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Birds and their habitats are facing unprecedented threats from a multitude of threats. Threats to birds, and consequently their population trajectories, vary both across space and among species groups, and greater knowledge of these patterns will help inform bird conservation and management. Here, we adapt existing methods to estimate continental bird population loss to a regional scale. Our objectives were to (1) identify patterns in regional population change (abundance) for 141 species of landbirds breeding in the Southeast; (2) compare these with continental patterns for the same suites of species, and (3) examine whether population-level changes in the Southeast suggest immediate, regional conservation actions. We found that landbird population losses were overall similar in the Southeast and across North America (−21%). Shrikes, nightjars, and swifts experienced the largest proportional losses among families in both regions. Birds associated with early seral and emergent wetland habitats experienced the greatest losses as did partial migrants and species listed on the Birds of Conservation Concern list for southeastern Bird Conservation Regions. Facultative aerial insectivores experienced the greatest losses in both regions, while obligate aerial insectivores increased in the Southeast in contrast to continental declines, due to rapid population growth in Cliff Swallows (Petrochelidon pyrrhonota). Within the Southeast, the greatest bird losses were in Peninsular Florida and Gulf Coastal Prairie, while the Mississippi Alluvial Valley Bird Conservation Region – where extensive reforestation efforts have been undertaken – had the smallest losses. We found clear differences in patterns of landbird population loss between the Southeastern United States and North America, as well as within the Southeast region. Results from these analyses should provide conservation agencies and partnerships with additional information and new perspectives to guide landscape-level planning and on-the-ground bird conservation delivery efforts to help bring back the nearly three billion birds lost across North America since 1970.DisclaimerThe findings and conclusions in this article are those of the authors and do not necessarily represent the views of the U.S. Fish and Wildlife Service.

One of the most pressing questions in ecology and conservation centers on disentangling the relative impacts of concurrent global change drivers, climate and land-use/land-cover (LULC), on biodiversity. Yet studies that evaluate the effects of both drivers on species' winter distributions remain scarce, hampering our ability to develop full-annual-cycle conservation strategies. Additionally, understanding how groups of species differentially respond to climate versus LULC change is vital for efforts to enhance bird community resilience to future environmental change. We analyzed long-term changes in winter occurrence of 89 species across nine bird groups over a 90-year period within the eastern United States using Audubon Christmas Bird Count (CBC) data. We estimated variation in occurrence probability of each group as a function of spatial and temporal variation in winter climate (minimum temperature, cumulative precipitation) and LULC (proportion of group-specific and anthropogenic habitats within CBC circle). We reveal that spatial variation in bird occurrence probability was consistently explained by climate across all nine species groups. Conversely, LULC change explained more than twice the temporal variation (i.e., decadal changes) in bird occurrence probability than climate change on average across groups. This pattern was largely driven by habitat-constrained species (e.g., grassland birds, waterbirds), whereas decadal changes in occurrence probabilities of habitat-unconstrained species (e.g., forest passerines, mixed habitat birds) were equally explained by both climate and LULC changes over the last century. We conclude that climate has generally governed the winter occurrence of avifauna in space and time, while LULC change has played a pivotal role in driving distributional dynamics of species with limited and declining habitat availability. Effective land management will be critical for improving species' resilience to climate change, especially during a season of relative resource scarcity and critical energetic trade-offs.

Evaluation of protected area effectiveness is critical for conservation of biodiversity. Protected areas that prioritize biodiversity conservation are, optimally, located and managed in ways that support relatively large and stable or increasing wildlife populations. Yet evaluating conservation efficacy remains a challenging endeavor. We used an extensive community science data set, eBird, to evaluate the efficacy of protected areas for birds across the Gulf of Mexico and Atlantic coasts of the United States. We modeled trends (2007-2018) for 12 vulnerable waterbirds that use coastal areas during breeding or wintering. We compared two types of protected areas-sites where conservation organizations implemented active stewardship or management or both to reduce human disturbance (hereafter stewardship sites) and local, state, federal, and private protected areas managed to maintain natural land cover (hereafter protected areas)-as well as unprotected areas. We evaluated differences in trends between stewardship, protected, and unprotected areas across the Gulf and Atlantic coasts as a whole. Similar to a background sample, stewardship was known to occur at stewardship sites, but unknown at protected and unprotected areas. Four of 12 target species-Black Skimmer (Rynchops niger), Brown Pelican (Pelecanus occidentalis), Least Tern (Sternula antillarum), and Piping Plover (Charadrius melodus)-had more positive trends (two to 34 times greater) at stewardship sites than protected areas. Furthermore, five target species showed more positive trends at sites with stewardship programs than unprotected sites during at least one season, whereas seven species showed more positive trends at protected than unprotected areas. No species had more negative trends at stewardship sites than unprotected areas, and two species had more negative trends at protected than unprotected areas. Anthropogenic disturbance is a serious threat to coastal birds, and our findings demonstrate that stewardship to reduce its negative impacts helps ensure conservation of vulnerable waterbirds.La evaluación de la efectividad de las áreas protegidas es de suma importancia para la conservación de la biodiversidad. Las áreas protegidas que priorizan la conservación de la biodiversidad están, de manera óptima, ubicadas y manejadas de maneras que permiten el mantenimiento de poblaciones silvestres relativamente grandes y estables o en incremento. Aun así, la evaluación de la eficacia de la conservación todavía es un esfuerzo desafiante. Usamos un conjunto extensivo de datos de ciencia comunitaria, eBird, para evaluar la eficacia de las áreas protegidas a lo largo de las costas del Golfo de México y del Atlántico en los Estados Unidos. Modelamos las tendencias poblacionales (2007-2018) para doce aves acuáticas vulnerables que usan las áreas costeras durante la temporada de reproducción o de hibernación. Comparamos dos tipos de áreas protegidas - sitios en donde las organizaciones de conservación implementaron una gestión o manejo activo o ambos para reducir la perturbación humana (de ahora en adelante sitios de gestión) y las áreas protegidas locales, estatales, federales y privadas manejadas para mantener la cobertura natural del suelo (de ahora en adelante áreas protegidas) - así como las áreas desprotegidas. Evaluamos las diferencias en las tendencias entre las áreas de gestión, las protegidas y las desprotegidas a lo largo de las cosas del Golfo y del Atlántico como un todo. Similar a una muestra de fondo, se supo que la gestión ocurría en los sitios de gestión, pero no se sabía si ocurría en las áreas protegidas y desprotegidas. Cuatro de las doce especies analizadas - Rhynchops niger, Pelecanus occidentalis, Sternula antillarum y Charadrius melodus - tuvieron tendencias más positivas (2-34 veces mayor) en los sitios de gestión que en las áreas protegidas. Además, cinco especies mostraron más tendencias positivas en los sitios con programas de gestión que en los sitios desprotegidos al menos durante una temporada, mientras que siete especies mostraron más tendencias positivas en sitios protegidos que en las áreas desprotegidas. protegidas que en las desprotegidas. Ninguna especie tuvo más tendencias negativas en los sitios de gestión que en las áreas desprotegidas y dos especies tuvieron más tendencias negativas en las áreas protegidas que en las desprotegidas. La perturbación antropogénica es una amenaza seria para las aves costeras y nuestros hallazgos demuestran que la gestión para reducir sus impactos negativos ayuda a asegurar la conservación de aves acuáticas vulnerables.保护区有效性评估对生物多样性保护至关重要。优先保护生物多样性的保护区的选址和管理方式最好能够支持相对较大、保持稳定或不断增长的野生动物种群。然而, 保护效果的评估仍然是一项具有挑战性的工作。本研究使用社区科学数据集 eBird, 评估了横跨墨西哥湾和美国大西洋海岸的鸟类保护区的保护成效。我们估计了在沿海地区繁殖或越冬的 12 种易受危害的水鸟在 2007 - 2018 年的种群动态, 并比较了两种类型的保护区和未保护地区的情况, 其中保护区包括保护组织实施积极管理以减少人类干扰的地区)以下简称管理位点(, 以及由地方、州、联邦和私人设立的维持自然土地覆盖的保护区)以下简称保护区(。我们评估了整个墨西哥湾和大西洋沿岸得到管理、保护和未保护地区的鸟类种群动态差异。与背景样本类似, 管理位点得到了相应管理, 但保护区和不受保护的地区管理情况不明。我们关注的 12 个物种中有 4 个物种)黑剪嘴鸥 Rhynchops niger、褐鹈鹕 Pelecanus occidentalis 、小白额燕鸥 Sternula antillarum 和笛鸻 Charadrius melodus (在管理位点的种群比在保护区的种群增长更快)高 2 - 34 倍(。此外, 在至少一个季节内, 有 5 个目标物种在管理位点比在未保护地区表现出更积极的种群动态, 而7个目标物种在保护区比在未保护地区表现出更积极的种群动态。没有任何一个物种在管理位点比在未保护地区的种群有更明显的负面变化趋势, 而有 2 个物种在保护区比在未保护地区的种群有更负面的变化趋势。人为干扰会对沿海鸟类构成严重威胁, 而我们的研究结果表明, 通过管理工作减少人为干扰的负面影响有助于对易受干扰的水鸟进行保护。【翻译: 胡怡思; 审校: 聂永刚】.

