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Obtaining robust survival estimates is critical, but sample size limitations often result in imprecise estimates or the failure to obtain estimates for population subgroups. Concurrently, data are often recorded on incidental reencounters of marked individuals, but these incidental data are often unused in survival analyses.We evaluated the utility of supplementing a traditional survival dataset with incidental data on marked individuals that were collected ad hoc. We used a continuous time‐to‐event exponential survival model to leverage the matching information contained in both datasets and assessed differences in survival among adult and juvenile and resident and translocated Mojave desert tortoises (Gopherus agassizii).Incorporation of the incidental mark‐encounter data improved precision of all annual survival point estimates, with a 3.4%–37.5% reduction in the spread of the 95% Bayesian credible intervals. We were able to estimate annual survival for three subgroup combinations that were previously inestimable. Point estimates between the radiotelemetry and combined datasets were within |0.029| percentage points of each other, suggesting minimal to no bias induced by the incidental data.Annual survival rates were high (>0.89) for resident adult and juvenile tortoises in both study sites and for translocated adults in the southern site. Annual survival rates for translocated juveniles at both sites and translocated adults in the northern site were between 0.73 and 0.76. At both sites, translocated adults and juveniles had significantly lower survival than resident adults. High mortality in the northern site was driven primarily by a single pulse in mortalities.Using exponential survival models to leverage matching information across traditional survival studies and incidental data on marked individuals may serve as a useful tool to improve the precision and estimability of survival rates. This can improve the efficacy of understanding basic population ecology and population monitoring for imperiled species., Survival estimation using radio‐telemetry datasets is often hampered by small sample size. We found that combining incidental sighting data on marked individuals with radio‐telemetry data improved survival estimation by reducing the spread of 95% credible intervals in all cases with minimal and inconsistent effects on point estimates. In three of eight sub‐groups, survival estimates were only obtainable after inclusion of the incidental encounter data.

Anthropogenic subsidies to native predators can have cascading effects on sensitive prey populations, but the spatial mechanisms behind these effects are often unknown. We used a stable isotope mixing model to reconstruct spatially naïve assimilated diets of common raven (Corvus corax) chicks and then used regression analysis to investigate landscape patterns in assimilated chick diet, with particular respect to the eggs and chicks of greater sage‐grouse (Centrocercus urophasianus). Assimilated raven diets were primarily composed of mammal carrion, followed by anthropogenic food and sage‐grouse eggs and chicks. Raven diets showed landscape gradients, whereby raven chicks in nests near active greater sage‐grouse breeding leks consumed a higher proportion of sage‐grouse eggs, sage‐grouse chicks and insects in their diet and less mammal carrion. A majority of raven nests on anthropogenic nesting structures (78.7%) were within 5 km of the nearest sage‐grouse lek. Ravens nesting in high‐probability greater sage‐grouse nesting habitat consumed more insects and plants and less mammal carrion. In landscapes devoid of natural raven nesting substrates, such as our study area, anthropogenic nesting substrates can ‘anchor’ breeding ravens nearer to greater sage‐grouse leks, with concomitant increases in raven predation on greater sage‐grouse nests. Curtailment of anthropogenic nesting substrates within 5 km of a sage‐grouse lek may have a disproportionately positive impact on sage‐grouse populations. More generally, these findings highlight that the spatial arrangement of anthropogenic subsidies can result in indirect interactions between humans and predators with direct implications for predators and prey.

The generally negative effect of anthropogenic disturbance on the quality of habitats for species viability makes it a common focus of conservation assessment and prioritization efforts. Although many available spatial models and metrics (e.g., distance to or density of disturbance) characterize impact patterns of anthropogenic disturbance on the landscape, a general evaluation of model performance against empirical measurements of ecological integrity is lacking. We tested both distance‐based and disturbance‐density models in relation to ecological indicators. The models included roads, residential and commercial development, agricultural land use, mining, energy development infrastructure, and transmission structures as disturbance sources. Model parameters were based on expert input and results from the published literature. The disturbance models were tested against two disparate and independent measures of habitat quality: a floristic quality index and measures of greater sage‐grouse population integrity. Floristic quality scores were significantly lower in vegetation plots closer to disturbances in a general distance‐based disturbance model across Colorado. Although the proportion of variation in floristic quality explained by anthropogenic disturbance was relatively low (8.5–11.8%), it appeared to represent a ubiquitous baseline negative effect of proximity to anthropogenic disturbance on the quality of vegetation communities. For both distance‐ and density‐based greater sage‐grouse models, modeled disturbance indices were significantly lower (10–12 times) near active than historic leks, and numbers of males counted at leks increased significantly (3.2–3.4 times) as modeled disturbance decreased. Our findings indicate that as a general class, geospatial models can depict effects of anthropogenic disturbance on both plant communities and individual animal species. Empirical validation of disturbance models focused on other species or regions is recommended to further evaluate the utility and reliability of these methods.

