught). We assess the dimensions and levels of risk that different types of wet markets pose to people and to biodiversity. We identify six key risk factors of wet markets that can affect human health: (1) presence of high disease-risk animal taxa, (2) presence of live animals, (3) hygiene conditions, (4) market size, (5) animal density and interspecies mixing, and (6) the length and breadth of animal supply chains. We also identify key factors informing risk to biodiversity. Finally, we recommend targeted, risk-adjusted policies to more efficiently and humanely address the dangers posed by wet markets.

Protected areas safeguard biodiversity, ensure ecosystem functioning, and deliver ecosystem services to communities. However, only ~16% of the world’s land area is under some form of protection, prompting international calls to protect at least 30% by 2030. We modeled the outcomes of achieving this 30 × 30 target for terrestrial biodiversity conservation, climate change mitigation, and nutrient regulation. We find that the additional ~2.8 million ha of habitat that would be protected would benefit 1134 ± 175 vertebrate species whose habitats currently lack any form of protection, as well as contribute to either avoided carbon emissions or carbon dioxide sequestration, equivalent to 10.9 ± 3.6 GtCO 2 year −1 (28.4 ± 9.4% of the global nature-based climate-change mitigation potential). Furthermore, expansion of the protected area network would increase its ability to regulate water quality and mitigate nutrient pollution by 142.5 ± 31.0 MtN year −1 (28.5 ± 6.2% of the global nutrient regulation potential).

Hundreds of millions of hectares of cropland have been abandoned globally since 1950 due to demographic, economic, and environmental changes. This abandonment has been seen as an important opportunity for carbon sequestration and habitat restoration; yet those benefits depend on the persistence of abandonment, which is poorly known. Here, we track abandonment and recultivation at 11 sites across four continents using annual land-cover maps for 1987–2017. We find that abandonment is largely fleeting, lasting on average only 14.22 years (SD = 1.44). At most sites, we project that >50% of abandoned croplands will be recultivated within 30 years, precluding the accumulation of substantial amounts of carbon and biodiversity. Recultivation resulted in 30.84% less abandonment and 35.39% less carbon accumulated by 2017 than expected without recultivation. Unless policymakers take steps to reduce recultivation or provide incentives for regeneration, abandonment will remain a missed opportunity to reduce biodiversity loss and climate change.

Is the Convention on International Trade in Endangered Species (CITES) up to the task of preventing species from being driven to extinction by trade? A new study documents some success but also highlights major deficiencies.

For the first time in history, more people live in urban areas than in rural areas. This trend is likely to continue, driven largely by rural-to-urban migration. We investigated how rural-to-urban migration, urbanization, and generational change affect the consumption of wild animals. We used chelonian (tortoises and freshwater turtles), one of the most hunted taxa in the Amazon, as a model. We surveyed 1356 households and 2776 school children across 10 urban areas of the Brazilian Amazon (6 small towns, 3 large towns, and Manaus, the largest city in the Amazon Basin) with a randomized response technique and anonymous questionnaires. Urban demand for wild meat (i.e., meat from wild animals) was alarmingly high. Approximately 1.7 million turtles and tortoises were consumed in urban areas of Amazonas during 2018. Consumption rates declined as size of the urban area increased and were greater for adults than children. Furthermore, the longer rural-to-urban migrants lived in urban areas, the lower their consumption rates. These results suggest that wild meat consumption is a rural-related tradition that decreases as urbanization increases and over time after people move to urban areas. However, it is unclear whether the observed decline will be fast enough to conserve hunted species, or whether children's consumption rate will remain the same as they become adults. Thus, conservation actions in urban areas are still needed. Current conservation efforts in the Amazon do not address urban demand for wildlife and may be insufficient to ensure the survival of traded species in the face of urbanization and human population growth. Our results suggest that conservation interventions must target the urban demand for wildlife, especially by focusing on young people and recent rural to urban migrants. Article impact statement: Amazon urbanite consumption of wildlife is high but decreases with urbanization, over time for rural to urban migrants, and between generations. Impactos de la Migración del Campo a la Ciudad, la Urbanización y del Cambio Generacional sobre el Consumo de Animales Silvestres en el Amazonas.Por primera vez en la historia, la población urbana es mayor que la rural. Es muy probable que esta tendencia continúe debido a la migración del campo a la ciudad. Investigamos el efecto de la migración del campo a la ciudad, la urbanización y el cambio generacional sobre el consumo de animales silvestres. Utilizamos como modelo a los quelonios (tortugas acuáticas y terrestres), uno de los taxa más cazados en el Amazonas. Aplicamos encuestas en 1,356 casas y a 2,776 niños en edad escolar en 10 áreas urbanas de la Amazonía brasileña (6 poblados pequeños, 3 poblados grandes y Manaos, la mayor ciudad en la Cuenca del Amazonas) mediante una técnica de respuesta aleatoria y cuestionarios anónimos. La demanda urbana de carne silvestre (i.e., carne de animales silvestres) fue alarmantemente alta. Aproximadamente 1.7 millones de tortugas acuáticas y terrestres fueron consumidas en áreas urbanas del Amazonas durante 2018. Las tasas de consumo declinaron a medida que incrementó la superficie urbana y fueron mayores en adultos que en niños. Más aun, entre más tiempo viviendo en áreas urbanas, las tasas de consumo fueron menores en los migrantes del campo a la ciudad. Estos resultados sugieren que el consumo de carne silvestre es una tradición rural que disminuye a medida que aumenta la urbanización y el tiempo desde que los habitantes se mueven a la ciudad. Sin embargo, no es claro si la declinación observada será lo suficientemente rápida para conservar a las especies cazadas, o si la tasa de consumo de los niños permanecerá igual cuando sean adultos. Por lo tanto, aun se requieren acciones de conservación en áreas urbanas. Los actuales esfuerzos de conservación en el Amazonas no abordan la demanda urbana de carne de monte y pueden ser insuficientes para asegurar la supervivencia de especies comercializadas ante la urbanización y el crecimiento de la población humana. Nuestros resultados sugieren que las intervenciones de conservación deben atender la demanda de fauna silvestre, con énfasis en los jóvenes y los migrantes recientes.

