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With rapid global change in the Anthropocene, it is important to understand and predict changes in species distributions that could potentially impact entire ecosystems. Turkey Vulture (Cathartes aura) distribution has been expanding and, as an obligate scavenger, its presence can have an impact on the ecosystems it inhabits. Here we investigated the relative impact of human population density and climate (temperature and precipitation) on Turkey Vulture presence. We used eBird community science data from 2010-2020 to create a species distribution model for Turkey Vultures across their entire range using a Random Forests algorithm. We then projected this distribution for the year 2070 to estimate any changes. Our model predicted an expansion in Turkey Vulture distribution during the breeding season of May-August. This suggests that areas of both North and South America where only seasonal, migratory Turkey Vultures currently exist can expect resident populations of Turkey Vultures in the future. Mild temperature was an important variable for presence during the nonbreeding season, whereas low human density was more important for predicting presence during the breeding season. The distribution of Turkey Vultures is widest during the breeding season, meaning that factors influencing the breeding range could be considered more important when considering range expansion. As such, our findings suggest that warmer boreal winters coupled with the potential presence of domestic carcasses in agricultural areas (i.e., low human density) are facilitating Turkey Vulture range expansion. This expansion has important implications for the scavenging community in northern latitudes where increased Turkey Vulture presence might impact other species relying on carrion. Key words: climate, global change, human density, random forests, range expansion, scavenger. Con el rápido cambio global en el Antropoceno, es importante entender y predecir cambios en distribución de especies que podrían potencialmente tener un impacto en ecosistemas completos. La distribución del zopilote de cabeza roja (Cathartes aura) se ha ido expandiendo y, como carroñero obligado, su presencia puede tener un impacto en los ecosistemas que habita. Aqui investigamos el impacto relativo de la densidad de población humana y del clima (temperatura y precipitación) en la presencia del zopilote de cabeza roja. Utilizamos datos de ciencia ciudadana de eBird del 2010-2020 para crear modelos de distribución de especies de los zopilotes de cabeza roja en su rango completo usando un algoritmo de Random Forests. Luego proyectamos su distribución para el año 2070 para estimar cambios posibles. Nuestro modelo predijo una expansión en la distribución del zopilote de cabeza roja durante la temporada reproductiva de mayo-agosto. Esto sugiere que áreas tanto de Norte como Sudamérica donde los zopilotes de cabeza roja eran solo estacionales migratorios podrían esperar tener poblaciones residentes de este zopilote en el futuro. La variable temperatura templada fue importante para la presencia durante la temporada no-reproductiva, mientras que la baja densidad humana fue un predictor más importante durante la temporada reproductiva. La distribución de los zopilotes de cabeza roja es más amplia durante la temporada reproductiva, lo que significa que los factores que influyen en el rango reproductivo podrían ser considerados más importantes al considerar la expansión de rango. Asi, nuestros hallazgos sugieren que inviernos boreales más cálidos junto con la presencia potencial de restos de animales domésticos en áreas agrícolas (es decir, de baja densidad humana) facilitan el rango de expansión del zopilote de cabeza roja. Esta expansión tiene implicaciones importantes para la comunidad de carroñeros en latitudes norteñas donde la presencia en aumento del zopilote de cabeza roja puede tener un impacto en otras especies dependientes de la carroña. Palabras clave: cambio global, carroñero, clima, densidad humana, expansión de rango., Vultures are declining on a global scale, with 62% of species showing declining populations and 57% threatened with extinction (IUCN 2020). In contrast to vulture populations in Africa and Asia, [...]

Supplemental feeding of wild ungulates has long been and remains a common practice across Europe and North America. Yet by drawing animals together, supplemental feeding can have unintended, negative effects on individual species and broader ecological processes. These include increased risk of disease transmission, intraspecific and interspecific competition, and predation, which are of management concern for white‐tailed deer (Odocoileus virginianus) in the southeastern United States given the arrival of nonnative wild pigs (Sus scrofa) and coyotes (Canis latrans). We conducted a field experiment between March and July of 2021 to assess the effects of supplemental feeding on spatiotemporal activity patterns of deer and wild pigs at wildlife feeders, and space use of coyotes in the Piedmont region of South Carolina, USA. We observed support for our hypothesis that interspecific competition through increased visitation by larger groups of competitor species reduces use of foraging sites by other subordinate ungulates, where feeders highly visited by wild pigs were rarely visited by deer. While adult deer and wild pigs generally did not shift their temporal activity patterns at feeders, juvenile temporal activity shifted to more frequent visits of feeders during the night, supporting our hypothesis that supplemental feed could increase risk to predator exposure, as coyotes tend to be active during crepuscular hours. Our findings suggest that supplemental feed put out to encourage deer activity could actually deter deer if wild pigs occupy that area, and has potential negative demographic effects if juveniles are at increased risk of predation. Collectively, based on our data, we do not recommend supplemental feeding in the southeastern United States where white‐tailed deer, coyotes, and wild pigs co‐occur. More broadly, given how widespread the legal use of supplemental feed remains across the United States, we encourage landowners and policymakers to consider the full suite of potential direct and indirect, short‐term and long‐term negative impacts supplemental feeding can have on both target and nontarget wildlife populations. [ABSTRACT FROM AUTHOR]