Narrow endemism presents challenges to species occurrence modeling particularly when the distribution of key local habitat features changes across space and time as a function of processes operating at larger scales. One need facing conservation in such settings is a better understanding of the biogeographic dynamics of the larger features that govern occurrence of critical local habitat. The Mescalero–Monahans shinnery sands region of western North America is a dynamic landscape where sand shinnery oak interacts with wind-driven sand to establish dune habitat. This ecosystem supports several narrowly endemic dune-dwelling species including the dunes sagebrush lizard. Using near-anniversary satellite and aerial imagery from 1986, 1998, and 2011, we integrated object-based image classification and statistical analysis to develop and validate a spatially explicit estimate of the sand shinnery oak ecosystem, including dynamics associated with its attrition and emergence, at high resolution throughout an 89,849-km2 study area encompassing the range of the dunes sagebrush lizard. The spatial estimate of the distribution and extent of the sand shinnery oak soil-vegetation association validated reasonably well (overall accuracy = 0.79; sensitivity = 0.49; specificity = 0.91) and showed that the association declined 10.3 % in extent during the 25-year assessment window. The presence of sand shinnery oak, patch size, and patch isolation were dynamic across space and time; a regression model showed that smaller, isolated patches on the periphery of the system were more likely to be lost over time whereas larger, less isolated, and centrally distributed patches were more likely to persist or expand. This study details broadly applicable methods to accurately delineate landforms throughout large extents, and offers mapping tools specific to issues surrounding Mescalero–Monahans shinnery sands endemics that are readily amenable to testing, refinement, and application in efforts to focus sustainable landscape management including conservation of endemic species.

Developing sustainable rangeland management strategies requires solution-driven research that addresses ecological issues within the context of regionally important socioeconomic concerns. A key sustainability issue in many regions of the world is conserving habitat that buffers animal populations from climatic variability, including seasonal deviation from long-term precipitation or temperature averages, and that can establish an ecological bottleneck by which the landscape-level availability of critical resources becomes limited. We integrated methods to collect landscape-level animal occurrence data during severe winter conditions with estimation and validation of a resource selection function, with the larger goal of developing spatially explicit guidance for rangeland habitat conservation. The investigation involved greater sage-grouse (Centrocercus urophasianus) that occupy a landscape that is undergoing human modification for development of energy resources. We refined spatial predictions by exploring how reductions in the availability of sagebrush (as a consequence of increasing snow depth) may affect patterns of predicted occurrence. Occurrence of sage-grouse reflected landscape-level selection for big sagebrush, taller shrubs, and favorable thermal conditions and avoidance of bare ground and anthropogenic features. Refinement of spatial predictions showed that important severe winter habitat was distributed patchily and was constrained in spatial extent (7–18% of the landscape). The mapping tools we developed offer spatially explicit guidance for planning human activity in ways that are compatible with sustaining habitat that functions disproportionately in population persistence relative to its spatial extent or frequency of use. Increasingly, place-based, quantitative investigations that aim to develop solutions to landscape sustainability issues will be needed to keep pace with human-modification of rangeland and uncertainty associated with global climate change and its effects on animal populations.

Elk (Cervus elaphus) are known to shift habitat use in response to environmental modifications, including those associated with various forms of energy development. The specific behavioral responses underlying these trends, however, have not been effectively studied. To investigate such effects, we examined elk response to habitat alteration near natural gas wells in Las Animas County, Colorado, USA in 2008-2010. We created 10 1-ha openings in forests adjacent to 10 operating natural gas wells by removing standing timber in 2008, with concomitant establishment of 10 1-ha control sites adjacent to the same wells. On each site, we estimated elk use, indexed by pellet density, before and after timber removal. Concurrently, we measured plant production and cover, nutritional quality, species composition and biomass removed by elk and other large herbivores. Species richness and diversity, graminoid and forb cover, and graminoid and forb biomass increased on cut sites following tree removal. Differences were greater in 2010 than in 2009, and elk and deer removed more plant biomass in 2010 than 2009. Elk use of cut sites was 37 % lower than control sites in 2009, but 46 % higher in 2010. The initially lower use of cut sites may be attributable to lack of winter forage on these sites caused by timber removal and associated surface modification. The increased use of cut sites in 2010 suggested that elk possessed the behavioral capacity, over time, to exploit enhanced forage resources in the proximity of habitat modifications and human activity associated with maintenance of operating natural gas wells.