1. Identifying where and when population “bottlenecks” occur is critical to the conservation of migratory species, many of which are declining precipitously worldwide. Especially challenging is the evaluation of changes to staging sites. These sites are indispensable links in the migratory cycle but are typically used only briefly. 2. We devised a field-based approach to assess the quality and carrying capacity of a critical staging site in Nanpu, China, for the declining, migratory Red Knot (Calidris canutus rogersi & C. c. piersmai) during northward migration. The Nanpu tidal flat supports 50,000-100,000 Red Knotsannually, and while there, the knots feed almost exclusively on the bivalve Potamocorbula laevis. We simultaneously monitored changes in the abundance of Red Knots and bivalves across the entire staging site in spring 2018. 3. After taking into account potential competition with other shorebird species, we estimated that the Nanpu tidal flat was capable of supporting approximately 1.46-1.70 times the current observed level of usage of the site by Red Knots, and therefore is operating below, but close, to carrying capacity with respect to food resources for Red Knots. This result suggests that any further development of this site could harm the EAAF Red Knot population. 4. Synthesis and applications: Quantitative monitoring and evaluation of habitat quality of staging sites are essential to successfully conserve declining migratory species. In particular, researchers and conservation practitioners should incorporate both population size and staging duration in order to more accurately assess the importance of different sites and to quantify how changes in staging habitat quality may translate into changes in migrant population sizes at both local and global scales.

Several cryptic avian species have been validated by recent integrative taxonomic efforts in the Sino-Himalayan mountains, indicating that avian diversity in this global biodiversity hotspot may be underestimated. In the present study, we investigated species limits in the genus Tarsiger, the bush robins, a group of montane forest specialists with high species richness in the Sino-Himalayan region. Based on comprehensive sampling of all 11 subspecies of the six currently recognized species, we applied an integrative taxonomic approach by combining multilocus, acoustic, plumage and morphometric analyses. Our results reveal that the isolated north-central Chinese populations of Tarsiger cyanurus, described as the subspecies albocoeruleus but usually considered invalid, is distinctive in genetics and vocalisation, but only marginally differentiated in morphology. We also found the Taiwan endemic T. indicus formosanus to be distinctive in genetics, song and morphology from T. i. indicus and T. i. yunnanensis of the Sino-Himalayan mountains. Moreover, Bayesian species delimitation using BPP suggests that both albocoeruleus and formosanus merit full species status. We propose their treatment as 'Qilian Bluetail' T. albocoeruleus and 'Taiwan Bush Robin' T. formosanus, respectively.