Together climate and land-use change play a crucial role in determining species distribution and abundance, but measuring the simultaneous impacts of these processes on current and future population trajectories is challenging due to time lags, interactive effects and data limitations. Most approaches that relate multiple global change drivers to population changes have been based on occurrence or count data alone. We leveraged three long-term (1995-2019) datasets to develop a coupled integrated population model-Bayesian population viability analysis (IPM-BPVA) to project future survival and reproductive success for common loons Gavia immer in northern Wisconsin, USA, by explicitly linking vital rates to changes in climate and land use. The winter North Atlantic Oscillation (NAO), a broad-scale climate index, immediately preceding the breeding season and annual changes in developed land cover within breeding areas both had strongly negative influences on adult survival. Local summer rainfall was negatively related to fecundity, though this relationship was mediated by a lagged interaction with the winter NAO, suggesting a compensatory population-level response to climate variability. We compared population viability under 12 future scenarios of annual land-use change, precipitation and NAO conditions. Under all scenarios, the loon population was expected to decline, yet the steepest declines were projected under positive NAO trends, as anticipated with ongoing climate change. Thus, loons breeding in the northern United States are likely to remain affected by climatic processes occurring thousands of miles away in the North Atlantic during the non-breeding period of the annual cycle. Our results reveal that climate and land-use changes are differentially contributing to loon population declines along the southern edge of their breeding range and will continue to do so despite natural compensatory responses. We also demonstrate that concurrent analysis of multiple data types facilitates deeper understanding of the ecological implications of anthropogenic-induced change occurring at multiple spatial scales. Our modelling approach can be used to project demographic responses of populations to varying environmental conditions while accounting for multiple sources of uncertainty, an increasingly pressing need in the face of unprecedented global change.

Diurnally biased monitoring and research dominate our ecological understanding and guide conservation and management decisions regarding important indicator sea duck species, such as Surf Scoters (Melanitta perspicillata). Advances in telemetry technology are improving our ability to track wildlife across the entire 24-hr day. Using location data derived from birds with surgically implanted satellite transmitters and habitat layers within a GIS (geographic information system), we analyzed Surf Scoter location data to (1) estimate movement distances between diurnal and nocturnal sites, (2) assess differences in environmental conditions at diurnal and nocturnal use locations, (3) evaluate the environmental conditions influencing nocturnal habitat selection, and (4) develop a predictive model to estimate likely nocturnal resting areas across the Salish Sea, which is composed of the inland marine waters of British Columbia, Canada, and Washington State. Surf Scoters in the Salish Sea traveled an average of 4,287 m between diurnal and nocturnal habitats, but distances varied regionally. We found that distance to shore, water depth, tidal current, and vessel traffic influenced nocturnal habitat use. Surf Scoter nocturnal use sites were characterized by greater distances from shore and deeper water than diurnal locations, although scoters avoided areas with strong tidal currents and heavy shipping traffic at night. The Salish Sea is experiencing increased ship traffic from multiple U.S. and Canadian ports. Oil tanker and shipping container vessel traffic pose a potential threat to nocturnal scoter flocks aggregating in deeper water adjacent to and sometimes overlapping with shipping lanes in narrow, glacial-carved channels of the Salish Sea. Current oil spill response plans in Washington State waters utilize diurnal distribution data, lacking important nocturnal use data. Our findings provide critical nocturnal habitat use information that can improve oil spill response policy and highlight the importance of elucidating nocturnal ecology for marine vertebrate species.

The National Wildlife Refuge System (NWRS) provides one of the United States’ greatest protected area networks for wildlife conservation. As climate changes beyond historical ranges of variability, refuge managers are confronted with assessing the utility of refuges, including how to best manage refuges both individually and as a system to help species cope with rapid change. Using published species distribution models, we projected species-specific changes in environmental suitability for 590 native North American bird species under a 2°C future warming scenario (~2050s under RCP8.5) at 525 refuges. For each species, we classified projected changes in suitability (i.e., improving, stable, or worsening suitability) and whether they crossed a model-derived persistence threshold at a refuge (i.e., potential colonization or potential extirpation). Overall, we found that a quarter of species (23% in summer, 26% in winter) could be different (i.e., turnover) across the refuge system despite protections. Summer and winter communities are not equally affected, so managers should consider different strategies for the different seasons. We forecast a slight net species loss in summer, from a mean of 109.0 ± 0.8 to 102.0 ± 0.7 species per refuge. In winter, we forecast a net gain in species, from a mean of 97.1 ± 2.2 to 118.5 ± 1.8 species per refuge. This includes an average of 12 species per refuge that may overwinter rather than migrate south. Refuges at northern latitudes will see relatively more turnover in species, while southern and coastal refuges will see fewer changes. Despite these species changes, dominant habitat association groups (e.g., waterbirds, forest birds) will generally stay the same across most of the NWRS. Some species may be lost from the entire NWRS and can benefit in the near term from targeted management. Regions of high extirpation and colonization (i.e., at northern latitudes) can be prioritized for strategic additions of new refuges.