It is important to consider how human activity might influence behavior (e.g., space use and movement) in animals because such influences could have consequences for animal distribution or population performance. We documented and compared annual space use and daily movement patterns (i.e., movement distance and tortuosity) of female elk (Cervus elaphus) relative to human activity associated with development of energy resources in Colorado and New Mexico, USA, from 2006 to 2010. We analyzed data on 145 female elk fitted with global positioning system collars. While controlling for elevation, slope, and distance to anthropogenic features and vegetative cover, we found that proximity to the gas field generally was associated with smaller home ranges, more complex movement paths (i.e., greater tortuosity) and longer distance moved over a 3-hr period (during most seasons). Comparing elk inside of the gas field to those outside of the gas field revealed differences in space use and movement patterns at varying levels of human activity. These differences likely reflected behavior by which elk in industrial areas attempted to minimize contact with sources of human activity; whereas, elk using both industrial and nonindustrial areas exhibited behavior that could be considered escape strategies (i.e., familiarity and use of large spatial extents, increased movement distance, and linear movement paths) in response to seemingly unpredictable levels of human activity due to their use of multiple areas. Understanding such behavioral responses informs efforts to minimize effects of human activity on animal populations. © 2011 The Wildlife Society.

Prioritizing habitat for animal conservation in heterogeneous landscapes requires an understanding of where animal occurrence coincides with human influences on demographic performance. We related broad-scale patterns of occurrence with risk of mortality among female Rocky Mountain elk (Cervus elaphus) in a human-modified landscape to develop a spatially-explicit framework for animal conservation at the landscape level. Variability in the spatial pattern of elk occurrence was driven by preference for specific habitat types as well as responses to human activity. In contrast, risk of mortality was a function of human modification of the landscape with little variation explained by habitat. Proximity to industrial development was associated with increased risk of mortality whereas proximity to residences and agricultural structures was associated with decreased risk. Individual-level results revealed added complexity, whereby risk of mortality was associated with a consistent pattern of occurrence relative to industrial development, yet the association between risk and occurrence relative to structures was highly variable and likely a function of disparate land-use priorities. Approaches to managing human-mediated risk at the landscape level are most effective when they decompose human activity into constituent parts influencing risk, and when individual variation relative to the population response is investigated. Conservation interventions need to target factors that have a consistent influence across the population rather than risk uncertainty that would arise from targeting factors that influence individuals in variable or situation-specific ways. The spatial tools developed herein provide guidance for sustainable landscape planning in the study area, while the concept of linking occurrence and demographic performance within a hierarchical modeling framework has general application for animal conservation in landscapes subject to change, human-caused or otherwise.

Managing wildlife populations in areas subject to human activity is an increasingly prominent challenge. Estimating resource selection functions for species of conservation concern and developing spatially explicit maps predicting animal use across landscapes is a powerful tool for minimizing negative impacts and enhancing positive influences of human activities. However, if animals modify their selection of resources in response to humans, application of spatially explicit conservation tools based on resource selection among animals exposed to high levels of human activity risks uncertainty in the performance of such tools. This could lead to ineffective conservation action and wasted conservation dollars. To evaluate the magnitude of differences between spatial predictions based on animals exposed to different levels of human activity and develop reliable conservation tools, we used the treatment/control concept and Bayesian hierarchical discrete choice methods to model day time resource selection by female elk in a natural gas field and in areas adjacent to the gas field during winter. We found that female elk showed strong variation in resource selection patterns among years, tended to avoid roads and natural gas wells and consistently showed stronger selection for security cover, steeper slopes and greater distance to edge habitats within the gas field relative to outside of the gas field. Predictive probability of use maps based on ‘within gas field’ models classified probability of use differently in 10–55% of grid cells relative to outside of the gas field models depending on year. Conservation research and applications should consider that models based on resource selection data collected from animals subjected to human activity may not elucidate innate resource selection patterns and therefore may result in reduced effectiveness of management actions.

