Shrub and grassland ecosystems are globally threatened, and loss and degradation continue to increase due to a variety of human activities. Many species of conservation concern live in these ecosystems and rely on small mammals, such as rabbits (Leporidae) and squirrels (Sciuridae) for prey. In North America, Wyoming contains one of the largest remaining intact shrubland ecosystems but is also the location of extensive energy development. We determined the response of small mammal abundance to surface disturbance (oil or gas well pads and roads), and to vegetation and topographic indices. We surveyed leporids and sciurids from 2012 to 2016 across Wyoming near occupied nests of ferruginous hawks (Buteo regalis), a raptor of conservation concern. We then predicted leporid and sciurid abundance given the existing amount of surface disturbance and for a scenario with no disturbance to quantify the landscape-scale effects of energy development on prey density. Finally, as a potential mechanism for differences in prey abundance, we tested for differences in remotely-sensed measures of vegetation between disturbed and undisturbed areas. We found that above-ground density of both leporids and sciurids was highest at undisturbed areas and lowest at roads. Current levels of disturbance result in 18% fewer leporids and 29% fewer sciurids compared to undisturbed sample sites. Vegetation cover differed significantly between undisturbed areas and disturbed, but not between disturbance types (roads and well pads). We conclude that energy infrastructure has an influence on fine-scale prey abundance but may be mediated by the maintenance of undisturbed areas in energy fields and revegetation of surface disturbance.
Increased fire frequency and severity in subalpine forests causes uncertainty regarding how forest-dependent species may respond to fire-disturbed landscapes relative to burn heterogeneity and severity. We tested individual-level habitat-use response of Canada lynx to fire severity, heterogeneity, patch characteristics, and unburned island refugia. We instrumented 22 Canada lynx (27 lynx years, 2018–2020) in the Northern Rocky Mountains, U.S.A. to investigate selection behavior in recent (≤ 3 yrs) fire-impacted landscapes using resource selection (RSF) and integrated step selection models (iSSF), functional response analyses, and hurdle models. Canada lynx increasingly avoided burned landscapes as disturbance became more prevalent within home ranges. At a finer scale (iSSF), lynx traversing burns selected high post-fire normalized burn ratio (NBR; i.e., low severity), high heterogeneity of severity, and near fire perimeters. Lynx exhibited strong selection for unburned islands, with 22.8
Human activities have significantly altered terrestrial ecosystems, leading to biodiversity loss and habitat fragmentation. Traditional methods for measuring human impacts often lack the precision required for localized assessments, fail to capture temporal dynamics or are scale‐limited. Human mobility data (HMD) from GPS‐enabled smartphone applications offers a valuable approach to understanding human movement patterns, overcoming many of these limitations. We present case studies demonstrating the use of HMD in assessing human activity within ecologically sensitive habitats (e.g. winter ranges and breeding grounds) and evaluating where human‐wildlife interactions are likely to occur to inform proactive conflict management. We also discuss how HMD can improve inference from habitat connectivity analyses and provide detailed, timely insights on how HMD can broadly support conservation and wildlife management goals. HMD revealed patterns of recreational use in bighorn sheep ( Ovis canadensis ) winter range and helped inform the timing and scope of protective measures for sheep. HMD also allowed us to quantify the frequency and timing of potential wildlife‐human interactions, such as cougar ( Puma concolor ) proximity to human activity, identifying high human‐wildlife conflict areas and opportunities to mitigate mortality risks (e.g. road crossings). We discussed how future uses of HMD can improve conservation and connectivity, allowing managers to assess barriers to movement, identify critical thresholds of human disturbance and refine strategies for mitigating impacts on species sensitive to human disturbance. We provided a simple example by highlighting differences in human use of a migration corridor for pronghorn ( Antilocapra americana ). Synthesis and applications . Human mobility data provides a transformative tool for wildlife management by offering scalable, dynamic insights into human activity that traditional methods cannot fully capture. These data enable managers to prioritize intervention areas, improve compliance with management zones, mitigate conflict risks, and enhance connectivity for sensitive species, supporting effective conservation strategies in a human‐dominated world.