Occupancy modeling is used to evaluate avian distributions and habitat associations, yet it typically requires extensive survey effort because a minimum of 3 repeat samples are required for accurate parameter estimation. Autonomous recording units (ARUs) can reduce the need for surveyors on-site, yet their utility was limited by hardware costs and the time required to manually annotate recordings. Software that identifies bird vocalizations may reduce the expert time needed if classification is sufficiently accurate. We assessed the performance of BirdNET—an automated classifier capable of identifying vocalizations from >900 North American and European bird species—by comparing automated to manual annotations of recordings of 13 breeding bird species collected in northwestern California. We compared the parameter estimates of occupancy models evaluating habitat associations supplied with manually annotated data (9-min recording segments) to output from models supplied with BirdNET detections. We used 3 sets of BirdNET output to evaluate the duration of automatic annotation needed to approach manually annotated model parameter estimates: 9-min, 87-min, and 87-min of high-confidence detections. We incorporated 100 3-s manually validated BirdNET detections per species to estimate true and false positive rates within an occupancy model. BirdNET correctly identified 90% and 65% of the bird species a human detected when data were restricted to detections exceeding a low or high confidence score threshold, respectively. Occupancy estimates, including habitat associations, were similar regardless of method. Precision (proportion of true positives to all detections) was >0.70 for 9 of 13 species, and a low of 0.29. However, processing of longer recordings was needed to rival manually annotated data. We conclude that BirdNET is suitable for annotating multispecies recordings for occupancy modeling when extended recording durations are used. Together, ARUs and BirdNET may benefit monitoring and, ultimately, conservation of bird populations by greatly increasing monitoring opportunities.

For many avian species, spatial migration patterns remain largely undescribed, especially across hemispheric extents. Recent advancements in tracking technologies and high-resolution species distribution models (i.e., eBird Status and Trends products) provide new insights into migratory bird movements and offer a promising opportunity for integrating independent data sources to describe avian migration. Here, we present a three-stage modeling framework for estimating spatial patterns of avian migration. First, we integrate tracking and band re-encounter data to quantify migratory connectivity, defined as the relative proportions of individuals migrating between breeding and nonbreeding regions. Next, we use estimated connectivity proportions along with eBird occurrence probabilities to produce probabilistic least-cost path (LCP) indices. In a final step, we use generalized additive mixed models (GAMMs) both to evaluate the ability of LCP indices to accurately predict (i.e., as a covariate) observed locations derived from tracking and band re-encounter data sets versus pseudo-absence locations during migratory periods and to create a fully integrated (i.e., eBird occurrence, LCP, and tracking/band re-encounter data) spatial prediction index for mapping species-specific seasonal migrations. To illustrate this approach, we apply this framework to describe seasonal migrations of 12 bird species across the Western Hemisphere during pre- and postbreeding migratory periods (i.e., spring and fall, respectively). We found that including LCP indices with eBird occurrence in GAMMs generally improved the ability to accurately predict observed migratory locations compared to models with eBird occurrence alone. Using three performance metrics, the eBird + LCP model demonstrated equivalent or superior fit relative to the eBird-only model for 22 of 24 species-season GAMMs. In particular, the integrated index filled in spatial gaps for species with over-water movements and those that migrated over land where there were few eBird sightings and, thus, low predictive ability of eBird occurrence probabilities (e.g., Amazonian rainforest in South America). This methodology of combining individual-based seasonal movement data with temporally dynamic species distribution models provides a comprehensive approach to integrating multiple data types to describe broad-scale spatial patterns of animal movement. Further development and customization of this approach will continue to advance knowledge about the full annual cycle and conservation of migratory birds.

As climate change alters the global environment, it is critical to understand the relationship between shifting climate suitability and species distributions. Key questions include whether observed changes in population abundance are aligned with the velocity and direction of shifts predicted by climate suitability models and if the responses are consistent among species with similar ecological traits. We examined the direction and velocity of the observed abundance-based distribution centroids compared with the model-predicted bioclimatic distribution centroids of 250 bird species across the United States from 1969 to 2011. We hypothesized that there is a significant positive correlation in both direction and velocity between the observed and the modeled shifts. We then tested five additional hypotheses that predicted differential shifting velocity based on ecological adaptability and climate change exposure. Contrary to our hypotheses, we found large differences between the observed and modeled shifts among all studied bird species and within specific ecological guilds. However, temperate migrants and habitat generalist species tended to have higher velocity of observed shifts than other species. Neotropical migratory and wetland birds also had significantly different observed velocities than their counterparts, which may be due to their climate change exposure. The velocity based on modeled bioclimatic suitability did not exhibit significant differences among most guilds. Boreal forest birds were the only guild with significantly faster modeled-shifts than the other groups, suggesting an elevated conservation risk for high latitude and altitude species. The highly idiosyncratic species responses to climate and the mismatch between shifts in modeled and observed distribution centroids highlight the challenge of predicting species distribution change based solely on climate suitability and the importance of non-climatic factors traits in shaping species distributions.

The recognized gap between research and implementation in avian conservation can be overcome with translational ecology, an intentional approach in which science producers and users from multiple disciplines work collaboratively to co-develop and deliver ecological research that addresses management and conservation issues. Avian conservation naturally lends itself to translational ecology because birds are well studied, typically widespread, often exhibit migratory behaviors transcending geopolitical boundaries, and necessitate coordinated conservation efforts to accommodate resource and habitat needs across the full annual cycle. In this perspective, we highlight several case studies from bird conservation practitioners and the ornithological and conservation social sciences exemplifying the 6 core translational ecology principles introduced in previous studies: collaboration, engagement, commitment, communication, process, and decision-framing. We demonstrate that following translational approaches can lead to improved conservation decision-making and delivery of outcomes via co-development of research and products that are accessible to broader audiences and applicable to specific management decisions (e.g., policy briefs and decision-support tools). We also identify key challenges faced during scientific producer-user engagement, potential tactics for overcoming these challenges, and lessons learned for overcoming the research-implementation gap. Finally, we recommend strategies for building a stronger translational ecology culture to further improve the integration of these principles into avian conservation decisions. By embracing translational ecology, avian conservationists and ornithologists can be well positioned to ensure that future management decisions are scientifically informed and that scientific research is sufficiently relevant to managers. Ultimately, such teamwork can help close the research-implementation gap in the conservation sciences during a time when environmental issues are threatening avian communities and their habitats at exceptional rates and at broadening spatial scales worldwide. Turkey Nature Conservation; Christensen Fund; Conservation Leadership Programme; UNDP-GEF SGP; Whitley Fund; Puget Sound Partnership; Stillaguamish Tribe; Liber Ero Foundation; Cats and Birds National Advisory Committee; Stewardship Centre for British Columbia; Environment and Climate Change Canada; National Institute of Food and AgricultureUnited States Department of Agriculture (USDA)National Institute of Food and Agriculture; U.S. Department of AgricultureUnited States Department of Agriculture (USDA); Hatch Project funds; Mississippi Agricultural and Forestry Experiment Station; NOAANational Oceanic Atmospheric Admin (NOAA) - USA [NA16NOS4200088, 8200025414]; National Fish and Wildlife Foundation [324423]; Margaret A. Cargill Foundation; U.S. Department of Agriculture's Conservation Innovation Grants program; National Parks General Directorate Published version C.H.S. is grateful to KuzeyDoga's staff and volunteers, the people of Kars, and Turkey Nature Conservation and National Parks General Directorate for their support and also to the Christensen Fund, Conservation Leadership Programme, UNDP-GEF SGP, and the Whitley Fund for funding. The Puget Sound Ecosystem Monitoring Program avian monitoring project was made possible by funding from the Puget Sound Partnership and the Stillaguamish Tribe. A.A.D. acknowledges the Intermountain West Joint Venture and collaborating landowners and conservation professionals. A.M.V.F., E.A., and M.S.W. acknowledge the GoMAMN Steering Committee and Community of Practice. E.A.G. acknowledges the Liber Ero Foundation, The Cats and Birds National Advisory Committee, the Stewardship Centre for British Columbia, and Environment and Climate Change Canada for funding, support, and staff time. M.S.W. was supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, Hatch Project funds, the Mississippi Agricultural and Forestry Experiment Station, and NOAA Awards NA16NOS4200088 and 8200025414. The National Fish and Wildlife Foundation Grant 324423 supported A.M.V.F. and M.S.W. The Conservation Ranching program and Bird-friendliness Index development were made possible by funding from the Margaret A. Cargill Foundation and U.S. Department of Agriculture's Conservation Innovation Grants program and participation by dozens of ranchers. Public domain – authored by a U.S. government employee