For biodiversity protection to play a persuasive role in land-use planning, conservationists must be able to offer objective systems for ranking which natural areas to protect or convert. Representing biodiversity in spatially explicit indices is challenging because it entails numerous judgments regarding what variables to measure, how to measure them, and how to combine them. Surprisingly few studies have explored this variation. Here, we explore how this variation affects which areas are selected for agricultural conversion by a land-use prioritization model designed to reduce the biodiversity losses associated with agricultural expansion in Zambia. We first explore the similarity between model recommendations generated by three recently published composite indices and a commonly used rarity-weighted species richness metric. We then explore four underlying sources of ecological and methodological variation within these and other approaches, including different terrestrial vertebrate taxonomic groups, different species-richness metrics, different mathematical methods for combining layers, and different spatial resolutions of inputs. The results generated using different biodiversity approaches show very low spatial agreement regarding which areas to convert to agriculture. There is little overlap in areas identified for conversion using previously published indices (mean Jaccard similarity, Jw , between 0.3 and 3.7%), different taxonomic groups (5.0%

Smallholder agriculture is the main driver of deforestation in the western Amazon, where terrestrial biodiversity reaches its global maximum. Understanding the biodiversity value of the resulting mosaics of cultivated and secondary forest is therefore crucial for conservation planning. However, Amazonian communities are organized across multiple forest types that support distinct species assemblages, and little is known about smallholder impacts across the range of forest types that are essential for sustaining biodiversity. We addressed this issue with a large-scale field inventory of birds (point counts) and trees (transects) in primary forest and smallholder agriculture in northern Peru across 3 forest types that are key for Amazonian biodiversity. For birds smallholder agriculture supported species richness comparable to primary forest within each forest type, but biotic homogenization across forest types resulted in substantial losses of biodiversity overall. These overall losses are invisible to studies that focus solely on upland (terra firma) forest. For trees biodiversity losses in upland forests dominated the signal across all habitats combined and homogenization across habitats did not exacerbate biodiversity loss. Proximity to forest strongly predicted the persistence of forest-associated bird and tree species in the smallholder mosaic, and because intact forest is ubiquitous in our study area, our results probably represent a best-case scenario for biodiversity in Amazonian agriculture. Land-use planning inside and outside protected areas should recognize that tropical smallholder agriculture has pervasive biodiversity impacts that are not apparent in typical studies that cover a single forest type. The full range of forest types must be surveyed to accurately assess biodiversity losses, and primary forests must be protected to prevent landscape-scale biodiversity loss.Pérdida de Biodiversidad Pasada por Alto en la Agricultura de Pequeños Propietarios Resumen La agricultura de pequeños propietarios es la principal causa de la deforestación en la Amazonía occidental, donde la biodiversidad terrestre alcanza su máximo global. Por lo tanto, comprender el valor de la biodiversidad de los mosaicos resultantes de bosques cultivados y secundarios es crucial para para la planificación de la conservación. Sin embargo, las comunidades amazónicas están organizadas a través de múltiples tipos de bosques que soportan ensambles de especies distintas, y poco se sabe sobre los impactos de los pequeños agricultores en toda la gama de tipos de bosques que son esenciales para mantener la biodiversidad. Abordamos este problema con un inventario de campo a gran escala de aves (puntos de conteo) y árboles (transectos) en bosques primarios y agricultura de pequeños productores en el norte de Perú en 3 tipos de bosques que son clave para la biodiversidad amazónica. Para aves, la agricultura de pequeños productores soportó una riqueza de especies comparable a la de los bosques primarios dentro de cada tipo de bosque, pero la homogeneización biótica entre los tipos de bosques dio lugar a pérdidas sustanciales de biodiversidad en general. Estas pérdidas globales son invisibles para los estudios que se centran únicamente en los bosques de tierra firme. En el caso de árboles, las pérdidas de biodiversidad en bosques de tierra firme fueron dominantes en todos los hábitats combinados y la homogeneización en todos los hábitats no agravó la pérdida de biodiversidad. La proximidad a los bosques predijo robustamente la persistencia de especies de aves y árboles asociadas a bosques en el mosaico de pequeños productores, y debido a la omnipresencia de bosque intacto en el área de estudio, nuestros resultados probablemente representan el mejor escenario para la biodiversidad en la agricultura amazónica. La planificación del uso de suelo dentro y fuera de las áreas protegidas debe reconocer que la agricultura tiene impactos generalizados sobre la biodiversidad que no son evidentes en estudios que solo abarcan un solo tipo de bosque. Se debe examinar toda la gama de tipos de bosque para evaluar con precisión las pérdidas de biodiversidad, y los bosques primarios deben ser protegidos para prevenir la pérdida de biodiversidad a escala de paisaje.在全球陆地生物多样性最高的亚马逊西部地区, 小型农业生产是森林砍伐的主要驱动因素。因此, 了解小型农业中人工林和次生林镶嵌斑块的生物多样性价值, 对保护规划至关重要。然而, 亚马逊社区跨越了支持不同物种集合的多种森林类型, 而目前关于小型农业对维持生物多样性所必需的各种森林类型的影响研究甚少。为解决这个问题, 我们对秘鲁北部的原始林和小型农业用地中鸟类 (位点计数) 和树木 (样带) 进行了大规模的野外调查, 其中包含了对亚马逊生物多样性至关重要的三种类型的森林。对于鸟类来说, 小型农业用地维持的物种丰富度与各类型原始林相近, 但森林类型之间的生物同质化导致了总体生物多样性严重下降。然而, 只关注山地森林的研究发现不了这样的生物多样性总体丧失。对于树木来说, 山地森林的生物多样性丧失在所有生境中占主导地位, 而生境之间的生物同质化并不会加剧生物多样性丧失。与森林的距离显著地预测了小型农业镶嵌斑块中林鸟和树种的续存情况, 但由于本研究地点有广泛分布的原始林, 以上结果可能代表的是亚马逊农业生物多样性的最佳情况。进行保护地内外的土地利用规划时应认识到, 热带小型农业对生物多样性有普遍影响, 即使这一点在覆盖单一森林类型的典型研究中并不明显。因此, 未来的保护规划应全面调查各种类型的森林、准确评估生物多样性丧失, 并保护原始林以防止景观水平的生物多样性丧失。【翻译: 胡怡思; 审校: 聂永刚】.