Highways can fragment habitat and be a significant mortality source for mammals. Wildlife exclusion fencing has been shown to reduce wildlife-vehicle collisions, but can also prevent animals from escaping the highway corridor if they enter at access roads or at fence ends. Earthen escape ramps, or “jumpouts,” have been proposed as a possible solution but remain relatively untested. From 2012-2014, we used wildlife cameras to continuously document wildlife use of four jumpout ramps constructed as part of a 2.5-mile wildlife exclusion fence project along Highway 101 near San Luis Obispo, California. Mule deer occasionally used the jumpouts, but quantifying the rate of utilization was confounded by repeated visits by the same individuals. Male and female deer appeared to have different responses to the jumpouts, which warrants deeper investigation using additional data collected from further monitoring through mid-2017. The longer dataset will also better document how individual deer learn to use the jumpouts. Fenced highways can also reduce connectivity unless there is sufficient use of crossing structures. We documented mountain lion, bobcat, black bear, and mule deer used culverts and underpasses in and adjacent to the wildlife fence zone from 2012-2014. Mule deer used the large underpasses almost exclusively, and rarely if ever used culverts. Bear used a wider variety of structures, and bobcats were detected at almost every site and at a higher rate than the other taxa. Mountain lion detections were quite rare, likely due to lower population density in the study area. We propose a deeper multivariate analysis of the factors influencing these species’ use of culverts including culvert dimensionality, nearby habitat, and proximity to cover, based on an expanded dataset of up to five years of continual monitoring at certain sites. The goal of these analyses is to provide information that will help reduce wildlife-vehicle collisions while facilitating regional wildlife connectivity.

Predators impose top‐down forces on prey populations, with the strength of those effects often varying over space and time and among demographic groups. In ungulates, predation risk is typically greatest for neonatal offspring, with some suggesting that predators can key in on adult activity to locate hidden neonates. However, few field studies to date have been able to directly assess the influence of maternal care on ungulate neonate survival. Using a population of white‐tailed deer under heavy coyote predation pressure, we tested the maternal dispersion hypothesis, which suggests the dispersion of maternal activity temporally and spatially attenuates risk of predation for ungulate neonates during this vulnerable altricial phase. We compared support for this hypothesis with more commonly tested hypotheses regarding the influence of habitat conditions and intrinsic factors on neonatal survival. Fawn survival to 16 weeks was 27.7%, with coyotes accounting for 59% of fawn mortalities. In support of our maternal temporal diffusion hypothesis, we found that neonatal survival decreased as more maternal visits (proportionally) occurred at night. The only other significant (p <.1) predictor of fawn survival was birth timing, with fawn survival decreasing as the season progressed. Given that fawn survival declined as the proportion of nighttime visits increased, and that wild pig presence and human disturbance can push doe and fawn activity toward nocturnal hours, additional research is needed to determine whether managing pig and human disturbance can decrease fawn mortality. More broadly, given the importance of recruitment in ungulate population dynamics, our finding opens a potentially important new line of inquiry on how maternal behaviors influence predation risk in large animal predator–prey ecology. [ABSTRACT FROM AUTHOR]