Climate change poses an intensifying threat to many bird species and projections of future climate suitability provide insight into how species may shift their distributions in response. Climate suitability is characterized using ecological niche models (ENMs), which correlate species occurrence data with current environmental covariates and project future distributions using the modeled relationships together with climate predictions. Despite their widespread adoption, ENMs rely on several assumptions that are rarely validated in situ and can be highly sensitive to modeling decisions, precluding their reliability in conservation decision-making. Using data from a novel, large-scale community science program, we developed dynamic occupancy models to validate near-term climate suitability projections for bluebirds and nuthatches in summer and winter. We estimated occupancy, colonization, and extinction dynamics across species' ranges in the United States in relation to projected climate suitability in the 2020s, and used a Gibbs variable selection approach to quantify evidence of species-climate relationships. We also included a Bird Conservation Region strata-level random effect to examine among-strata variation in occupancy that may be attributable to land-use and ecoregional differences. Across species and seasons, we found strong evidence that initial occupancy and colonization were positively related to 2020 climate suitability, illustrating an independent validation of projections from ENMs across a large geographic area. Random strata effects revealed that occupancy probabilities were generally higher than average in core areas and lower than average in peripheral areas of species' ranges, and served as a first step in identifying spatial patterns of occupancy from these community science data. Our findings lend much-needed support to the use of ENM projections for addressing questions about potential climate-induced changes in species' occupancy dynamics. More broadly, our work highlights the value of community scientist observations for ground-truthing projections from statistical models and for refining our understanding of the processes shaping species' distributions under a changing climate.

The spatial habitat heterogeneity hypothesis posits that habitat complexity increases the abundance and diversity of species. In tropical forests, lianas add substantial habitat heterogeneity and complexity throughout the vertical forest profile, which may maintain animal abundance and diversity. The effects of lianas on tropical animal communities, however, remain poorly understood. We propose that lianas have a positive effect on animals by enhancing habitat complexity. Lianas may have a particularly strong influence on the forest bird community, providing nesting substrate, protection from predators, and nutrition (food). Understory insectivorous birds, which forage for insects that specialize on lianas, may particularly benefit. Alternatively, it is possible that lianas have a negative effect on forest birds by increasing predator abundances and providing arboreal predators with travel routes with easy access to bird nests. We tested the spatial habitat heterogeneity hypothesis on bird abundance and diversity by removing lianas, thus reducing forest complexity, using a large-scale experimental approach in a lowland tropical forest in the Republic of Panama. We found that removing lianas decreased total bird abundance by 78.4% and diversity by 77.4% after 8 months, and by 40.0% and 51.7%, respectively, after 20 months. Insectivorous bird abundance and diversity 8 months after liana removal were 91.8% and 89.5% lower, respectively, indicating that lianas positively influence insectivorous birds. The effects of liana removal persisted longer for insectivorous birds than other birds, with 77.3% lower abundance and 76.2% lower diversity after 20 months. Liana removal also altered bird community composition, creating two distinct communities in the control and removal plots, with disproportionate effects on insectivores. Our findings demonstrate that lianas have a strong positive influence on the bird community, particularly for insectivorous birds in the forest understory. Lianas may maintain bird abundance and diversity by increasing habitat complexity, habitat heterogeneity, and resource availability.

The Millennium Ecosystem Assessment described 4 classes of services or functions that ecosystems and their component parts deliver to the benefit of humans: provisioning, regulating, supporting, and cultural services. Birds, including Neotropical birds, provide a diverse array of services in all 4 classes. We review the literature describing ecosystem services provided by Neotropical birds, draw inference from studies of avian services in other regions when Neotropical studies are limited, and identify key information gaps. Neotropical birds provide provisioning services in the form of meat and eggs for food, and feathers for down and ornamentation. Regulating services are among the most valuable services provided by Neotropical birds, including pollination, pest control, seed dispersal, and scavenging. Neotropical birds also provide supporting services in the form of nutrient cycling, such as through the deposition of guano on offshore islands. Finally, Neotropical birds provide cultural services as pets (caged birds), sources of recreation (e.g., birdwatching, hunting), as well as by inspiring art, photography, and religious customs. Much remains to be learned about the ecology and natural history of many Neotropical birds before we can fully assign value—monetary, nonmaterial, or otherwise—to the services they provide. However, what we have learned to date makes it clear that humans benefit from birds through multiple services, including but not limited to pest reduction, pollination of some agricultural plants, and seed dispersal.

Count data suggest that Black Oystercatcher (Haematopus bachmani) has locally variable but globally stable populations. A simple, stage-based matrix population model for Black Oystercatcher was built and Monte Carlo simulations of the model were conducted using vital rates from peer-reviewed and gray literature. Simulations yielded a distribution of potential population growth rates that extended from 0.87 to 1.14 and was centered at 1.00, supporting the hypothesis of a globally stable Black Oystercatcher population. Sensitivity and elasticity analyses of the population model showed that potential population growth is particularly sensitive to changes in hatching success (i.e., proportion of eggs hatched), fledging success (i.e., proportion of chicks fledged), and breeding adult annual survival. These rates could be possible targets for population management should it become necessary given future changes in sea temperature, sea level, and coastal development. Pair productivity, which integrates hatching and fledging success, is suggested as a simple and valuable metric for monitoring population growth potential of Black Oystercatcher.

Delineating effects of climate change on biological communities is an urgent conservation challenge, as climate models predict increases in frequency and magnitude of climatic variability. Climate affects migratory animals at different times and locations throughout their annual cycles. Using long-term (50-year) population trajectories from the North American Breeding Bird Survey, we evaluated climate effects throughout the annual cycle for 37 species of aerial insectivorous birds, a group experiencing widespread population declines and exhibiting extensive within-species spatial synchrony but limited among-species concordance in population trajectories. We assessed the effects of five large-scale climatic indices at two temporal scales (current year and one-year lagged), two measures of seasonal winds, and four measures of seasonal storms (hereafter “winds and storms”) to test hypotheses about the magnitude of climatic effects that may explain trend variation in population trajectories. Climate covariates – notably the Atlantic Multidecadal Oscillation – improved the fit of 77% of regional population models relative to temporal variation alone. Climate indices, particularly when lagged, had stronger effects than migratory winds and storms on population trajectories. Climate effects were strongest on swallows, diurnal migrants, northerly-wintering species, and western breeding populations, and weakest on nightjars. Such strong yet idiosyncratic climate responses reveal the full annual cycle sensitivity of migratory aerial insectivores to climate change while reinforcing recent findings that the causes of aerial insectivorous bird population declines are complex and species-specific.