To improve the likelihood of conservation success, donors, policy makers, nongovernmental organizations (NGOs), and researchers are increasingly interested in making conservation decisions based on scientific evidence. A major challenge in doing so has been the wide variability in the methodological rigor of existing studies. We present a simple framework to classify different types of conservation evidence, which can be used to understand the strengths, weaknesses, and biases in the conservation effectiveness literature. We then apply this framework to evaluate the evidence for the efficacy of four important strategies in tropical forest conservation. Even though there has been an increase in methodologically rigorous studies over time, countries that are globally important in terms of their biodiversity are still heavily under-represented by any type of conservation effectiveness evidence.

Globally, the overexploitation of wildlife presents one of the greatest challenges for biodiversity conservation and sustainable rural livelihoods. Research on the human dimensions of hunting is critical for identifying potential levers for behavioral change interventions. This is especially true in China where hunting threatens to extirpate avian species such as the green peafowl (Pavo muticus) and great hornbill (Buceros bicornis). Nevertheless, regulations restricting gun ownership and hunting have made interviews on this topic highly sensitive. Direct questions about conservation non-compliance are often affected by response bias such as refusals to answer or self-protective denials. We used the randomized response technique (RRT) to estimate the prevalence and drivers of illegal hunting targeting four focal bird taxa (barbets, bulbuls, partridges, and pheasants). Furthermore, we used statistical models that have recently been introduced to the conservation science literature to perform multivariate analyses for RRT data. We measured economic, demographic, and attitudinal covariates that could be associated with hunting. We found high awareness of laws banning hunting in Southwest China, but we also observed that 29.2% of the adult male population may have hunted birds in the past year. Contrary to previous findings highlighting subsistence and finance as major factors driving hunting, the most important predictors of hunting activity in this landscape were related to attitudes regarding the enjoyment of hunting. Extra-economic motivations, such as the entertainment value of hunting, may be underappreciated drivers of hunting behavior. Behavioral change interventions such as pride campaigns may be a promising approach to regulate bird hunting in Xishuangbanna in collaboration with local communities.

The illegal use of natural resources, manifested in activities like illegal logging, poaching, and illegal wildlife trade, poses a global threat to biodiversity. Addressing them will require an understanding of the magnitude of and factors influencing these activities. However, assessing such behaviors is challenging because of their illegal nature, making participants less willing to admit engaging in them. We compared how indirect (randomized response technique) and direct questioning techniques performed when assessing non-sensitive (fish consumption, used as negative control) and sensitive (illegal consumption of wild animals) behaviors across an urban gradient (small towns, large towns, and the large city of Manaus) in the Brazilian Amazon. We conducted 1,366 surveys of randomly selected households to assess the magnitude of consumption of meat from wild animals (i.e., wild meat) and its socioeconomic drivers, which included years the head of household lived in urban areas, age of the head of household, household size, presence of children, and poverty. The indirect method revealed higher rates of wildlife consumption in larger towns than did the direct method. Results for small towns were similar between the two methods. The indirect method also revealed socioeconomic factors influencing wild meat consumption that were not detected with direct methods. For instance, the indirect method showed that wild meat consumption increased with age of the head of household, and decreased with poverty and years the head of household lived in urban areas. Simultaneously, when responding to direct questioning, households with characteristics associated with higher wild meat consumption, as estimated from indirect questioning, tended to underreport consumption to a larger degree than households with lower wild meat consumption. Results for fish consumption, used as negative control, were similar for both methods. Our findings suggest that people edit their answers to varying degrees when responding to direct questioning, potentially biasing conclusions, and indirect methods can improve researchers' ability to identify patterns of illegal activities when the sensitivity of such activities varies across spatial (e.g., urban gradient) or social (e.g., as a function of age) contexts. This work is broadly applicable to other geographical regions and disciplines that deal with sensitive human behaviors.

