Jerod A. Merkle

The recent surge in diverse, high‐resolution geospatial data—driven by advances in technologies such as GPS and remote sensing—has revolutionized the field of ecology, creating new opportunities for novel applications in wildlife management. However, the enormous volume and variety of available geospatial data, combined with the technical and logistical challenges of utilizing it, have made it difficult to leverage its full potential in wildlife management. Several platforms, such as Google Earth Engine (GEE) and Environmental‐Data Automated Track Annotation (Env‐DATA), have emerged to help address these barriers, but heavy coding requirements and limited support for customization have hindered applications at the regional scale. In this paper, we propose a scalable and accessible web Geographical Information Systems (GIS) system for archiving a curated geospatial library. The system is designed to support regional‐scale ecological research and management, and we illustrate with a case study focused on Wyoming and the Greater Yellowstone Ecosystem (GYE). Our system integrates cloud‐optimized geospatial formats, object‐oriented storage, and open‐source tools to provide streamlined access to a geospatial library. It eliminates the need for local data storage, promotes reproducibility, and enhances collaboration among researchers and practitioners. By focusing on regional applicability, our system addresses common challenges in geospatial data access and infrastructure, offering a replicable model for storing and delivering these data in an accessible way to the scientific and applied research communities.

Wildlife often lose access to habitat due to housing development. The magnitude of indirect habitat loss can be conditional on the configuration of individual houses, but commonly used metrics (i.e. density or distance) can overlook the configuration of development. We introduce a novel framework to index the configuration of development based on the width of space between houses and associated structures. We use resource selection functions to assess the degree that GPS‐collared elk ( Cervus canadensis ), mule deer ( Odocoileus hemionus ), pronghorn and moose ( Alces alces ) on winter range and on migration routes use space between houses within northwest Wyoming, USA, near the towns of Cody and Jackson. Further, to help inform regulations aiming to promote wildlife movement across a gradient of land uses, we differentiated between individuals residing in primarily rural and exurban areas. Rural populations of elk, mule deer, pronghorn and moose avoided spaces narrower than 2 km and never used spaces narrower than 50 m between houses, whereas exurban populations of elk, mule deer and moose selected for spaces narrower than 2 km but avoided spaces narrower than 50 m. We identified cutoffs in rural and exurban areas where space may become too narrow for most animals to use. Through this metric, managers and policy makers can inform the necessary width to maintain wildlife movement through corridors. Our width metric can be applied to other systems and our workflow is publicly available ( https://wildlifemovetools.org/width‐calculator ) so users can estimate the width of space between structures in their focal areas. Synthesis and applications . In rural areas, maintaining spaces between houses >500 m will likely facilitate ungulate movement. To fully conserve functional habitat, such as unimpeded habitat use along migration corridors, maintaining spaces approximately >2.5 km between houses will likely be necessary.

This report, volume 6 in the “Ungulate Migrations of the Western United States” report series, showcases the migrations of 23 ungulate herds in the Western United States. The report series is produced by the Corridor Mapping Team (CMT). Led by the U.S. Geological Survey, the CMT is a collaboration among 11 State agencies, as well as regional and Federal partners, and an expanding number of Tribal wildlife agencies. The CMT was initiated in response to the U.S. Department of the Interior Secretarial Order 3362, which was signed in 2018 and provided Federal support to expand existing research efforts to study ungulate populations and conserve their migrations throughout the Western United States. Including this volume, the report series has detailed the migrations of 237 unique ungulate herds throughout the Western United States and continues to serve as a valuable resource to guide local and regional management, policy, and on-the-ground work necessary to maintain intact and functional ungulate migrations. This report highlights several guiding principles of the CMT that facilitate collaboration among the diverse set of partners and contribute to the program’s continued successes. Notably, raw global positioning system data are not shared among participating agencies and the U.S. Geological Survey, delineating migration corridors and seasonal ranges relies on empirical data, the CMT provides flexible approaches to participating State and Tribal partners, and regular CMT meetings create a framework for open communication among agency partners that supports transboundary mapping of migrations. The 237 ungulate migrations that have been included in the report series are an expanding inventory, which can help maintain ungulate migrations in perpetuity.