Common raven (Corvus corax; hereafter “raven”) populations have increased dramatically in the western United States in recent years. Ravens benefit from human resources and are known predators of other avian species. We developed a raven study to determine how primary (large‐scale, high food density, and temporally consistent) anthropogenic subsidies influenced raven movement and space use during the raven and greater sage‐grouse (Centrocercus urophasianus) breeding season and within sagebrush habitat that is commonly used by greater sage‐grouse. We also examined how movement, space use, and anthropogenic subsidization differed among ravens in different breeding statuses. We hypothesized that breeding ravens would use small areas around their nest and that nonbreeding ravens would range widely in search of food. We expected that breeding ravens would frequently use anthropogenic structures and that both breeding and nonbreeding ravens would regularly visit primary point‐source subsidies (e.g., landfills and transfer stations). Twenty ravens were captured and GPS‐tagged between 2012 and 2014. We found that breeding ravens overwhelmingly built nests on anthropogenic structures (96–100%) and subsequently used small portions of the landscape intensively. Movement of nonbreeding ravens (distance average = 2783 m/h) and ravens who had failed nests (distance average = 1357 m/h) ranged widely. Breeding ravens visited highways and railroads inversely proportional to the distance between the nest and the nearest highway/railroad. Nonbreeding ravens regularly visited landfills and transfer stations, but breeding ravens did not (

Rapid expansion of energy development in some portions of the Intermountain West, USA, has prompted concern regarding impacts to declining greater sage-grouse (Centrocercus urophasianus) populations. We used retrospective analyses of public data to explicitly investigate potential thresholds in the relationship between lek attendance by male greater sage-grouse, the presence of oil or gas wells near leks (surface occupancy), and landscape-level density of well pads. We used generalized linear models and generalized estimating equations to analyze data on peak male attendance at 704 leks over 12 years in Wyoming, USA. Within this framework we also tested for time-lag effects between development activity and changes in lek attendance. Surface occupancy of oil or gas wells adjacent to leks was negatively associated with male lek attendance in 5 of 7 study areas. For example, leks that had L oil or gas well within a 0.4-km (0.25-mile) radius encircling the lek had 35-91% fewer attending males than leks with no well within this radius. In 2 of these 5 study areas, negative effects of well surface occupancy were present out to 4.8 km, the largest radius we investigated. Declining lek attendance was also associated with a higher landscape- level density of well pads; lek attendance at well-pad densities of 1.54 well pads/km 2 (4 well pads/mile 2 ) ranged from 13% to 74% lower than attendance at unimpacted leks (leks with zero well pads within 8.5 km). Lek attendance at a well-pad density of 3.09 well pads/km 2 (8 well pads/mile 2 ) ranged from 77% to 79% lower than attendance at leks with no well pad within 8.5 km. Further, our analysis of time-lag effects suggested that there is a delay of 2-10 years between activity associated with energy development and its measurable effects on lek attendance. These results offer new information for consideration by land managers on spatial and temporal associations between human activity and lek attendance in sage-grouse, and suggest that regional variation is an important consideration in refining existing management strategies. Development of energy resources including oil and natural gas has accelerated in the past decade in portions of the Intermountain West, USA. The Wyoming Oil and Gas Conservation Commission (WOGCC) reported that the number of producing wells in the 25 largest natural gas fields in the state increased from 7,907 wells in 2000 to 25,297 wells

Introduction Incorporating information on animal behavior in resource-based predictive modeling (e.g., occurrence mapping) can elucidate the relationship between process and spatial pattern and depict habitat in terms of its structure as well as its function. In this paper, we assigned location data on brood-rearing greater sage-grouse (Centrocercus urophasianus) to either within-patch (encamped) or between-patch (traveling) behavioral modes by estimating a movement-based relative displacement index. Objectives were to estimate and validate spatially explicit models of within- versus between-patch resource selection for application in habitat management and compare these models to a non-behaviorally adjusted model. Results A single model, the vegetation and water resources model, was most plausible for both the encamped and traveling modes, including the non-behaviorally adjusted model. When encamped, sage-grouse selected for taller shrubs, avoided bare ground, and were closer to mesic areas. Traveling sage-grouse selected for greater litter cover and herbaceous vegetation. Preference for proximity to mesic areas was common to both encamped and traveling modes and to the non-behaviorally adjusted model. The non-behaviorally adjusted map was similar to the encamped model and validated well. However, we observed different selection patterns during traveling that could have been masked had behavioral state not been accounted for. Conclusions Characterizing habitat that structured between-patch movement broadens our understanding of the habitat needs of brood-rearing sage-grouse, and the combined raster surface offers a reliable habitat management tool that is readily amenable to application by GIS users in efforts to focus sustainable landscape management.