Understanding source dynamics of invasive species is crucial to their management. Free-ranging wild pigs (Susscrofa) have caused considerable ecological and agricultural damage throughout their global range, includingCanada. Objectives were to assess the spatial and temporal patterns in domestic wild boar and test the propagulepressure hypothesis to improve predictive ability of an existing habitat-based model of wild pigs. We reviewedspatiotemporal patterns in domestic wild boar production across ten Canadian provinces during 1991–2011 andevaluated the ability of wild boar farm distribution to improve predictive models of wild pig occurrence using aresource selection probability function for wild pigs in Saskatchewan. Domestic wild boar production in Canadaincreased from 1991 to 2001 followed by sharp declines in all provinces. The distribution of domestic wild boarfarms in 2006 improved the fit and predictive ability of the habitat-based model, and the number of boar farmsin adjacent rural municipalities had a relative variable importance of 0.84. Our results support the propagulepressure hypothesis, which states that establishment success is linked to source dynamics. Although eradicationof wild pigs is rarely feasible after establishment over large areas, effective management will depend onstrengthening regulations and enforcement of containment practices for Canadian domestic wild boar farms.Initiation of coordinated provincial and federal efforts to implement population control procedures forestablished wild pig populations are urgently needed to limit the spread of wild pigs and their impacts, andshould focus on areas with existing or historic domestic wild boar farms.

AimEvaluating conservation effectiveness is essential to protect at-risk species and to maximize the limited resources available to land managers. Over 60% of North American grassland and aridlands have been lost since the 1800s. Birds in these habitats are among the most imperiled in North America, yet most remaining habitats are unprotected. Despite the need to measure impact, conservation efforts on private and working lands are rarely evaluated, due in part to limited availability of suitable methods.LocationNorthern Great PlainsMethodsWe developed a novel metric to evaluate grassland and aridland bird community response to habitat management practices, the Bird-Friendliness Index (BFI), consisting of density estimates of grassland and aridland birds weighted by conservation need and a functional diversity metric to incorporate resiliency. We used the BFI to inform three assessments: 1) a spatial prioritization to identify ecologically significant areas for grassland and aridland birds, 2) estimation of temporal trends in grassland and aridland bird community resilience, and 3) evaluation of the effects of land management practices on grassland and aridland bird communities.ResultsThe most resilient bird communities were found in the Prairie Potholes region of Alberta, Saskatchewan, northern Montana, and North Dakota, and the lowest BFI values in the southern and western regions of the Northern Great Plains. BFI values varied little over time on average, but trends varied regionally, largely in response to interannual relative variability in grassland and aridland bird densities.Main conclusionsBFI values increased in response to simulated habitat management, suggesting that practices recommended for use in bird-friendly grassland habitat management plans will increase the abundance and resilience of the grassland and aridland bird community, and will be detected using the BFI. The BFI is a tool by which conservationists and managers can carry out accountable conservation now and into the future.

International audience; ubstantial effort has been dedicated to developing reliable monitoring schemes for North American bird populations,but our ability to monitor bird populations in the boreal forest remains limited because of the sparsity of long-term data sets, particularlyin northerly regions. Given the importance of the boreal forest for many migratory birds, we set out to (1) summarize the main challengesassociated with monitoring avian populations, (2) describe the available statistical tools for population monitoring and their applications,and (3) identify future directions to overcome current challenges in monitoring bird populations in the boreal forest. Defining anddelineating populations of interest and identifying the drivers that affect those populations present the greatest current challenges. Thisis because migratory birds may be affected by many population-limiting processes at different stages of their annual life cycles. Thesefactors are often hierarchically structured and can influence populations at the local, regional, or continental scales. Some of thechallenges associated with delineating populations and identifying population drivers can be addressed via the plethora of samplingand analytic methods available to examine population change over time. Choosing the proper analytic methods depends on the goalsof the study and the nature of the data such as single or multiple populations, repeated occurrence or count-based surveys, ordemographic rates. Recent advances in hierarchical and integrated population models make these analytic approaches some of themost promising avenues for the development of future methods. However, these tools require large data sets, and acquiring sufficientdata on bird populations and potential explanatory variables is difficult in the boreal forest. If the current challenges to monitoringbirds in the boreal forest are to be overcome, serious effort should be dedicated to integrating existing data and making them accessible.Enhancing survey effort through multispecies surveys will also play an important role. Implementing spatially balanced sampling planswith a rotating panel design could balance the trade-offs between spatial versus temporal replication at an affordable cost. Improvingthe accessibility of environmental covariates that are spatially and temporally explicit would also enable development of mechanisticpopulation models that improve our understanding of migratory bird population dynamics. Finally, given that long-term monitoringprograms can take many decades before delivering reliable population trends and that organizational priorities often change over time,we suggest that collaborative efforts will help ensure the long-term survival of new monitoring programs.

The increasing intensity of wetland stressors in the Upper Midwestern United States hastens the need to understand how matrix composition influences wetland bird occurrence and abundance. The optimal spatial scale for assessing species–habitat relationships is not always apparent, but may affect inference about wetland use and suitability. We developed occupancy and abundance models, accounting for imperfect detection, for 9 wetland bird species breeding in Minnesota. We evaluated land cover associations at 3 spatial scales (12.6 ha, 50.3 ha, and 4,000 ha), quantified species-specific sensitivity to wetland availability and matrix habitat composition (agricultural and developed land covers), and assessed ecoregional variation in occupancy and abundance. Amount of wetland cover was positively associated with occupancy of 89% of species and with abundance of 67% of species, but the spatial scale of support differed among species. American Bittern (Botaurus lentiginosus), Pied-billed Grebe (Podilymbus podiceps), and Wilson’s Snipe (Gallinago delicata) in particular were negatively impacted by anthropogenic land uses within the surrounding matrix, indicating a need to shift wetland conservation planning from the site scale to the landscape scale to capture pertinent drivers of wetland bird habitat use. Mean expected occupancy across all species was greatest in the Prairie Pothole Region (PPR), suggesting that restoration efforts within this ecoregion are likely to maintain wetland bird diversity. However, given the minimal total wetland availability and predominantly agricultural matrix in the PPR, protecting wetlands and upland buffers in the Aspen Parklands or Boreal ecoregions may represent a better investment for agricultural-sensitive species such as American Bittern, Sandhill Crane (Antigone canadensis), and Wilson’s Snipe. Our modeling approach provides a multi-species framework for identifying habitat management priorities; future applications at broader spatial extents can continue to improve wetland bird conservation in a region with high rates of wetland loss and degradation.