Climate change and habitat degradation are amongst the two greatest threats to biodiversity. Together, they can interact to imperil species. However, how climate change and land-use change jointly affect the demographic vital rates that underpin population viability remains unknown. Here, using long-term data on birds from the increasingly degraded and rapidly warming Himalayas, we show that survival trends over time are linked to species' elevational ranges in primary, but not in selectively logged forest. In primary forest, populations at their cold-edge elevational range limit show increases in survival rates over time, whereas those at their warm-edge elevational range limit suffer survival declines. This pattern is consistent with species tracking favorable climatic conditions over time, leading to improved demographic outcomes at progressively higher elevations with climate change, which in turn lead to upslope range shifts. In logged forest, however, survival rates remain relatively constant over time. This suggests that, in response to climate change in the long term, individuals of the same species can maintain demographic vital rates in higher-elevation primary forest, but not in logged forest. This is the first demonstration of how two of the most disruptive anthropogenic influences on biodiversity interact to threaten survivorship in natural populations. Ignoring interactions between climate change and land-use change can potentially undermine accurate forecasting of the future of species in an increasingly warm and degraded world. Importantly, large tracts of well-protected primary forests across Earth's tropical elevational gradients may be essential to enable tropical montane species to persist in the face of climate change.

Key improvements are needed for implementation of the Endangered Species Act

As environmental scientists working in countries whose COVID-linked deaths already exceed their military casualties from all campaigns since 1945, we believe there are significant messages from the handling of this horrific disease for efforts addressing the enormous challenges posed by the ongoing extinction and climate emergencies.

Global biodiversity losses continue despite tremendous growth in the volume of conservation science and many local successes. Research that can achieve conservation science's aims—arresting declines in biodiversity and preventing extinctions—is therefore of ever greater importance. Here, we ask whether conservation science, as currently performed, is progressing in such a way as to maximize its impact. We present a simple framework for how effective conservation research could progress, from identifying problems to diagnosing their proximate and ultimate causes, and from proposing, to designing, implementing, and testing responses. We then demonstrate that for three well‐known examples—South Asian vultures, whooping cranes, and bycatch of procellariform seabirds—published studies appear to follow this sequence, with considerable benefits. However, for a representative sample of the wider conservation literature, we find no evidence of such a progression. Instead, the vast majority of papers remain focused on describing the state of nature or on mechanisms directly causing changes, with very little research on designing or implementing conservation responses. This lack of research on the sorts of questions that might most help conservation science deliver its stated mission strongly suggests we will struggle to translate the huge increase in research activity into real‐world benefits.

Migratory animals play vital ecological roles in ecosystems worldwide, yet many species are threatened by human activities. Understanding the detailed patterns of habitat use throughout the migration cycle is critical to developing effective conservation strategies for these species. Migratory shorebirds undertake some of the longest known migrations, but they are also declining precipitously worldwide. To better understand the dynamics of shorebird declines along the East Asian–Australasian Flyway, we quantified the spatiotemporal foraging distribution of 17 migratory shorebirds at two critical stopover sites. We found that shorebirds exhibit substantial interspecific and site-specific differences in their foraging distributions. Notwithstanding these differences, however, the upper tidal flats appear to be especially important to most shorebirds by providing more than 70% of the birds' cumulative foraging time, twofold greater than their proportional area. Because the upper tidal flats are also more prone to coastal development, our findings may help to explain why shorebird populations along the flyway have declined much faster than the overall rate of tidal flat loss. Our work highlights the importance of protecting upper tidal flats to conserve migratory shorebirds and demonstrates the value of a detailed ecological understanding of habitat usage by migratory animals for conservation planning.

The island of Borneo is a biodiversity hotspot of global importance that continues to suffer from one of the highest deforestation rates in the tropics. Selective logging concessions overlay a third of the remaining natural forests in the Indonesian part of Borneo, but many of these concessions have become inactive in recent years. Whereas the cessation of logging could be beneficial to biodiversity, the absence of a logging company's presence in the forest could also leave the concession open to deforestation by other actors. Using remote sensing analyses, we evaluate 1) whether inactive concessions are more likely to suffer from deforestation than active ones, 2) the possible reasons why concessions become inactive, and 3) which inactive concessions hold the most potential for biodiversity conservation, if protected from deforestation. Our analysis shows that, counterintuitively, inactive concessions overall suffer a higher rate of forest loss than active ones. We find that small concession size and high elevation are correlated with inactive status. We identified several inactive concessions that, if maintained as natural forest, could significantly contribute to biodiversity conservation, as exemplified by their importance to two umbrella species: Bornean orangutan (Critically Endangered) and Sunda clouded leopard (Vulnerable). Because timber operations in other tropical regions are likely to experience similar cycles of activity and inactivity, the fate of inactive timber concessions and the opportunities they create for conservation deserve much greater attention from conservation scientists and practitioners.