Hydrologically isolated forest pools, both vernal and permanent, are receiving increased attention in conservation because they often provide fishless habitats for forest-dwelling amphibians, reducing risk of predation to eggs and larvae. However, clarifying conservation value of such pools requires determination of whether the species they contribute to local biodiversity are unique or also present in other nearby wetlands such as freshwater marshes. We compared composition of amphibian communities in clustered pools to that of both spatially isolated pools and freshwater marshes in Illinois (USA) from 2008 to 2010 to determine (1) effects of clustering on community structure, species richness, and occupancy dynamics; (2) unique contributions of forest pools (six clustered and three isolated pools) to amphibian diversity compared to marshes (n = 6); and (3) species-specific probabilities of occupancy by wetland type. Amphibian communities differed among wetland categories, with community similarity in the same year reduced 38% by differences between marshes, clustered pools, and isolated pools. Species richness was similar in clustered pools and marshes, but lower in isolated pools. Clustered pools contributed more species (n = 10) than marshes (n = 7) or isolated pools (n = 4). Anuran species had higher probability of greater relative abundance and salamanders had greater probability of encounter at clustered pools than at isolated pools, and probabilities of species-specific site occupancy were lowest at isolated pools. Wildlife managers in Midwest USA can better understand species-specific occupancy dynamics of amphibians in different wetland categories through this analysis and can optimize local amphibian species richness through conservation of clusters of forest pools.

A community-level approach to identify important brood habitats of greater sage-grouse (Centrocercus urophasianus) may prove useful in guiding management actions because it acknowledges that important habitat components are not ecologically independent from each other. We used principal components analysis to combine insect and vegetation variables into community gradients and used logistic regression to link these components with brood survival and occurrence. We found that brood success was higher when broods occurred in specific insect-vegetation community types. A relationship between brood occurrence and insect-vegetation gradients was not apparent. The high resolution of the data and the solid validation performance suggest that identifying insect-vegetation communities is a promising technique for quantifying sage-grouse habitat relationships. This approach offers land managers a way of identifying important sage-grouse habitat that is ecologically aligned with traditional community-level land management practices (e.g., fire management, rotational grazing, vegetation manipulation, etc.).

Mule deer ( Odocoileus hemionus ) are known to shift habitat use in response to environmental modifications, including those associated with energy development. Their specific behavioral responses, however, and capacities to habituate to particular aspects of energy development have not been effectively studied. We examined mule deer response to habitat alteration near natural gas wells in Las Animas County, Colorado, USA in 2008—2010, an area experiencing development for extraction of natural gas. We created 10-1 ha openings in forests adjacent to 10 wells by removing standing trees in 2008, with concomitant establishment of 10 1-ha control sites adjacent to the same wells. On each site, we estimated deer use, indexed by pellet density, before and after tree removal. Concurrently, we measured plant production, cover, nutritional quality, species composition and biomass removed by deer and other large herbivores. Species richness and diversity and graminoid and forb cover and biomass increased on cut sites following tree removal. Use increased following tree removal on cut and control sites, but was greater on cut sites in 2010. Herbivores removed negligible quantities of vegetation on control sites in both years, suggesting that control sites may have been used primarily for concealment. Mule deer demonstrated the behavioral capacity to habituate to habitat modifications and other environmental changes associated with development for the extraction of energy. Managing forage and habitat availability appears to have the potential to affect the type of response and degree of habituation by mule deer to such development.