Resource pulses are ecologically important phenomenon that occur in most ecosystems globally. Following optimal foraging theory, many consumers switch to pulsatile foods when available, examples of which include fruit mast and vulnerable young prey. Yet how the availability of resource pulses shapes the ecology of predators is still an emerging area of research; and how much individual variation there is in response to pulses is not well understood. We hypothesized that resource pulses would lead to dietary convergence in our population, which we tested by tracking both population‐level and individual coyote diets for 3 years in South Carolina, USA. We (1) described seasonal dietary shifts in relation to resource pulses; (2) compared male and female diets across seasons; and (3) tested this dietary convergence hypothesis by quantifying individual dietary variation both across and within periods when resource pulses were available. We found that pulses of white‐tailed deer fawns and blackberries composed over half of coyote diet in summer, and persimmon fruits were an important component in fall. Male and female coyotes generally had similar diets, but males consumed more deer in fall, perhaps driven by scavenging more. We found support for our dietary convergence hypothesis, where individuals had more similar diets during resource pulses compared to a non‐pulse period. We also found that this convergence happened before peak availability, suggesting a non‐symmetric response to pulse availability. We show that nearly all coyotes eat fawns, suggesting that targeted efforts to remove "fawn killers" would be in vain. Instead, given how quickly coyotes collectively converge on resource pulses, our findings show that resource pulses could potentially be used by managers to alter the behavior of apex predators. More broadly, we open a new line of inquiry into how variation in individual foraging decisions scales up to shape the effects of resource pulses on ecological communities. [ABSTRACT FROM AUTHOR]

Site occupancy models (SOMs) are a common tool for studying the spatial ecology of wildlife. When observational data are collected using passive monitoring field methods, including camera traps or autonomous recorders, detections of animals may be temporally autocorrelated, leading to biased estimates and incorrectly quantified uncertainty. We presently lack clear guidance for understanding and mitigating the consequences of temporal autocorrelation when estimating occupancy models with camera trap data.We use simulations to explore when and how autocorrelation gives rise to biased or overconfident estimates of occupancy. We explore the impact of sampling design and biological conditions on model performance in the presence of autocorrelation, investigate the usefulness of several techniques for identifying and mitigating bias and compare performance of the SOM to a model that explicitly estimates autocorrelation. We also conduct a case study using detections of 22 North American mammals.We show that a join count goodness‐of‐fit test previously proposed for identifying clustered detections is effective for detecting autocorrelation across a range of conditions. We find that strong bias occurs in the estimated occupancy intercept when survey durations are short and detection rates are low. We provide a reference table for assessing the degree of bias to be expected under all conditions. We further find that discretizing data with larger windows decreases the magnitude of bias introduced by autocorrelation. In our case study, we find that detections of most species are autocorrelated and demonstrate how larger detection windows might mitigate the resulting bias.Our findings suggest that autocorrelation is likely widespread in camera trap data and that many previous studies of occupancy based on camera trap data may have systematically underestimated occupancy probabilities. Moving forward, we recommend that ecologists estimating occupancy from camera trap data use the join count goodness‐of‐fit test to determine whether autocorrelation is present in their data. If it is, SOMs should use large detection windows to mitigate bias and more accurately quantify uncertainty in occupancy model parameters. Ecologists should not use gaps between detection periods, which are ineffective at mitigating temporal structure in data and discard useful data. [ABSTRACT FROM AUTHOR]

Recruitment is central to diversity, equity, and inclusion (DEI) initiatives within higher education, but how faculty recruit their graduate students and consider DEI in this context remains unknown. We surveyed environmental science faculty across the United States, aiming to better understand what faculty value when recruiting, as well as when, how, and why they consider DEI. We show that faculty valued applicant character traits highest, followed by soft skills and relevant technical experience. DEI-related criteria were of low to medium importance and were generally rated lower by faculty who were White, male, and at R1 institutions, although there were nuances related to applicant degree (MS versus PhD), whether we were asking about the applicant's commitment to DEI or their demographic identity, and the stage of the recruitment process. We identified opportunities for more inclusive graduate recruitment, including higher pay, more objective evaluation strategies, and a need for institutions to incentivize productivity without undermining the faculty's ability to attract diverse graduate students. [ABSTRACT FROM AUTHOR]

Large carcasses often attract multiple carnivore species, so subordinate carnivores must weigh the reward of a profitable meal with the risk of being attacked by dominant carnivores. These risk–reward trade‐offs are likely influenced by a variety of factors, including scale‐dependent risk from dominant carnivores (e.g., short‐ vs. long‐term risk) and the amount of carcass remaining. In the southeastern United States, human hunters provision a large amount of white‐tailed deer carrion, which appears to be an important food source for coyotes (a novel top predator), but we know little about how coyotes influence the scavenging behavior of smaller carnivores. In this study, we evaluated the relative importance of risk from coyotes, vulture activity, forest structure, and remaining food on bobcat, gray fox, raccoon, and opossum scavenging by deploying 71 deer carcasses within a managed forest in South Carolina during January 2020 and 2021. We found that coyotes only had direct effects on bobcat behavior, suggesting that competition for carcasses was greatest between these two species. However, the relative importance of long‐ versus short‐term risk from coyotes was dependent on the stage in the scavenging process. Effects from forest structure were also stage‐dependent, where tree density and age were related to carcass discovery for bobcats and raccoons, while minimal understory cover facilitated bobcat, gray fox, and opossum scavenging, despite short‐term risk from coyotes. Vulture activity appeared to serve as a cue for gray foxes to discover carcasses. Ultimately, we found that risk from coyotes had species‐specific and context‐dependent effects on smaller carnivore scavenging. This represents some of the first direct evidence of how coyotes alter smaller carnivore behavior in a region where coyotes are a novel top predator. However, forest structure (particularly understory cover) seemed to mediate risk from coyotes, highlighting how habitat can influence predator–predator interactions. Future research should also investigate these interactions during other times of the year and try to quantify how human‐provisioned carcasses influence populations and communities. [ABSTRACT FROM AUTHOR]