Aim: China's Grain for Green Program (GFGP) is the largest reforestation programme in the world and has been operating since 1999. The GFGP has promoted the establishment of tree plantations over the restoration of diverse native forests. In a previous study, we showed that native forests support a higher species richness and abundance of birds and bees than do GFGP plantations and that mixed-species GFGP plantations support a higher level of bird (but not bee) diversity than do any individual GFGP monocultures (although still below that of native forests). Here, we use metabarcoding of arthropod diversity to test the generality of these results. Location: Sichuan, China. Methods: We sampled arthropod communities using pan traps in the land cover types concerned under the GFGP. These land use types include croplands (the land cover being reforested under the GFGP), native forests (the reference ecosystem as the benchmark for the GFGP’s biodiversity effects) and the dominant GFGP reforestation outcomes: monoculture and mixed-species plantations. We used COI-amplicon sequencing (“metabarcoding”) of the arthropod samples to quantify and assess the arthropod community profiles associated with each land cover type. Results: Native forests support the highest overall levels of arthropod species diversity, followed by mixed-species plantations, followed by bamboo and other monocultures. Also, the arthropod community in native forests shares more species with mixed-species plantations than it does with any of the monocultures. Together, these results broadly corroborate our previous conclusions on birds and bees but show a higher arthropod biodiversity value of mixed-species plantations than previously indicated by bees alone. Main conclusion: In our previous study, we recommended that GFGP should prioritize the conservation and restoration of native forests. Also, where plantations are to be used, we recommended that the GFGP should promote mixed-species arrangements over monocultures. Both these recommendations should result in more effective protection of terrestrial biodiversity, which is an important objective of China's land-sustainability spending. The results of this study strengthen these recommendations because our policy prescriptions are now also based on a dataset that includes over 500 species-resolution taxa, ranging across the Arthropoda.

If current trends continue, the tropical forests of the Anthropocene will be much smaller, simpler, steeper and emptier than they are today. They will be more diminished in size and heavily fragmented (especially in lowland wet forests), have reduced structural and species complexity, be increasingly restricted to steeper, less accessible areas, and be missing many heavily hunted species. These changes, in turn, will greatly reduce the quality and quantity of ecosystem services that tropical forests can provide. Driving these changes will be continued clearance for farming and monoculture forest plantations, unsustainable selective logging, overhunting, and, increasingly, climate change. Concerted action by local and indigenous communities, environmental groups, governments, and corporations can reverse these trends and, if successful, provide future generations with a tropical forest estate that includes a network of primary forest reserves robustly defended from threats, recovering logged and secondary forests, and resilient community forests managed for the needs of local people. Realizing this better future for tropical forests and people will require formalisation of land tenure for local and indigenous communities, better-enforced environmental laws, the widescale roll-out of payments for ecosystem service schemes, and sustainable intensification of under-yielding farmland, as well as global-scale societal changes, including reduced consumerism, meat consumption, fossil fuel reliance, and population growth. But the time to act is now, while the opportunity remains to protect a semblance of intact, hyperdiverse tropical forests.

Lower-cost tropical forest restoration methods, particularly those framed as win–win business-protected area partnerships, could dramatically increase the scale of tropical forest restoration activities, thereby providing a variety of societal and ecosystem benefits, including slowing both global biodiversity loss and climate change. Here we describe the long-term regenerative effects of a direct application of agricultural waste on tropical dry forest. In 1998, as part of an innovative agricultural waste disposal service contract, an estimated 12,000 Mg of processed orange peels and pulp were applied to a 3 ha portion of a former cattle pasture with compacted, rocky, nutrient-poor soils characteristic of prolonged fire-based land management and overgrazing in Area de Conservacion Guanacaste, northwestern Costa Rica. After 16 years, the experimental plot showed a threefold increase in woody plant species richness, a tripling of tree species evenness (Shannon Index), and a 176% increase in aboveground woody biomass over an adjacent control plot. Hemispheric photography showed significant increases in canopy closure in the area where orange waste was applied relative to control. Orange waste deposition significantly elevated levels of soil macronutrients and important micronutrients in samples taken 2 and 16 years after initial orange waste application. Our results point to promising opportunities for valuable synergisms between agricultural waste disposal and tropical forest restoration and carbon sequestration.