BackgroundBalancing animal conservation and human use of the landscape is an ongoing scientific and practical challenge throughout the world. We investigated reproductive success in female greater sage-grouse (Centrocercus urophasianus) relative to seasonal patterns of resource selection, with the larger goal of developing a spatially-explicit framework for managing human activity and sage-grouse conservation at the landscape level.Methodology/principal findingsWe integrated field-observation, Global Positioning Systems telemetry, and statistical modeling to quantify the spatial pattern of occurrence and risk during nesting and brood-rearing. We linked occurrence and risk models to provide spatially-explicit indices of habitat-performance relationships. As part of the analysis, we offer novel biological information on resource selection during egg-laying, incubation, and night. The spatial pattern of occurrence during all reproductive phases was driven largely by selection or avoidance of terrain features and vegetation, with little variation explained by anthropogenic features. Specifically, sage-grouse consistently avoided rough terrain, selected for moderate shrub cover at the patch level (within 90 m(2)), and selected for mesic habitat in mid and late brood-rearing phases. In contrast, risk of nest and brood failure was structured by proximity to anthropogenic features including natural gas wells and human-created mesic areas, as well as vegetation features such as shrub cover.Conclusions/significanceRisk in this and perhaps other human-modified landscapes is a top-down (i.e., human-mediated) process that would most effectively be minimized by developing a better understanding of specific mechanisms (e.g., predator subsidization) driving observed patterns, and using habitat-performance indices such as those developed herein for spatially-explicit guidance of conservation intervention. Working under the hypothesis that industrial activity structures risk by enhancing predator abundance or effectiveness, we offer specific recommendations for maintaining high-performance habitat and reducing low-performance habitat, particularly relative to the nesting phase, by managing key high-risk anthropogenic features such as industrial infrastructure and water developments.

Development and extraction of resources such as oil and gas has directly and indirectly reduced available habitat to wildlife through changes in behavior and resource use. To assess how elk (Cervus elaphus) and deer (Odocoileus spp.) were spatially distributed relative to roads and coal-bed natural gas well pads, we collected pellet group data during 2 summers in south-central Colorado. We used generalized linear mixed models to assess the relative probability of use of elk and deer in relation to roads and well pads. We found relative probability of use was positively associated with distance from roads, indicating greater use of areas farther away from roads. Relative probability of use was negatively associated with distance to well pads, potentially as a result of plant phenology and reseeding in disturbed areas around well pads. Other factors such as elevation, slope and vegetative security cover also influenced elk and deer spatial distributions. Based on these data, it appears resource use may be driven by forage and security cover more than disturbance features. Pellet group surveys appear to be an appropriate technique for evaluating resource use of populations across large spatial extents when logistical and financial constraints limit the use of more advanced technology such as very high frequency and global positioning system collars.

BackgroundConserving animal populations in places where human activity is increasing is an ongoing challenge in many parts of the world. We investigated how human activity interacted with maternal status and individual variation in behavior to affect reliability of spatially-explicit models intended to guide conservation of critical ungulate calving resources. We studied Rocky Mountain elk (Cervus elaphus) that occupy a region where 2900 natural gas wells have been drilled.Methodology/principal findingsWe present novel applications of generalized additive modeling to predict maternal status based on movement, and of random-effects resource selection models to provide population and individual-based inference on the effects of maternal status and human activity. We used a 2×2 factorial design (treatment vs. control) that included elk that were either parturient or non-parturient and in areas either with or without industrial development. Generalized additive models predicted maternal status (parturiency) correctly 93% of the time based on movement. Human activity played a larger role than maternal status in shaping resource use; elk showed strong spatiotemporal patterns of selection or avoidance and marked individual variation in developed areas, but no such pattern in undeveloped areas. This difference had direct consequences for landscape-level conservation planning. When relative probability of use was calculated across the study area, there was disparity throughout 72-88% of the landscape in terms of where conservation intervention should be prioritized depending on whether models were based on behavior in developed areas or undeveloped areas. Model validation showed that models based on behavior in developed areas had poor predictive accuracy, whereas the model based on behavior in undeveloped areas had high predictive accuracy.Conclusions/significanceBy directly testing for differences between developed and undeveloped areas, and by modeling resource selection in a random-effects framework that provided individual-based inference, we conclude that: 1) amplified selection or avoidance behavior and individual variation, as responses to increasing human activity, complicate conservation planning in multiple-use landscapes, and 2) resource selection behavior in places where human activity is predictable or less dynamic may provide a more reliable basis from which to prioritize conservation action.

Connectivity of animal populations is an increasingly prominent concern in fragmented landscapes, yet existing methodological and conceptual approaches implicitly assume the presence of, or need for, discrete corridors. We tested this assumption by developing a flexible conceptual approach that does not assume, but allows for, the presence of discrete movement corridors. We quantified functional connectivity habitat for greater sage-grouse (Centrocercus urophasianus) across a large landscape in central western North America. We assigned sample locations to a movement state (encamped, traveling and relocating), and used Global Positioning System (GPS) location data and conditional logistic regression to estimate state-specific resource selection functions. Patterns of resource selection during different movement states reflected selection for sagebrush and general avoidance of rough topography and anthropogenic features. Distinct connectivity corridors were not common in the 5,625 km(2) study area. Rather, broad areas functioned as generally high or low quality connectivity habitat. A comprehensive map predicting the quality of connectivity habitat across the study area validated well based on a set of GPS locations from independent greater sage-grouse. The functional relationship between greater sage-grouse and the landscape did not always conform to the idea of a discrete corridor. A more flexible consideration of landscape connectivity may improve the efficacy of management actions by aligning those actions with the spatial patterns by which animals interact with the landscape.