Sudden habitat loss associated with environmental disturbance can trigger animals to move from affected to undisturbed areas, where increases in local density may occur. Although pathogen transmission is strongly related to local density, how crowding after habitat loss affects infection dynamics in wild populations remains unclear. Here we conceptualize the Disturbance‐Density‐Disease hypothesis, which posits that disturbance‐induced habitat loss results in increased pathogen prevalence via increases in local density at adjacent, undisturbed patches. We then used data from before, during, and after flooding disturbance to test this hypothesis in boreal toads Anaxyrus boreas boreas co‐occurring with the pathogenic fungus Batrachochytrium dendrobatidis ( Bd ). We collected Bd samples from captured individuals during a 5‐year (2015–2019) mark‐recapture study of boreal toads ( n = 1295) that breed in beaver ponds in western Wyoming, USA. During spring of 2017, an extreme flooding event destroyed several beaver dams, resulting in the loss of breeding habitat. We compared host density and pathogen prevalence pre‐ and post‐disturbance at sites affected versus unaffected by flooding. At affected sites, population density and Bd prevalence increased at adjacent, undisturbed ponds following the sudden loss of habitat. Moreover, neither host density nor Bd prevalence increased at control sites in areas unaffected by flooding. Taken together, our results support hypothesized links between disturbance, adjacent increases in density, and subsequent increases in pathogen prevalence. Our study contributes to a growing body of ecological research leveraging natural experiments to extract insights from extreme disturbance events. By doing so, we demonstrate an important consequence of disturbance beyond proximate habitat loss and introduce a clear conceptual approach (the Disturbance‐Density‐Disease hypothesis) to understanding how pathogen transmission can be affected by disturbance via alterations to local density.

Animal movement strategies are thought to be determined by the spatiotemporal variation of resources in an environment. Observations of various species indicate that the occurrence of migratory versus resident movements depends on resource predictability and the associated costs and benefits of tracking resource availability versus remaining in a familiar range. Here, we use 21 years of GPS data from seven populations ( n = 239) of pronghorn ( Antilocapra americana ) and 12 populations ( n = 283) of elk ( Cervus canadensis ) across Wyoming, USA to test if resource-based hypotheses predict individual movement strategies within a common geographic range. We identified three distinct movement strategies in each species—residents, dual-range migrants and multi-range migrants. Spatiotemporal variation in resources did explain variation in strategies in both pronghorn and elk, with residents experiencing less spatial and greater year-to-year variation than migratory individuals. However, spatiotemporal variation did not predict differentiation between dual- and multi-range migrants in either species. Climatic conditions were also important, especially in elk, where individuals were less likely to be resident when they experienced worse winters. Our findings demonstrate that the movement strategies of temperate ungulates are consistently linked to spatiotemporal resource variation across scales, but additional mechanisms can also facilitate localized behavioural differences.