Context: A central problem in road ecology is the need to minimise roadkill without exacerbating fragmentation. The best current solution to this problem is wildlife-exclusion fencing combined with crossing structures. However, because species vary in their propensity to use crossing structures, optimising their design for a suite of species remains a challenge. Aims: We investigated medium- and large-mammal use of undercrossings along Highway 101 in the Central Coast of California. Specifically, we quantified how undercrossing size, surrounding habitat, and the presence of a wildlife-exclusion fence, influenced overall species richness, as well as use by black bear, mule deer, puma, and bobcat. Methods: Using wildlife cameras, we documented mammal use at 11 undercrossings in our study area. We calculated the openness index of each undercrossing and remotely measured habitat features, such as percentage tree cover, and distance to nearest stream. We determined the relative importance of these factors on overall species richness, and the activity of focal species, using generalised linear mixed models in an information-theoretic framework. Key results: Mesocarnivores used a wider variety of undercrossings, and used them more frequently, than did larger mammals. Species richness and bear activity were greater closer to streams, and there was more bear activity at undercrossings within the wildlife-exclusion fence zone than outside it. Deer activity was strongly and positively related to undercrossing openness. Our puma and bobcat analyses were uninformative, likely because we detected puma too infrequently, and because bobcats showed little variation in use across sites. Conclusions: Our results support previous research highlighting natural travel corridors (e.g. riparian areas) as important places for wildlife crossings, both for a diversity of medium–large mammals and a low-density large carnivore. Ungulates may be the most selective taxa in respect to undercrossing use. Implications: Large, open undercrossings along natural travel routes accommodate the greatest diversity of medium–large mammal species. Designing wildlife crossing structures for a suite of species remains a challenge. We monitored 11 crossings along a major highway in California from 2012 to 2017 and found that mammal species richness and black bear use were greater closer to streams, whereas mule deer almost exclusively used large undercrossings. Large undercrossings associated with natural corridors are likely to promote connectivity for the most species of medium–large mammals. Photograph by the authors. [ABSTRACT FROM AUTHOR]

Wild pigs (Sus scrofa), which are invasive in many regions globally, can alter ecosystems and compete with native species through interference competition and resource exploitation. Wild pig impacts on other species may increase with greater niche overlap, which could vary over time based on environmental conditions, resource availability, or biological traits like diet, especially as seasonal variation in wild pig diet has been widely documented. A limited number of studies have assessed spatial or temporal overlap between native species and invasive wild pigs, with only a handful simultaneously assessing overlap in these niche dimensions. We investigated the potential for interspecific interactions involving invasive wild pigs in the Piedmont region of South Carolina, USA, by examining seasonal spatiotemporal overlap with other wildlife using N‐mixture models and diel activity overlap analyses. Site use by white‐tailed deer (Odocoileus virginianus) and coyote (Canis latrans) was negatively associated with wild pig activity in the fall, when the species had high diel activity overlap, indicating spatial partitioning could reduce interference competition with wild pigs in this season. Conversely, white‐tailed deer site use was positively associated with wild pig activity in the winter, suggesting higher spatial overlap may be necessary if resources are limited. Site use by bobcat (Lynx rufus) and nine‐banded armadillo (Dasypus novemcinctus) in the spring, along with raccoon (Procyon lotor) and wild turkey (Meleagris gallopavo) site use in the summer, was positively associated with wild pig activity. With the exception of diurnal wild turkey, diel activity overlap between these species and wild pigs was high, although temporal partitioning could have occurred at finer spatiotemporal scales than we examined. Our results collectively emphasize the importance of accounting for seasonal spatial and temporal responses by individual species to invasive wild pigs, with special consideration given to species in seasons where high niche overlap with wild pigs is anticipated. [ABSTRACT FROM AUTHOR]