We investigated generality of resource-based models of predicted occurrence as part of an effort in spatial prioritization of habitat for conservation in shrub-steppe landscapes of western North America. Using GPS telemetry data on the greater sage-grouse (Centrocercus urophasianus), we investigated whether spatial models developed in particular regions of Wyoming, USA were generalizable to other portions of the state, whether generality versus region-specificity were mediated by behavior state, and why models were either general or region-specific (i.e., what factors constrained versus promoted generality). The behavior states we examined were nest-site selection, and resource selection during nesting off-bouts. We tested generality by developing models within the region at which location data were collected, applying models across regions (3 different hydrologic basins), using independent location data to validate, and subsequently analyzing a validation parameter (Spearman's rho) in a beta regression m...

Context Long-term studies of large, vertebrate mammals using capture–recapture data are scarce, even though long-term ecological studies are requisite to understanding quantitative genetics and evolutionary processes that can be applied as part of management programs. Aims Objectives were to (1) partition components of variation in body mass to understand the differential effects of environmental variation on the sexes during ontogeny, to better prescribe habitat-improvement projects, and (2) estimate repeatability to assess potential for selection on body mass. Methods We used a 23-year dataset (1983–2005) of capture–recapture records of wild white-tailed deer (Odocoileus virginianus) to estimate components of variance and repeatability of body mass. We used an animal-model approach that employed the use of general linear mixed models and restricted maximum likelihood to adjust for the effects of age (i.e. fixed effect), and to partition the total phenotypic variance into among-individual (i.e. the deer), permanent environmental (i.e. year of birth) and temporary environmental (i.e. year of measurement and residual) effects (all modelled as random effects). Key results We found that body mass increased with age in both sexes, repeatability of body mass was 0.595 for females and 0.716 for males, and among-individual variation was more influential on body mass than were permanent and temporary environmental effects combined. Year of birth was more important in males than females, but changed during the course of ontogeny for both sexes. Year of measurement did not influence post-rut body mass in males, but did contribute to variation in body mass of females. Conclusions These long-term data offer insights into the sources of variation that influence body mass of deer, which can be used to understand how environmental sources of variation influence phenotypic traits, and for developing management plans and making selection decisions. Implications Knowledge of repeatability (as an upper limit to heritability) can be used to make management decisions related to selection, culling and breeding, whereas understanding environmental effects can lead to better management recommendations (e.g. habitat-improvement projects).

Developing strategies for sustainable management of landscapes requires research that bridges regionally important ecological and socioeconomic issues, and that aims to provide solutions to sustainability problems. We integrated Global Positioning Systems (GPS) telemetry and statistical modeling to quantify hierarchical spatial and temporal components of occurrence among greater sage-grouse (Centrocercus urophasianus; n = 87), a species of conservation concern, with the larger goal of developing spatially-explicit guidance for conservation of important winter habitat in a Wyoming, USA landscape undergoing development for energy resources. The pattern of occurrence at the landscape level (second-order) and within seasonal use areas (third-order) included selection for shrub vegetation with a prominent sagebrush (Artemisia spp.) component, and avoidance of rough terrain, mesic areas, and human activity. A change in resource selection behavior across the diel cycle was not an apparent component of the higher-order selection process; however, at the finer scale of investigation sage-grouse shifted behavior across the diel cycle in ways likely related to risk aversion or maintaining a favorable thermal environment (i.e., day-time-only avoidance of natural gas wells and night-time-only selection for taller shrubs). At both spatial scales there was considerably more variation among individuals in the sign of their association with anthropogenic features than with vegetation and terrain. The final spatially-explicit model, which depicted lower-order selection (local, patch-level, and seasonal use area) across the diel cycle constrained by selection processes at a higher order (second-order), validated well, offering specific guidance for managing human activity and sage-grouse conservation in the study area, and general guidance in developing sustainable landscape management strategies when animal occurrence reflects multiple spatial and temporal processes.