To navigate, animals balance nearby perceptual cues, random search, and memory. Isolating the role of memory, however, remains difficult. Here, we use a mechanistic movement model to do so, simulating animals responding solely to local perceptual cues (i.e., lacking memory) and comparing their paths with actual routes taken. By comparing route efficiency, we evaluate whether actual routes incorporate knowledge beyond the perceptual range (i.e., spatial memory). We show that wolverines (Gulo gulo) employ spatial memory to plan routes through a rugged, mountainous landscape. Furthermore, we find that wolverines most commonly plan routes to destinations 5.3–9.8 km ahead. We estimate that route-planning saves wolverines, on average, 19.3 kcal per 135 min of movement. Our findings provide a template for evaluating how free-living animals recall the world beyond their perceptual range, offer a window into the cognitive mechanics underpinning navigation for this species, and support adding wolverines to the primate-dominated list of species with complex spatial memory.
Understanding how species distributions and associated habitat are impacted by natural and anthropogenic disturbance is central for the conservation of rare forest carnivores dependent on subalpine forests. Canada lynx at their range periphery occupy subalpine forests that are structured by large-scale fire and insect outbreaks that increase with climate change. In addition, the Southern Rocky Mountains of the western United States is a destination for winter recreationists worldwide with an associated high degree of urbanization and resort development. We modeled habitat for a reintroduced population of Canada lynx in the Southern Rocky Mountains using an ensemble species distribution model built on abiotic and biotic covariates and validated with independent lynx locations including satellite telemetry, aerial telemetry, camera traps, den locations, and winter backtracking. Based on this model, we delineated Likely and Core lynx-habitat as thresholds that captured 95
AbstractWolverine distribution contracted along the southern periphery of its range in North America during the 19th and 20th centuries due primarily to human influences. This history, along with low densities, sensitivity to climate change, and concerns about connectivity among fragmented habitats spurred the recent US federal listing of threatened status and special concern status in Canada. To help inform large scale landscape connectivity, we collected 882 genetic samples genotyped at 19 microsatellite loci. We employed multiple statistical models to assess the landscape factors (terrain complexity, human disturbance, forest configuration, and climate) associated with wolverine genetic connectivity across 2.2 million km2 of southwestern Canada and the northwestern contiguous United States. Genetic similarity (positive spatial autocorrelation) of wolverines was detected up to 555 km and a high-to-low gradient of genetic diversity occurred from north-to-south. Landscape genetics analyses confirmed that wolverine genetic connectivity has been negatively influenced by human disturbance at broad scales and positively influenced by forest cover and snow persistence at fine- and broad–scales, respectively. This information applied across large landscapes can be used to guide management actions with the goal of maintaining or restoring population connectivity.
Providing outdoor recreational opportunities to people and protecting wildlife are dual goals of many land managers. However, recreation is associated with negative effects on wildlife, ranging from increased stress hormones1,2 to shifts in habitat use3,4,5 to lowered reproductive success.6,7 Noise from recreational activities can be far reaching and have similar negative effects on wildlife, yet the impacts of these auditory encounters are less studied and are often unobservable. We designed a field-based experiment to both isolate and quantify the effects of recreation noise on several mammal species and test the effects of different recreation types and group sizes. Animals entering our sampling arrays triggered cameras to record video and broadcast recreation noise from speakers ∼20 m away. Our design allowed us to observe and classify behaviors of wildlife as they were exposed to acoustic stimuli. We found wildlife were 3.1-4.7 times more likely to flee and were vigilant for 2.2-3.0 times longer upon hearing recreation noise compared with controls (natural sounds and no noise). Wildlife abundance at our sampling arrays was 1.5 times lower the week following recreation noise deployments. Noise from larger groups of vocal hikers and mountain bikers caused the highest probability of fleeing (6-8 times more likely to flee). Elk were the most sensitive species to recreation noise, and large carnivores were the least sensitive. Our findings indicate that recreation noise alone caused anti-predator responses in wildlife, and as outdoor recreation continues to increase in popularity and geographic extent,8,9 noise from recreation may result in degraded or indirect wildlife habitat loss.
Divergent activity can change the intensity of species interactions, largely affecting species distributions and abundances, and consequently influencing the composition and function of ecological communities. Few assessments of activity patterns have focused questions around different resource constraints or have examined varying time frames when interaction strengths are expected to increase. We evaluated how activity among carnivores and their prey shifted from early to late winter, coinciding with a presumed decrease in food resources for carnivores, and we measured time between species detections within a camera station. Our study species were three forest carnivores—Pacific martens (Martes caurina), Rocky Mountain red foxes (Vulpes vulpes macroura), coyotes (Canis latrans); and two of their prey—American red squirrels (Tamiasciurus hudsonicus), and snowshoe hares (Lepus americanus). We sampled these species across an extensive network of cameras (n = 107) during the 2014–2017 winter seasons in the Greater Yellowstone Ecosystem, Wyoming. We generated kernel density plots for timing of photographs and calculated the coefficient of overlap among density plots for our predators and prey during early and late winter. Furthermore, we calculated the time-between-detections (i.e., hours) among forest carnivores. We found no consistent trends in time-between-detections across our species pairs. Pacific martens exhibited cathemeral activity that aligned with the peaks in activity of the two prey species. Temporal overlap between coyote and red fox activities was small in early winter, whereas coyotes modified activity in late winter such that they more closely aligned with red foxes. This intraguild convergence of activity may reflect an increase in resource constraints and have consequences for competitive interactions between these two canids. Our study supports the notion that variation in time is an important axis in facilitating coexistence among these forest carnivores and prey species.