SummaryRecent studies have highlighted the threat that climate change poses to species, as areas of climatic suitability contract or shift across the landscape. North American Neotropical long-distant migrant bird species present a unique problem compared to sedentary species because climate change may differ significantly across their breeding and wintering grounds. Studying the potential future distributions of these birds is challenging on many levels, including the fact that our understanding of the wintering grounds of these species is quite poor. To address this issue, we analyse available eBird data during the winter season in the Western Hemisphere in an effort to further promote and direct citizen science efforts to focus on areas that are climatically undersampled. We used Mobility-Oriented Parity (MOP) to understand the areas where climates are most dissimilar from climates sampled by existing eBird checklists, creating a map that ranks the western hemisphere at a 10 km resolution for climatic sampling during the winter season. We found that parts of Mexico and Central America, areas of Colombia, almost the entire Amazon Basin, coastal Peru and Chile, and northern Argentina are climatically undersampled. As a test case, we then used the map of survey priorities to simulate additional sampling in Colombia and recalculated the rankings. Guiding additional sampling with the priorities reduced climate dissimilarities between sampled and unsampled grid cells more than when additional sampling expanded in proportion to current sampling efforts or based on geographic undersampling. Analyses of sampling coverage in environmental space, such as this, will be a useful tool for targeting monitoring effort for bird species.

The combined effects of global climate change and shifting patterns in land use have resulted in range shifts for many wildlife species, as favorable conditions have been created for species entering novel environments. Moose (Alces alces) are a forest specialist species but have recently expanded southward from their traditional range in the boreal and aspen parkland forests into the agriculture-dominated landscape of the Prairie Pothole Region in western Canada. We quantified habitat selection patterns for moose in an agriculture-dominated landscape in south-central Saskatchewan, Canada. We fitted 15 adult female moose with global positioning system collars and generated resource selection functions for summer (Jul–Sep) and winter (Dec–Feb). Our goal was to describe seasonal habitat selection patterns for moose using farmland. We buffered used and available locations by 100 m and quantified land cover types within buffers. To account for nonlinear habitat selection, we generated models with quadratic (squared) land cover terms. We found strong selection by moose for wetland and forest land cover types, a nonlinear selection of cereals with highest selection occurring at an intermediate percentage of cereals, and an avoidance of pulses (peas, beans, and lentils) in both seasons. Oilseeds were weakly selected in summer and weakly avoided in winter. Developed areas were avoided in both seasons. Our results suggest that moose select woody and tree-ringed wetlands for foraging and lay down in the wetlands or use the associated shade as thermoregulatory cover. The selection of these wetlands suggests a possible explanation for the successful expansion of moose into the Prairie Pothole Region. Consumption of crops by native ungulates is a cause for concern for local agricultural producers, with damage by moose increasing in south-central Saskatchewan. Our results have important management implications for managing human–wildlife conflict with wild ungulates in a novel ecosystem, with fenced exclosures around wetlands offering a potential solution to areas faced with extensive moose crop damage. The strong selection of wetland and forest land cover types emphasizes the importance of conservation efforts for the remaining wetlands and riparian buffers in the agriculture-dominated Prairie Pothole Region. © 2016 The Wildlife Society.

Human activity surrounding the Laurentian Great Lakes basin has significantly degraded coastal wetland habitats, resulting in severe marsh bird population declines and reduced coastal resilience to changing environmental conditions. Given the need to conserve remaining coastal wetlands for wildlife and people, we developed a spatial prioritization to identify the most important U.S. Great Lakes coastal wetlands for 14 marsh bird species. We modeled occurrence and relative abundance of each species using boosted regression trees, a machine learning algorithm, to relate standardized monitoring data to ten remotely-sensed environmental covariates. We then used Zonation conservation planning software to rank every wetland cell based on its importance for the suite of marsh bird species. Evaluation of the drivers of marsh bird occurrence and abundance revealed that open water, herbaceous wetland, latitude, longitude, and impervious surface were the most important predictors across focal species. The high-priority wetlands for marsh birds (defined as grid cells ranked in the top 20%) occurred along the shores of eastern Lake Ontario, western Lake Erie/St. Clair, Saginaw Bay, Green Bay, northern lakes Michigan and Huron, and western Lake Superior. Overall, less than half (42%) of high-priority coastal wetlands across the Great Lakes basin are currently under some level of protection, with Lake Ontario priority wetlands being the least protected (25%). Our findings represent an opportunity to improve coastal wetland conservation in a region where wetland loss and degradation continue to threaten marsh bird populations and the integrity of one of the world's largest freshwater ecosystems.

Several organizations run wildlife-gardening programs designed to mitigate the biodiversity loss and disconnect between humans and wildlife that commonly accompanies urbanization. The National Audubon Society runs the Plants for Birds and the Humminbirds at Home programs that, like others, recommend homeowners to establish diverse assemblages of native plants with supplemental feeders. Here, we use plant and hummingbird data from the Hummingbirds at Home program to determine whether common wildlife-gardening recommendations correlate with intended outcomes. Our results showed that, after statistically controlling for several variables related to observer effort and geography, the relative occurrence and relative frequency of hummingbird sightings during patch surveys was positively related to the (1) presence of hummingbird feeders in a patch, (2) number of nectar-provisioning flowering-plant taxa in a patch, (3) degree to which nectar-provisioning flowering-plants in a patch were endemic to the conterminous USA, and (4) lack of impervious surface (a common proxy for urban development) in the surrounding landscape. These results support previous studies that showed how recommendations from wildlife-gardening programs associate with intended outcomes, but do so across an exceptionally broad, national extent that varies enormously in physical and biological geography.

More people are engaging in recreation on public lands in the United States than ever before. However, increased recreation can be detrimental to wildlife species. Managers need to understand how recreational activities, such as driving motor vehicles through natural areas, can affect a range of species so that they can balance access to nature with preservation of wildlife communities. We assessed the effect of off-highway vehicle (OHV) use and OHV trail density on the abundance and diversity of bird species across Hollister Hills State Vehicle Recreation Area in California, USA. We collected data during three winter and two spring seasons spanning 2012 to 2014. We used a hierarchical community distance sampling model to compare bird community and species-level abundance for 30 species in spring and 18 species in winter and used raw counts of birds to compare Shannon diversity between OHV use and nonOHV use areas. Community-level bird abundance increased significantly with OHV trail density in both winter and spring and was significantly greater in OHV use areas than in nonOHV use areas during the winter, but not spring. Seven and eight species, in spring and winter respectively, were significantly more abundant with greater OHV trail cover, and none was significantly less abundant. OHV use had no significant effect on Shannon diversity. Thus, OHV recreation appears to have had nonnegative effects on abundance and no discernable effect on diversity of birds at Hollister Hills. Abundance is not always a good predictor of habitat quality, however, so further research is needed to understand the demographic consequences of OHV use on bird species.

Continent-wide bird counts by community volunteers provide valuable information about the conservation needs of many bird species. The statistical modeling techniques commonly used to analyze these counts provide robust long-term trend estimates from heterogeneous community science data at regional, national, and continental scales. Here we present a novel modeling framework that increases the spatial resolution of trend estimates, and reduces the computational burden of trend estimation, each by an order of magnitude. We demonstrate the approach with data for the American Robin (Turdus migratorius) from Audubon Christmas Bird Counts conducted between 1966 and 2017, and show that aggregate regional trend estimates from the proposed method align well with those from the current standard method. Thus, it appears that the proposed technique can provide reasonable large-scale trend estimates for users concerned with general patterns, while also providing higher resolution estimates for others examining correlates of abundance trends at finer spatial scales.

