Lotem Taylor

Human activities have profound impacts on ecological systems and biodiversity worldwide. Estimating wildlife response to those activities across broad spatial scales is challenging, yet effective conservation measures require an understanding of where and when these activities are contributing to population declines. We investigated the relationship between exposure to human activities (conservation challenges) and population trends of migratory warblers (Parulidae) that breed in the United States and Canada. Our four‐stage approach (1) summarizes the literature describing the sensitivity of species to conservation challenges; (2) estimates weekly species' exposure across the full annual cycle; (3) quantifies spatial correlations among species' exposure to conservation challenges; and (4) quantifies the relationships between seasonal exposure to conservation challenges and warbler population trends. Exposure during post‐breeding migration, followed by the stationary non‐breeding season and pre‐breeding migration, explained the most variation in warbler population trends. Within the post‐breeding migratory season, the conservation challenges with the greatest total seasonal exposure values were roads, light pollution, communication towers, forest management, and livestock management. During this season, species undergoing the steepest declines were associated with exposure to light pollution, communication towers, urban and suburban areas, livestock management, and agriculture. Notably, exposure to conservation challenges during the breeding season was not an important predictor of warbler population trends. Our results provide hemispheric, full annual cycle information for prioritizing conservation investments and additional research for warblers, specifically the importance of addressing challenges to which birds are exposed during post‐breeding migration. More broadly, this framework can be used to assess spatiotemporal conservation challenges impacting migratory species trends globally.

Global agreements to reduce the extinction risk of migratory species depend critically on intersecting migratory connectivity—the linking of individuals between regions in different seasons—and spatial patterns of environmental change. Here we integrate movement data from >329,000 migratory birds of 112 species to develop a parameter representing exposure to global change: multispecies migratory connectivity. We then combine exposure with projected climate and land-cover changes as a measure of hazard and species conservation assessment scores as a metric of vulnerability to estimate the relative risk of migratory bird population declines across the Western Hemisphere. Multispecies migratory connectivity (exposure) is the strongest driver of risk relative to hazard and vulnerability, indicating the importance of synthesizing connectivity across species to comprehensively assess risk. Connections between breeding regions in Canada and non-breeding regions in South America are at the greatest risk, which underscores the particular susceptibility of long-distance migrants. Over half (54%) of the connections categorized as very high risk include breeding regions in the eastern United States. This three-part framework serves as an ecological risk assessment designed specifically for migratory species, providing both decision support for global biodiversity conservation and opportunities for intergovernmental collaboration to sustain migratory bird populations year-round.

The conservation of migratory birds poses a fundamental challenge, their conservation requires coordinated action across the hemisphere, but those actions must be designed and implemented locally. To address this challenge, we describe a multilevel framework for linking broad‐scale, full annual cycle prioritizations to local conservation actions for migratory birds. We developed hemisphere‐scale spatial prioritizations for the full annual cycle of migratory birds that breed in six different ecosystems in North America. The full annual cycle prioritizations provide a hemispheric context within which regional priorities can be identified. Finer resolution, regional prioritizations can then inform local conservation actions more effectively. We describe the importance of local conservation practitioner contributions at each level of the process and provide two examples of regional spatial prioritizations that were developed to guide local action. The first example focused on coastal North and South Carolina, USA, and used information on marsh birds, shorebirds, ecological integrity, and co‐benefits for people to identify Cape Romain, South Carolina as a high‐priority site for conservation action. The second example in Colombia used information on migrant and resident birds to identify the Cauca Valley as a high‐priority site. The multilevel conceptual framework we describe is one pathway for identifying sites for implementation of local conservation actions that are guided by conservation priorities for migratory birds across their full annual cycle.

The conservation of migratory birds poses a fundamental challenge: their conservation requires coordinated action across the hemisphere, but those actions must be designed and implemented locally. To address this challenge, we describe a multi-level framework for linking broad-scale, full annual cycle prioritizations to local conservation actions for migratory birds. We developed hemisphere-scale spatial prioritizations for the full annual cycle of migratory birds that breed in six different ecosystems in North America. The full annual cycle prioritizations provide a hemispheric context within which regional priorities can be identifieed. Finer resolution, regional prioritizations can then inform local conservation actions more effectively. We describe the importance of local conservation practitioner contributions at each level of the process and provide two examples of regional spatial prioritizations that were developed to guide local action. The fierst example focused on coastal North and South Carolina, USA, and used information on marsh birds, shorebirds, ecological integrity, and co-benefiets for people to identify Cape Romain, South Carolina as a high-priority site for conservation action. The second example in Colombia used information on migrant and resident birds to identify the Cauca Valley as a high priority site. The multi-level conceptual framework we describe is one pathway for identifying sites for implementation of local conservation actions that are guided by conservation priorities for migratory birds across their full annual cycle.

Area-based conservation targets, such as ‘30−30’, if strategically applied, can increase resiliency to climate change and provide co-benefits to people and biodiversity. However, protected areas historically were not designated within the context of global change, and human communities at highest risk are often overlooked in conservation planning. To inform 30−30 conservation planning in the United States (i.e., America the Beautiful; ATB), we evaluated where US conservation opportunities exist by identifying habitats that can simultaneously benefit climate change mitigation and bird populations, as well as who lives in these areas and how conservation actions could both improve human well-being or potentially be at odds with local communities. To inform the equitable implementation of area-based conservation targets, we integrated maps of critical habitat for birds now and under a changing climate with carbon stocks and sinks and developed a prioritization framework to investigate the spatial alignment of these locations with areas identified as important for both human well-being and land-dependent human communities. Although nearly 30% of US lands have some level of protection, only 6% of US lands (143 million acres) are managed for biodiversity and align with Bird and Carbon (BC) priorities, and what counts as conservation actions towards the 30% goal and what successful conservation outcomes that benefit biodiversity, climate change mitigation, and human communities look like.

Climate‐informed spatial planning is urgently needed to guide initiatives aimed at both conserving biodiversity as a whole (e.g. protection of 30% of lands and waters by 2030) and recovering North American avifauna in particular. Various methods for prioritizing conservation areas exist, yet alternative methods may direct managers to different lands for protection, and thus varying recommendations for meeting area‐based targets. Here, we used bird species distribution models and landcover projections to systematically evaluate two widely used methods for prioritizing areas most likely to facilitate the persistence of multiple species under climate change: 1) in situ macrorefugia, identified as areas of high predicted species retention; and 2) complementarity‐based optimizations, identified using the Zonation conservation planning software. For 17 biogeographical groups in the continental United States, we compared priority areas for bird conservation derived from these two alternatives with respect to their spatial distributions and consensus (i.e. overlap), expected conservation outcomes (e.g. species and functional diversity), predicted climate change exposure, habitat characteristics, landscape configurations and degree of formal protection. Spatial distributions of priority areas differed by biogeographical group and method, with 40.5% consensus on average across groups. Consensus was extensive within mountainous and coastal regions, and limited at high latitudes (e.g. Alaska) and in flat, interior regions (e.g. grasslands). As expected, complementarity‐based optimizations more efficiently represented species than retention‐based in situ macrorefugia, especially for forest groups, and had greater overall biodiversity value and better habitat condition. Conversely, in situ macrorefugia encompassed higher elevations and larger contiguous patches and were expected to experience less winter‐season warming. Formal protection averaged < 50% across biogeographical groups, regardless of prioritization method. Our findings illustrate the value of complementarity‐based optimizations for bird conservation under climate change. More broadly, comparing approaches for prioritizing areas for long‐term species persistence can reveal critical trade‐offs in recommendations for climate‐informed protected area planning.

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.

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.

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.