Polyomaviruses are oncogenic viruses that are generally thought to have co-evolved with their hosts. While primate and rodent polyomaviruses are increasingly well-studied, less is known about polyomaviruses that infect other mammals. In an effort to gain insight into polyomaviruses associated with carnivores, we surveyed fecal samples collected in the USA from bobcats (Lynx rufus), pumas (Puma concolor), Canada lynxes (Lynx canadensis), and grizzly bears (Ursus arctos). Using a viral metagenomic approach, we identified six novel polyomavirus genomes. Surprisingly, four of the six genomes showed a phylogenetic relationship to polyomaviruses found in prey animals. These included a putative rabbit polyomavirus from a bobcat fecal sample and two possible deer-trophic polyomaviruses from Canada lynx feces. One polyomavirus found in a grizzly bear sample was found to be phylogenetically distant from previously identified polyomaviruses. Further analysis of the grizzly bear fecal sample showed that it contained anelloviruses that are known to infect pigs, suggesting that the bear might have preyed on a wild or domestic pig. Interestingly, a polyomavirus genome identified in a puma fecal sample was found to be closely related both to raccoon polyomavirus 1 and to Lyon-IARC polyomavirus, the latter of which was originally identified in human saliva and skin swab specimens but has since been found in samples from domestic cats (Felis catus).
Wildfires are increasing in scale and impact on the landscape, altering large amounts of wildlife habitat and forest ecosystems. The reduction of fuels through forest management is considered a primary way to reduce the extent and severity of wildfires before they occur but may lead to a decrease in tree density prohibitive of some species' habitat. Alternatively, management actions undertaken after a fire may speed the trajectory of burned areas back into quality habitat but may also impede this development if the wrong type of treatment is un-dertaken. Thus, information on how different management actions, applied either pre-or post-fire, can influence the timing of a burned area's return to suitable habitat will help managers conserve species on the landscape. Our study aims to understand how a rare carnivore, Canada lynx (Lynx canadensis), uses stands managed with different silviculture actions at different times relative to wildfire. We used GPS locations from 39 individual lynx collected from 2004 to 2015 to examine the response of lynx to wildfire compounded by active forest man-agement, where time since fire at time of use ranged from 1 to 27 years. To understand the drivers behind lynx use of wildfires, we also focused on the primary prey of Canada lynx, snowshoe hares (Lepus americanus), using pellet counts across a similar range of post-fire treatment types in fires between 22 and 28 years old. We also assessed vegetation recovery and forest structure over time since wildfire using remotely sensed data and field measurements. We found that lynx intensity of use differed based on timing and type of management action, with the greatest lynx use similar to 25 years after a wildfire managed with post-fire regeneration cuts (removal of the ma-jority of the canopy). Lynx use was likely driven by hare abundance, which was also highest in post-fire regeneration cuts, characterized at time of use by dense lodgepole pine stands. We conclude that managing landscapes with a mosaic of active (pre-and post-fire treatments) and passive (hands-off) management will best conserve a desirable range of lynx habitat in an increasingly fire-impacted landscape.
Central to species conservation in an era of increased disturbance from climate change is understanding the primary mechanisms that facilitate how forest-dependent species respond to changes in forest structure and composition. Here, we leveraged a natural experiment to investigate how changed forest structure and function pre-spruce-beetle ( Dendroctonus rufipennis ) and post-beetle disturbance influenced the regional distribution of Canada lynx ( Lynx canadensis ) at their southern range periphery. We compared the distribution of Canada lynx that were reintroduced into Colorado, USA from 1999–2006 to the current (2015–2017) distribution following a spatial large-scale spruce beetle outbreak from 2007 to 2016. Canada lynx did not substantially alter their distribution following the wide-spread alteration of forest structure and composition following the insect outbreak. We used the Bhattacharyya’s affinity metric to document that core (50% isopleth) and overall population ranges (95% isopleth) overlapped significantly at 50% and 77% respectively. In addition, areas of low and high relative use remained similar after the bark beetle outbreak and mapped onto one another in nearly a 1:1 fashion (Spearman rank correlation = 0.92, p < 0.01). The low impact of forest change on distribution was due to the keystone habitat elements (high horizontal forest cover, snowshoe hares) that remained functional. Thus, our results highlight that conservation scientists should increase their focus to understand the underlying mechanisms that impact wildlife distributions as climate-related disturbances becomes ever more amplified.