Tricolored blackbird (Agelaius tricolor) is a colonial breeder, largely restricted to grasslands, wetlands, and agricultural habitats of California. Tricolored blackbird abundance declined considerably during the 20th century. Recent trends have been less clear, however, hindering efforts to evaluate the conservation needs of the species. We assessed trends in tricolored blackbird colony size using the 2008, 2011, 2014, and 2017 Triennial Tricolored Blackbird Statewide Survey, a community-science effort involving hundreds of volunteer observers. After accounting for variation in observer characteristics and survey effort, we found a clear, statistically significant decline in colony size of approximately –5% per year, which translated to a decrease in colony size of approximately –40% between 2008 and 2017. To the extent that colony size is proportional to total abundance, this decline translates to a species half-life of roughly 15 years. We conclude that tricolored blackbird is in considerable need of protection and recovery efforts.

During the growing season, neonicotinoid insecticides are frequently transported to surface water systems after rainfall events. However, detectable levels of neonicotinoids have also been found in wetlands during early spring, after ice-off but before crop seeding, representing an unexpected long-term exposure risk for aquatic organisms. This suggests long-term persistence, though origins and transport mechanisms remain unknown. We sampled 16 agricultural fields in the Canadian Prairies to investigate whether snow meltwater, particulate matter, top- (15 cm) or bottom-layer (15 cm) snow were potential sources of spring neonicotinoid contamination to receiving wetlands. Agricultural fields were selected based on the previous year’s crop: eight canola fields (clothianidin-treated seed) and eight oat fields (un-treated). We further sampled the wetlands draining those same oat and canola fields from ice-off to seeding to assess changes in neonicotinoid concentrations over time. Top-layer snow was below the limit of quantification for both canola and oat fields. Neonicotinoid concentrations (sum of clothianidin and thiamethoxam) were highest in meltwater (canola, mean: 267 ± 72.2 ng L −1 ; max: 633), but also detected in bottom-layer snow (oat, mean: 36.1 ± 9.18 ng L −1 ; max: 92.9), and soil particulate matter (canola, mean: 10.2 ± 1.82 μg/kg; max: 17.2). Concentrations in meltwater showed a stronger relationship ( R 2 = 0.35) with initial concentrations in wetland water than any other source type. Temporary wetland hydrology is largely fed by meltwater thus spring total neonicotinoid concentrations were higher in temporary wetlands than seasonal/semi-permanent wetlands ( P = 0.003). Only clothianidin was detected in soil particulate matter samples, including from oat fields not treated the year before, confirming this compound can persist over multiple years under local field conditions. The results of this study suggest that under normal agricultural practices, wetlands in colder climates are likely to be contaminated even before seeding occurs through persistence of neonicotinoids in soil and transport by snowmelt and particulate to surface water during spring runoff.

Many animal species exhibit spatiotemporal synchrony in population fluctuations, which may provide crucial information about ecological processes driving population change. We examined spatial synchrony and concordance among population trajectories of five aerial insectivorous bird species: chimney swift Chaetura pelagica, purple martin Progne subis, barn swallow Hirundo rustica, tree swallow Tachycineta bicolor, and northern rough-winged swallow Stelgidopteryx serripennis. Aerial insectivores have undergone severe guild-wide declines that were considered more prevalent in northeastern North America. Here, we addressed four general questions including spatial synchrony within species, spatial concordance among species, frequency of declining trends among species, and geographic location of declining trends. We used dynamic factor analysis to identify large-scale common trends underlying stratum-specific annual indices for each species, representing population trajectories shared by spatially synchronous populations, from 46 yr of North American Breeding Bird Survey data. Indices were derived from Bayesian hierarchical models with continuous autoregressive spatial structures. Stratum-level spatial concordance among species was assessed using cross-correlation analysis. Probability of long-term declining trends was compared among species using Bayesian generalized linear models. Chimney swifts exhibited declining trends throughout North America, with less severe declines through the industrialized Mid-Atlantic and Great Lakes regions. Northern rough-winged swallows exhibited declining trends throughout the west. Spatial concordance among species was limited, the proportion of declining trends varied among species, and contrary to previous reports, declining trends were not more prevalent in the northeast. Purple martins, barn swallows, and tree swallows exhibited synchrony across smaller spatial scales. The extensive within-species synchrony and limited concordance suggest that population trajectories of these aerial insectivores are responding to large-scale but complex and species- and region-specific environmental conditions (e.g. climate, land use). A single driver of trends for aerial insectivores as a guild appears unlikely.

Tropical forest understory birds are declining globally for unknown reasons, indicating an urgent need to understand the causes. We review and synthesize studies investigating causes of these declines focusing on the Sarapiqui region of the Caribbean slope of Costa Rica. We discuss evidence for five potential causes of population declines motivated by current understanding of the effects of fragmentation, disturbance of remnant forests, climate change, and their possible interactions: (1) reduced forest area increases the probability of stochastic extirpation; (2) reduced connectivity among forest patches decreases population rescue opportunities; (3) degradation of preferred microhabitats due to, for example, abundant large mammals, jeopardizes specialized birds’ foraging opportunities; (4) high nest predation rates reduce productivity below replacement levels; and (5) changes in macro- and microclimate increase energetic demands and reduce survival. Our review documents how tropical forest loss and degradation likely impact understory birds through a variety of direct, indirect, and interrelated causes spanning multiple temporal and spatial scales and levels of biological organization. We propose that the processes affecting understory birds in the Sarapiqui region may be broadly representative of threats experienced by rainforest understory birds pantropically. Effective conservation will require consideration of such diverse and interacting factors.