Behavioral plasticity, the alteration of behavior in response to stimuli, is becoming increasingly important in the context of human‐induced rapid environmental change. Theoretical and empirical studies suggest that the expression and magnitude of behavioral plasticity are likely facilitated or constrained primarily by two factors: environmental variation and endogenous traits such as body size. The contextual role of these factors on behavioral plasticity, however, is poorly understood; there are relatively few studies that have compared the magnitude and potential drivers of behavioral plasticity at different levels (i.e., population and individual) across species, especially in free‐ranging animals with diverse behavioral traits such as large mammals. Here, we quantify and test potential hypotheses for the mechanisms underpinning behavioral plasticity at the individual and population level in response to variation in summer temperatures for 1068 animal‐years in 17 populations across nine species of large mammals. All populations displayed behavioral plasticity in response to increased temperatures, modifying their relative selection for heat‐relieving habitat attributes (e.g., elevation) and heat‐generating behavior (i.e., movement speed). We found strong support for the hypothesis that the variability of the physical environment is an important driver of behavioral plasticity—both mean population behavioral plasticity and variation among individuals within each population in plasticity were lower with increased heterogeneity of habitat attributes such as tree cover. Yet, the variability in environmental conditions (i.e., the magnitude of the temperature increase) had no effect on behavioral plasticity within and among populations. We did not detect an effect of endogenous traits on the expression of behavioral plasticity; however, we note that data availability limited our tests of this hypothesis to a select few endogenous traits (body size, feeding guild, and sex of the tracked individuals) that predominantly vary at the species level, for which we had one to three replicate populations per species. Our results provide an integrative and generalizable understanding of the expression of behavioral plasticity among populations of large mammals in temperate environments and emphasize the important but nuanced role of environmental variation in determining the scope of behavioral plasticity in these populations.

Understanding how animals learn in novel environments is crucial for predicting behavioral responses to rapid environmental change, yet we lack knowledge about how long different behaviors take to develop and refine, and how exploration facilitates learning. We tested the exploration–refinement hypothesis using movement and diet data from GPS‐collared bison Bison bison (n = 10) monitored for five years following reintroduction to Banff National Park. We examined how exploration influenced movement efficiency, habitat selection behaviors, and home range establishment. Different behaviors showed distinct learning trajectories. Movement efficiency in familiar areas reached an inflection point at 384 days, but when facing unfamiliar terrain, efficiency decreased as animals needed time to learn the new area. Habitat selection behaviors showed rapid initial improvement followed by extended refinement periods lasting up to three years. Exploratory movements occurred primarily in the first year (57%) but continued throughout the study and were positively correlated with improvements in habitat selection behaviors and home range stabilization, but not with movement efficiency. Our results demonstrate that exploration facilitates spatial learning – the process of acquiring and using information about environmental structure, distances, and relative positions to navigate effectively, locate resources, and avoid threats. This suggests that allowing individuals to explore while preventing large dispersal movements may be required for successful reintroductions. The extended timeline required for spatial behaviors to stabilize (3–4 years) indicates that behavioral refinement takes substantially longer than typically assumed, highlighting the need to align monitoring periods with the biological timeframes required for animals to learn novel environments.

For nearly half a century, ecologists have sought to explain animal space use through characteristics of the environment (i.e., habitat). Recent evidence suggests animals also use memory of previous experiences to decide when and where to move. Yet, the relative influence of the two in explaining animal space use has not been resolved. Using six large ungulate species in the Rocky Mountains (USA), we evaluated the performance of a habitat selection model with 16 environmental variables and another with two variables representing previous use (i.e., memory). While memory outperformed the environment for two species and the environment outperformed memory for four species, the influence of memory and the environment was overall comparable. The environment best explained the space use of specialists, while memory best explained species with strong site fidelity. Our work challenges traditional habitat selection theory, showcasing that animals build their spatial preferences through experience just as much as merely responding to their environment.

Although momentum is building to restore bison across North America, most efforts focus on small, managed herds, leaving unclear how large, migrating herds shape landscapes and whether their effects enhance or degrade ecosystems. We assessed carbon and nitrogen dynamics across the northern Yellowstone ecosystem, where one of the last remaining large migratory populations resides. Bison stabilized net aboveground production while accelerating nitrogen turnover, increasing aboveground nitrogen pools while carbon pools remained stable, which improved landscape nutritional quality. Effects were strongest in wet, nutrient-rich habitats that received higher bison densities and grazing than is recommended in rangeland management, while soil and plant conditions suggested landscape resilience. Restoration should embrace heterogeneity in densities and effects across habitats and spatial scales beyond those guiding most current recovery efforts.