Animal conservation requires understanding animal-habitat relationships. The integration of novel remote sensing platforms such as Light Detection and Ranging (LiDAR) technology has dramatically improved the resolution of insight when evaluating animal-habitat relationships by characterizing forest structure. However, conventional LiDAR collection (e.g., airborne or terrestrial laser scanning) may be limited by small spatial extents and logistical constraints (e.g., budget) associated with sampling. NASA’s Global Ecosystem Dynamics Investigation (GEDI) mission provides an alternative and complement to conventional LiDAR sampling with globally available waveform LiDAR, which is being collected to characterize vertical and horizontal structure of Earth’s forests. Forest carnivores are wide-ranging species occupying forested ecosystems, and are generally associated with vertical and horizontal forest structure for their survival and reproduction. We evaluated patterns in occurrence and habitat use of forest carnivores, which included Pacific martens (Martes caurina), Rocky Mountain red foxes (Vulpes vulpes macroura), and coyotes (Canis latrans) and patterns in occurrence of their prey; American red squirrels (Tamiasciurus hudsonicus) and snowshoe hares (Lepus americanus). Camera trap data were collected during the 2014–2017 winters in the Greater Yellowstone Ecosystem in Wyoming, USA. Our objectives were to (1) combine GEDI samples with multispectral satellite imagery from Landsat 8 to upscale vertical forest structure metrics; (2) assess the relative importance of environmental characteristics influencing occurrence and habitat use of forest-associated predators and prey; and (3) determine if GEDI-derived variables aided our efforts in characterizing animal-environment relationships. We used Random Forest regression models to upscale GEDI samples across our study area and implemented a multi-tiered approach using generalized linear mixed effect models to simultaneously evaluate animal-environment relationships and how GEDI-derived metrics improved the animal-habitat models. GEDI-derived metrics of relative height and foliage height diversity improved our animal-environment models and were among the strongest covariates (effect sizes were 1.3–1.8 times larger than the next closest) in the coyote, red squirrel, and snowshoe hare models. All five species were influenced to some degree by the frequency of rebaiting a camera trap and varying conditions of snow depth. Collectively, our work indicates forest canopy height and complexity variables significantly improved our ability to assess the importance of forest characteristics on forest carnivores and their prey. Indeed, there is an untapped opportunity to enhance animal ecology and conservation planning with continued integration of GEDI information with freely available satellite data to characterize attributes of forest structure across expansive areas.
Abstract The application of species distribution models (SDMs) to areas outside of where a model was created allows informed decisions across large spatial scales, yet transferability remains a challenge in ecological modeling. We examined how regional variation in animal‐environment relationships influenced model transferability for Canada lynx (Lynx canadensis), with an additional conservation aim of modeling lynx habitat across the northwestern United States. Simultaneously, we explored the effect of sample size from GPS data on SDM model performance and transferability. We used data from three geographically distinct Canada lynx populations in Washington (n = 17 individuals), Montana (n = 66), and Wyoming (n = 10) from 1996 to 2015. We assessed regional variation in lynx‐environment relationships between these three populations using principal components analysis (PCA). We used ensemble modeling to develop SDMs for each population and all populations combined and assessed model prediction and transferability for each model scenario using withheld data and an extensive independent dataset (n = 650). Finally, we examined GPS data efficiency by testing models created with sample sizes of 5%–100% of the original datasets. PCA results indicated some differences in environmental characteristics between populations; models created from individual populations showed differential transferability based on the populations' similarity in PCA space. Despite population differences, a single model created from all populations performed as well, or better, than each individual population. Model performance was mostly insensitive to GPS sample size, with a plateau in predictive ability reached at ~30% of the total GPS dataset when initial sample size was large. Based on these results, we generated well‐validated spatial predictions of Canada lynx distribution across a large portion of the species' southern range, with precipitation and temperature the primary environmental predictors in the model. We also demonstrated substantial redundancy in our large GPS dataset, with predictive performance insensitive to sample sizes above 30% of the original.