Tropical rain forest understory insectivorous birds are declining, even in large forest reserves, yet the mechanisms remain unclear. Abundant large mammals can reshape forest structure, which degrades foraging microhabitat. We used six sites in Nicaragua, Costa Rica, and Panama with varying collared peccary (Pecari tajacu) density to test three linked hypotheses: (1) locally declining understory insectivores forage preferentially in liana tangles; (2) vine and liana density, cover, and frequency of dense tangles are lower in the presence of abundant collared peccaries; and consequently (3) abundant collared peccaries are associated with reduced understory insectivorous bird abundance. Three insectivores that declined at La Selva preferentially foraged in liana tangles: Checker-throated Antwren (Epinecrophylla fulviventris), Dot-winged Antwren (Microrhopias quixensis), and Ruddy-tailed Flycatcher (Terenotriccus erythrurus). Vine density, liana cover, liana tangle frequency, and forest cover were lower in the presence of collared peccaries relative to experimental mammal exclosures, with the greatest differences at La Selva Biological Station, Costa Rica. Across sites, five of seven vine and liana measures showed negative, curvilinear relationships with peccary densities. Vine and liana measures peaked at sites with intermediate peccary density, and were low at La Selva. Structural equation models suggest negative indirect effects of the collared peccaries on focal bird densities, mediated by vine and liana density, cover, or tangle frequency. Forest area and rainfall affected both lianas and birds, but collared peccaries also contributed to the reduced abundance of understory insectivores. Indirect effects such as that suggested here may occur even in large, protected forest reserves where large mammal communities are changing. Resumen A pesar de que las aves insectivoras de sotobosque de bosques lluviosos estan disminuyendo en los tropicos, e incluso en grandes reservas forestales, no se conocen los mecanismos causantes. Los grandes mamiferos en abundancia, pueden cambiar la estructura del bosque a traves de efectos troficos y no troficos, degradar microhabitats a traves del forrajeo. Utilizamos seis sitios en Nicaragua, Costa Rica y Panama con densidades diferentes de sainos (Pecari tajacu) para poner a prueba tres hipotesis con efecto en cadena: (1) varias aves insectivoras en disminucion forrajean preferiblemente en maranas de lianas, (2) la densidad de lianas y cobertura, y la frecuencia de maranas densas son mas bajos en la presencia de abundantes sainos, y en consecuencia (3) sainos abundantes se asocian con una reduccion de aves insectivoras de sotobosque. Tres aves insectivoras que disminuyeron en La Selva forrajearon preferiblemente en maranas de lianas: Epinecrophylla fulviventris, Microrhopias quixensis, y Terenotriccus erythrurus. La densidad de los bejucos, la cubierta de lianas, la frecuencia de maranas de lianas, y la cobertura de bosque fueron menores en presencia de sainos en relacion a exclusiones experimentales de mamiferos, con las mayores diferencias en Estacion Biologica La Selva, Costa Rica. En todos los sitios, cinco de las siete variables de bejucos y lianas mostraron relaciones negativas y curvilineas con densidades de sainos. Medidas de los bejucos y lianas fueron mayores en sitios con densidades intermedias de sainos, y estaban baja en La Selva. Los modelos de ecuaciones estructurales sugieren que los sainos tienen efectos indirectos negativos en la abundancia de aves focales, mediadas por la densidad y cubierta de bejucos y lianas o la frecuencia de maranas de lianas. El area del bosque y las lluvias tambien afectan a las lianas y a las aves, pero los sainos tambien contribuyeron a la disminucion de la abundancia de aves insectivoras de sotobosque. Los efectos indirectos documentados aqui pueden ocurrir incluso en grandes reservas forestales protegidas, donde las comunidades de mamiferos grandes estan cambiando.

Ecotoxicology research on polychlorinated biphenyl (PCB) mixtures has focused principally on short-term effects on reproduction, growth, and other physiological endpoints. Latent cognitive effects from early life exposure to low-level PCBs were examined in an avian model, the European starling (Sturnus vulgaris). Thirty-six birds, divided equally among 4 treatment groups (control = 0 µg, low = 0.35 µg, intermediate = 0.70 µg, and high = 1.05 µg Aroclor 1254/g body weight), were dosed 1 d through 18 d posthatch, then tested 8 mo to 9 mo later in captivity in an analog to an open radial arm maze. Birds were subject to 4 sequential experiments: habituation, learning, cue selection, and memory. One-half of the birds did not habituate to the test cage; however, this was not linked to a treatment group. Although 11 of the remaining 18 birds successfully learned, only 1 was from the high-dosed group. Control and low-dosed birds were among the only treatment groups to improve trial times throughout the learning experiment. High-dosed birds were slower and more error-prone than controls. Cue selection (spatial or color cues) and memory retention were not affected by prior PCB exposure. The results indicate that a reduction in spatial learning ability persists among birds exposed to Aroclor 1254 during development. This may have implications for migration ability, resource acquisition, and other behaviors relevant for fitness. Environ Toxicol Chem 2015;34:2513–2522. © 2015 SETAC

The Boreal Plains Ecozone (BPE) in Western Canada is expected to be an area of maximum ecological sensitivity in the 21st century. Successful climate adaptation and sustainable forest management require a better understanding of the interactions between hydrology, climate, and vegetation. This paper provides a perspective on the changing water cycle in the BPE from an interdisciplinary team of researchers, seeking to identify the critical knowledge gaps. Our review suggests the BPE will likely become drier and undergo more frequent disturbance and shifts in vegetation. The forest will contract to the north, though the southern boundary of the ecotone will remain in place. We expect detrimental impacts on carbon sequestration, water quality, wildlife, and water supplies. Ecosystem interactions are complex, and many processes are affected differently by warming and drying, thus the degree and direction of change is often uncertain. However, in the short term at least, human activities are the dominant source of change and are unpredictable but likely decisive. Current climate, hydrological, and ecological monitoring in the BPE are limited and inadequate to understand and predict the complex responses of the BPE to human activities and climate change. This paper provides a case study of how hydrological processes critically determine ecosystem functioning, and how our ability to predict system response is limited by our ability to predict changing hydrology. WIREs Water 2015, 2:505–521. doi: 10.1002/wat2.1098 For further resources related to this article, please visit the WIREs website.

Accurate and adaptive encoding of complex, dynamic visual information is critical for the survival of many animals. Studies across a range of taxa have investigated behavioral and neuronal responses to objects that represent a threat, such as a looming object approaching along a direct collision course. By investigating neural mechanisms of avoidance behaviors through recording multineuronal activity, it is possible to better understand how complex visual information is represented in circuits that ultimately drive behaviors. We used multichannel electrodes to record from the well‐studied locust nervous system to explore how object motion is reflected in activity of correlated neural activity. We presented locusts (Locusta migratoria) with objects that moved along one of 11 unique trajectories and recorded from descending interneurons within the ventral nerve cord. Spike sorting resulted in 405 discriminated units across 20 locusts and we found that 75% of the units responded to some form of object motion. Dimensionality reduction through principal component (PCA) and dynamic factor (DFA) analyses revealed population vector responses within individuals and common firing trends across the pool of discriminated units, respectively. Population vector composition (PCA) varied with the stimulus and common trends (DFA) showed unique tuning related to changes in the visual size and trajectory of the object through time. These findings demonstrate that this well‐described collision detection system is more complex than previously envisioned and will drive future experiments to explore fundamental principles of how visual information is processed through context‐dependent dynamic ensembles of neurons to initiate and control complex behavior.

Aim: Biologists increasingly recognize the roles of humans in ecosystems. Subsequently, many have argued that biodiversity conservation must be extended to environments that humans have shaped directly. Yet popular biogeographical frameworks such as biomes do not incorporate human land use, limiting their relevance to future conservation planning. 'Anthromes' map global ecological patterns created by sustained direct human interactions with ecosystems. In this paper, we set to understand how current conservation efforts are distributed across anthromes. Location: Global. Methods: We analysed the global distribution of IUCN protected areas and biodiversity hotspots by anthrome. We related this information to density of native plant species and density of previous ecological studies. Potential conservation opportunities in anthromes were then identified through global analysis and two case studies. Results: Protected areas and biodiversity hotspots are not distributed equally across anthromes. Less populated anthromes contain a greater proportion of protected areas. The fewest hotspots are found within densely settled anthromes and wildlands, which occur at the two extremes of human population density. Opportunities for representative protection, prioritization, study and inclusion of native species were not congruent. Main conclusions: Researchers and practitioners can use the anthromes framework to analyse the distribution of conservation practices at the global and regional scale. Like biomes, anthromes could also be used to set future conservation priorities. Conservation goals in areas directly shaped by humans need not be less ambitious than those in 'natural areas'.