The wildlife trade is now one of the greatest threats to biodiversity, and birds are among the most commonly traded groups worldwide. The demand for pet birds is especially high in Indonesia, a country with many exploited, imperiled bird species. Finding solutions to the threat that trade poses for birds, and wildlife in general, requires an understanding of its socioeconomic dimensions. We examined consumer demography and preferences of 762 bird owners in Medan, Sumatra, focusing on the differences among owners of birds taken from the wild versus birds bred in captivity. We found that the vast majority of bird owners have at least one wild-caught bird. However, wild-caught bird ownership is not uniformly distributed across Medan; rather, there are distinct hotspots with high proportions of people with wild-caught birds. The main reasons for owning wild-caught birds are lack of access to and the high cost of captive-bred birds, and a perception that captive-bred birds do not sing as well as wild-caught ones. We conclude that captive-breeding programs could reduce the pressure on wild populations, especially if suppliers are able to produce relatively cheap captive-bred birds. However, the perceived poorer song quality of captive-bred individuals might be a problem for the captive breeding of some species, notably the White-rumped Shama, Copsychus malabaricus. Since many owners of this species compete in bird song competitions, establishing competition categories specifically for captive-bred shamas could promote captive-bred bird ownership. Tackling the problem of the wild bird trade in Indonesia and elsewhere will require consideration of both the economic and the social factors that underlie pet ownership.

There is clear evidence that species' ranges along environmental gradients are constrained by both biotic and abiotic factors, yet their relative importance in structuring realized distributions remains uncertain. We surveyed breeding bird communities while collecting in situ temperature and vegetation data along five elevational transects in the Himalayas differing in temperature variability, habitat zonation, and bird richness in order to disentangle temperature, habitat, and congeneric competition as mechanisms structuring elevational ranges. Our results from species' abundance models representing these three mechanisms differed markedly from previous, foundational research in the tropics. Contrary to general expectations, we found little evidence for competition as a major determinant of range boundaries, with congeneric species limiting only 12% of ranges. Instead, temperature and habitat were found to structure the majority of species' distributions, limiting 48 and 40% of ranges, respectively. Our results suggest that different mechanisms may structure species ranges in the temperate Himalayas compared to tropical systems. Despite recent evidence suggesting temperate species have broader thermal tolerances than tropical species, our findings reinforce the notion that the abiotic environment has significant control over the distributions of temperate species.

The trade in wild animals involves one-third of the world's bird species and thousands of other vertebrate species. Although a few species are imperiled as a result of the wildlife trade, the lack of field studies makes it difficult to gauge how serious a threat it is to biodiversity. We used data on changes in bird abundances across space and time and information from trapper interviews to evaluate the effects of trapping wild birds for the pet trade in Sumatra, Indonesia. To analyze changes in bird abundance over time, we used data gathered over 14 years of repeated bird surveys in a 900-ha forest in southern Sumatra. In northern Sumatra, we surveyed birds along a gradient of trapping accessibility, from the edge of roads to 5 km into the forest interior. We interviewed 49 bird trappers in northern Sumatra to learn which species they targeted and how far they went into the forest to trap. We used prices from Sumatran bird markets as a proxy for demand and, therefore, trapping pressure. Market price was a significant predictor of species declines over time in southern Sumatra (e.g., given a market price increase of approximately $50, the log change in abundance per year decreased by 0.06 on average). This result indicates a link between the market-based pet trade and community-wide species declines. In northern Sumatra, price and change in abundance were not related to remoteness (distance from the nearest road). However, based on our field surveys, high-value species were rare or absent across this region. The median maximum distance trappers went into the forest each day was 5.0 km. This suggests that trapping has depleted bird populations across our remoteness gradient. We found that less than half of Sumatra's remaining forests are >5 km from a major road. Our results suggest that trapping for the pet trade threatens birds in Sumatra. Given the popularity of pet birds across Southeast Asia, additional studies are urgently needed to determine the extent and magnitude of the threat posed by the pet trade.

The demand for timber products is facilitating the degradation and opening up of large areas of intact habitats rich in biodiversity. Logging creates an extensive network of access roads within the forest, yet these are commonly ignored or excluded when assessing impacts of logging on forest biodiversity. Here we determine the impact of these roads on the overall condition of selectively logged forests in Borneo, Southeast Asia. Focusing on dung beetles along > 40 km logging roads we determine: (i) the magnitude and extent of edge effects alongside logging roads; (ii) whether vegetation characteristics can explain patterns in dung beetle communities, and; (iii) how the inclusion of road edge forest impacts dung beetle assemblages within the overall logged landscape. We found that while vegetation structure was significantly affected up to 34 m from the road edge, impacts on dung beetle communities penetrated much further and were discernible up to 170 m into the forest interior. We found larger species and particularly tunnelling species responded more than other functional groups which were also influenced by micro-habitat variation. We provide important new insights into the long-term ecological impacts of tropical logging. We also support calls for improved logging road design both during and after timber extraction to conserve more effectively biodiversity in production forests, for instance, by considering the minimum volume of timber, per unit length of logging road needed to justify road construction. In particular, we suggest that governments and certification bodies need to highlight more clearly the biodiversity and environmental impacts of logging roads., Highlights • Distinct edge effects along roads penetrate > 100 m into the logged forest interior. • Vegetation changes however, differed within a maximum of 34 m of the road edge. • Large diurnal, and tunnelling dung beetles are affected more by proximity to roads. • Micro-habitat variations shown to influence large tunnelling species.