Context Many ungulate species exhibit strong site fidelity to previously established areas, particularly females. However, development of the landscape may cause animals to shift their distribution to more secure areas. Aims To determine range use dynamics (i.e. size and overlap of core areas and home ranges) of female elk (Cervus elaphus) relative to land development features (e.g. roads, well pads, buildings, developments, towns, etc.) after controlling for environmental features (i.e. forest cover). Methods During the four-year study, we fitted elk (n = 165) with GPS collars annually and programmed collars to attempt one location fix every 3 h (eight locations per day) for one year. Females (n = 18) were subsequently recaptured and refitted with GPS collars to provide range use dynamics of individual elk over two to three years. We calculated sizes of core areas and home ranges using adaptive kernel estimators, overlap between annual ranges, and establishment of ranges relative to land development. Key results Overlap of annual core areas (48.6%) and home ranges (67.9%) was high despite annual increases in land development. Sizes of core areas and home ranges and annual overlap (i.e. site fidelity) were negatively influenced by land development after controlling for forest cover. Conclusions These data reveal that female elk show high levels of site fidelity even in the presence of increasing annual land development. Females did not appear to abandon previously established areas, but used ranges in a manner that minimised interaction with development within these areas based on reductions in range use size and fidelity as land development increased. Implications To help mitigate impacts on elk, land development should be minimised and large areas of forest protected so elk can avoid areas associated with human activity.

Animal populations are becoming increasingly exposed to human activity as human populations expand and demand for energy resources (e.g., coal, oil and natural gas) increases. We initiated this study to document survival and cause-specific mortality patterns of female Rocky Mountain elk (Cervus elaphus) exposed to increasing levels of human activity. We fitted 184 females with VHF or GPS collars over 4 years and used the Kaplan–Meier survival estimator to calculate annual survival rates. We used multinomial logistic regression to assess differences in cause-specific mortality and generalized linear mixed models to determine how probability of survival was structured during hunting season; both analyses examined a suite of 5 covariates (i.e., age, year, extent of space use, cover, and human footprint) as potentially influencing cause-specific mortality and survival probability. Annual probability of survival averaged 0.8 (±0.02 SE) over 4 years but averaged 0.91 (±0.03 SE) when harvest mortality was excluded, which was the most significant source of mortality in most years (\( \bar{x} = 0.13 \pm 0.02\,{\text{SE}} \)). We found no difference between cause-specific mortality sources relative to elk that survived during the hunting season (χ102 = 5.79, P = 0.832). The probability of a female surviving during hunting season was negatively influenced by age, year, extent of space use, cover, and human footprint. We found evidence that human activity may have influenced annual rates of natural survival (i.e., exclusive of hunting mortality) and probability of survival during the hunting season. We note that this study occurred largely on privately owned and managed residential and ranch land and focused on female elk; we acknowledge that survival rate and cause-specific patterns of mortality may vary as a function of land ownership (private vs. public), demographic status, and management and harvest practices. While temporal and spatial scales of 1 week may be sufficient to describe patterns of direct mortality during hunting season, broad temporal or spatial scale analyses may be needed to address natural mortality during other seasons.

Ground-nesting birds experience high levels of nest predation. However, birds can make selection decisions related to nest site location and characteristics that may result in physical, visual, and olfactory impediments to predators. We studied daily survival rate [DSR] of greater sage-grouse (Centrocercus urophasianus) from 2008 to 2010 in an area in Wyoming experiencing large-scale alterations to the landscape. We used generalized linear mixed models to model fixed and random effects, and a correlation within nesting attempts, individual birds, and years. Predation of the nest was the most common source of nest failure (84.7%) followed by direct predation of the female (13.6%). Generally, landscape variables at the nest site (≤ 30 m) were more influential on DSR of nests than features at larger spatial scales. Percentage of shrub canopy cover at the nest site (15-m scale) and distances to natural gas wells and mesic areas had a positive relationship with DSR of nests, whereas distance to roads had a negative relationship with DSR of nests. When added to the vegetation model, maximum wind speed on the day of nest failure and a 1-day lag in precipitation (i.e., precipitation the day before failure) improved model fit whereby both variables negatively influenced DSR of nests. Nest site characteristics that reduce visibility (i.e., shrub canopy cover) have the potential to reduce depredation, whereas anthropogenic (i.e., distance to wells) and mesic landscape features appear to facilitate depredation. Last, predators may be more efficient at locating nests under certain weather conditions (i.e., high winds and moisture).