Viruses in the families Circoviridae and Anelloviridae have circular single-stranded DNA genomes and have been identified in various animal species. Some members of the Circoviridae family such as beak and feather disease and porcine circovirus have been found to cause disease in their host animals. Anelloviruses on the other hand have not been identified to cause disease in their hosts but are highly prevalent in mammalian species. Using a non-invasive sampling approach, we identified novel circovirus and anelloviruses from faecal samples of wolverines dwelling in Montana, USA. Wolverines are forest carnivores that feed on a wide variety of carrion and other prey species, and they occupy diverse habitats across northern Europe to North America. Little is known about viruses associated with wild wolverines. Our investigation of the faecal samples resulted in the identification of a novel circovirus from three out of four wolverine samples, two collected in 2018 and one in 2019. Comparison with other circoviruses shows it is most closely related to a porcine circovirus 3, sharing ~69% identity. Additionally, three anellovirus genomes were recovered from two wolverine faecal samples which share 68‐–69% ORF1 nucleotide similarity with an anellovirus from another mustelid species, pine martens. Here we identify novel single-stranded DNA viruses associated with wolverine and open up new avenues for research.
Anellovirus infections are highly prevalent in mammals, however, prior to this study only a handful of anellovirus genomes had been identified in members of the Felidae family. Here we characterise anelloviruses in pumas (Puma concolor), bobcats (Lynx rufus), Canada lynx (Lynx canadensis), caracals (Caracal caracal) and domestic cats (Felis catus). The complete anellovirus genomes (n = 220) recovered from 149 individuals were diverse. ORF1 protein sequence similarity network analysis coupled with phylogenetic analysis, revealed two distinct clusters that are populated by felid-derived anellovirus sequences, a pattern mirroring that observed for the porcine anelloviruses. Of the two-felid dominant anellovirus groups, one includes sequences from bobcats, pumas, domestic cats and an ocelot, and the other includes sequences from caracals, Canada lynx, domestic cats and pumas. Coinfections of diverse anelloviruses appear to be common among the felids. Evidence of recombination, both within and between felid-specific anellovirus groups, supports a long coevolution history between host and virus.
Abstract There is an urgent need to understand ecological responses of avian species to the rapidly expanding human footprint of conventional and renewable energy development in sagebrush and prairie ecosystems. The ferruginous hawk (Buteo regalis) and golden eagle (Aquila chrysaetos) are two sympatric raptors of conservation concern that occupy and flourish in the most intact sagebrush steppe region remaining in North America. To understand these species’ use of habitat relative to energy development, we built resource selection functions using a spatially representative sample of occupied nesting territories collected in 2010–2011 and remotely sensed environmental variables across an extensive study area (186,693 km2). We used the resulting predicted resource selection maps to evaluate spatial overlap between the nesting habitats of these sympatric raptor species, as well as overlap of predicted habitat with potential development of oil/gas and wind energy resources. Remotely sensed variables were very effective in modeling patterns of nest‐site selection based on fivefold cross‐validation (>0.93 Spearman‐rank correlation) and validation with an independent dataset of historical nests collected from 2000 to 2009. Topographic roughness and intermediate levels of spring precipitation were the strongest drivers of differences in habitat use between ferruginous hawks and golden eagles. We did not detect a strong signal of avoidance of energy infrastructure by either species at current levels of development and both nested closer than expected to gravel/dirt roads associated with oil and gas infrastructure. However, extensive overlap of nesting habitat more selected by ferruginous hawks and golden eagles with areas of actual and potential energy development suggests both species are at risk from future habitat fragmentation. Given that 80% of nests are> 1 km from oil/gas wells, we believe the density of energy‐related disturbance present during our study was insufficient to drive patterns of resource selection for ferruginous hawks when considered at broad spatial scales. However, it was beyond the scope of our study to predict long‐term, population‐level responses. We suggest rigorous monitoring of long‐term trends in occupancy, productivity, and distribution is warranted for populations of ferruginous hawk and golden eagle in sagebrush and prairie ecosystems exposed to increased energy development.
The Northern Goshawk (hereafter referred to as Goshawk) is a large forest raptor, occupying boreal and temperate forests throughout the Holarctic. In North America, it breeds from Alaska to Newfoundland and south (Fig. 1). This partial migrant winters throughout its breeding range including occasionally the Great Plains and southeastern states; some individuals undergo short movements to lower elevations during winter, apparently in search of food. Irruptive movements of northern birds to the south occurs at approximately 10-year intervals that coincide with population lows of snowshoe hare (Lepus americanus) and grouse.