AimChina’s Grain-for-Green Program (GFGP) is the largest reforestation program in the world and has been operating since 1999. The GFGP has promoted the establishment of tree plantations over the preservation of diverse native forest. In a previous study (Hua et al. 2016, Nat Comms 7:12717), we showed that native forest supports higher species richnesses of birds and bees than do GFGP plantations. We also showed that ‘mixed-plantation’ GFGP plantations, which are mostly made up of two to five neighboring monoculture stands of different tree species, planted in checkboard fashion, support a level of bird (but not bee) species richness that is higher than any of the individual GFGP monocultures, although still below that of native forest. To better protect terrestrial biodiversity, which is an important objective of China’s land-sustainability spending, we recommended that the GFGP should firstly prioritize native forest conservation and regeneration and secondly promote checkerboard planting arrangements over monocultures. Here, we use metabarcoding of arthropod biodiversity to test the generality of these results and policy recommendations.LocationSichuan, ChinaMethodsWe used COI-amplicon sequencing (‘metabarcoding’) of bulk samples of arthropods that were collected with pan traps in native forest, cropland, mixed plantations, and monocultures.ResultsNative forest supports the highest overall levels of arthropod species richness and diversity, followed by cropland and mixed plantations, followed by bamboo monoculture, followed by the other monocultures. Also, the arthropod community in mixed plantations shares more species with native forest than do any of the monocultures. Together, these results show a biodiversity value of mixed plantations for arthropods that is higher than that previously indicated by bees alone.Main conclusionThese results strengthen our original policy recommendations of (1) promoting the conservation and expansion of native forest and (2) promoting mixed-plantation arrangements. The value of this added metabarcoding-based analysis is that these policy prescriptions are now also based on a dataset that includes over 500 species-resolution taxa, ranging across the Arthropoda.

Reforestation is a critical means of addressing the environmental and social problems of deforestation. China's Grain-for-Green Program (GFGP) is the world's largest reforestation scheme. Here we provide the first nationwide assessment of the tree composition of GFGP forests and the first combined ecological and economic study aimed at understanding GFGP's biodiversity implications. Across China, GFGP forests are overwhelmingly monocultures or compositionally simple mixed forests. Focusing on birds and bees in Sichuan Province, we find that GFGP reforestation results in modest gains (via mixed forest) and losses (via monocultures) of bird diversity, along with major losses of bee diversity. Moreover, all current modes of GFGP reforestation fall short of restoring biodiversity to levels approximating native forests. However, even within existing modes of reforestation, GFGP can achieve greater biodiversity gains by promoting mixed forests over monocultures; doing so is unlikely to entail major opportunity costs or pose unforeseen economic risks to households., China's Grain for Green Program is the world's largest reforestation program, encompassing tens of millions of hectares since 1999. Here, Hua et al. show that the majority of areas have been reforested with tree monocultures, but that planting mixed forests could increase animal biodiversity without imposing additional economic costs.

Relative to long-distance migrants, altitudinal migrants have been understudied, perhaps because of a perception that their migrations are less complex and therefore easier to protect. Nonetheless, altitudinal migrants may be at risk as they are subject to ongoing anthropogenic pressure from land use and climate change. We used global positioning system/accelerometer telemetry to track the partial altitudinal migration of the satyr tragopan Tragopan satyra in central Bhutan. The birds displayed a surprising diversity of migratory strategies: some individuals did not migrate, others crossed multiple mountains to their winter ranges, others descended particular mountains, and others ascended higher up into the mountains in winter. In all cases migration between summer breeding and winter non-breeding grounds was accomplished largely by walking, not by flying. Females migrated in a south-easterly direction whereas males migrated in random directions. During winter, migrants occupied south-east facing slopes whereas residents remained on south-west facing slopes. Migratory and resident tragopans utilized a range of forest types, with migratory individuals preferring cool broadleaved forests during winter. These complex patterns of migration suggest that conservation measures should extend across multiple mountains, protect the full range of forest types and encompass multiple landscape configurations to protect aspect diversity. Given the diversity of migratory strategies employed by this single species it seems clear that more research on altitudinal migrants is needed to understand what must be done to ensure their future in an era of widespread land-use and climate change.