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Grazing by livestock, particularly cattle (Bos spp.), is the dominant land use across North American rangelands and often co-occurs in habitats used by wildlife. Deer (Odocoileus spp.) are an ecologically and economically important native wildlife species in North America. Sustainable management and profitable economic returns require an understanding of the factors driving cattle-deer compatibility. Cattle are compatible with deer when cattle grazing does not negatively impact deer or their habitat requirements (food, cover, and space). We reviewed 2,685 publications on cattle-deer interactions across North American ecosystems to assess the compatibility of these two important genera. We extracted data from 85 of the publications, years ranged from 1930–2015, that met criteria for quantifying cattle-deer diet overlap, and cattle effects on deer food, cover, and space. We determined that cattle-deer compatibility across North American ecosystems is dictated: mostly by geographic region; followed by cattle stocking rate and season; and marginally by soil texture. Cattle and deer were compatible across North American ecosystems when cattle stocking rate was less than 0.12−0.17 AUY ha−1. Cattle-deer diet overlap was lowest during summer and autumn. Although, cattle had the greatest potential to decrease forbs in the northeastern forested ecoregion on clay soils during autumn. Cattle had little measurable effect on habitat variables important to deer in open North American ecoregions dominated by herbaceous vegetation. In contrast to rangelands, cattle had the greatest potential to adversely impact deer food, cover, and use of space in forest-dominated ecoregions in North America. However, observations in eastern forested ecoregions only represented 6−16% our data sets. Our review reveals a range of conservative cattle stocking rates (0.12−0.17 AUY ha−1) that will have minimal impact on deer using rangelands, and that stocking rates in forested ecoregions may need to be reduced further to minimize impacts to deer and their habitat requirements.

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 increased use of antler restrictions by state game agencies has led to a focus on antlers by the hunting public, particularly the potential for an association between genetics and antler characteristics. We analyzed microsatellite data from 1231 male white-tailed deer (Odocoileus virginianus) from three states (Oklahoma, Mississippi, and Texas) within USA to determine if genetic relatedness, internal relatedness (IR), homozygosity weighted by locus (HL), or correlations among uniting gametes (Fis) influenced total antler points, antler score, non-typical points or antler malformations. Within each location, deer in the lower and upper quartile intervals for number of antler points and score were unrelated (95% CI included 0 or was &lt, 0) and relatively heterozygous for four measures of inbreeding. Antler score and points were positively influenced by age but negatively influenced by IR and HL, except for antler score in Mississippi. Relatedness, HL, IR and Fis did not differ between groups of deer with and without antler malformations. Perceived differences in antler quality do not appear to be affected by heterozygosity or a result of close inbreeding because we found deer were unrelated and measures of inbreeding and genome-wide heterozygosity were not correlated with antler characteristics.

Wild pig (Sus scrofa) populations in the United States are expanding and increasing in distribution and abundance and are known to reservoir a variety of pathogens that can have economic and agricultural impacts. We examined wild pigs for exposure to Brucella spp. and Francisella tularensis from Oklahoma and Texas to determine their potential role as a regional reservoir for these pathogens since wild pigs co‐occur with livestock, especially on rangelands in this region. Antibodies to Brucella spp. and F. tularensis were found in every location sampled and during multiple years. Overall, wild pigs had a 12.5% prevalence of Brucella spp. and a 14.8% prevalence of F. tularensis in this study. Wild pig prevalence of Brucella spp. was 43 times higher in southcentral Oklahoma compared to previously published results. Understanding and monitoring regional disease prevalence rates in wild pigs are necessary, especially on rangelands managing for livestock that may be susceptible to these diseases.

This article is protected by copyright. All rights reserved. With the accelerating pace of global change, it is imperative that we obtain rapid inventories of the status and distribution of wildlife for ecological inferences and conservation planning. To address this challenge, we launched the SNAPSHOT USA project, a collaborative survey of terrestrial wildlife populations using camera traps across the United States. For our first annual survey, we compiled data across all 50 states during a 14-week period (17 August - 24 November of 2019). We sampled wildlife at 1509 camera trap sites from 110 camera trap arrays covering 12 different ecoregions across four development zones. This effort resulted in 166,036 unique detections of 83 species of mammals and 17 species of birds. All images were processed through the Smithsonian's eMammal camera trap data repository and included an expert review phase to ensure taxonomic accuracy of data, resulting in each picture being reviewed at least twice. The results represent a timely and standardized camera trap survey of the USA. All of the 2019 survey data are made available herein. We are currently repeating surveys in fall 2020, opening up the opportunity to other institutions and cooperators to expand coverage of all the urban-wild gradients and ecophysiographic regions of the country. Future data will be available as the database is updated at eMammal.si.edu/snapshot-usa, as well as future data paper submissions. These data will be useful for local and macroecological research including the examination of community assembly, effects of environmental and anthropogenic landscape variables, effects of fragmentation and extinction debt dynamics, as well as species-specific population dynamics and conservation action plans. There are no copyright restrictions; please cite this paper when using the data for publication. Publisher PDF

Fencing wildlife populations can aid wildlife management goals, but potential benefits may not always outweigh costs of confinement. Population isolation can erode genetic diversity and lead to the accumulation of inbreeding, reducing viability and limiting adaptive potential. We used microsatellite and mitochondrial DNA data collected from 640 white-tailed deer confined within a 1184 ha fence to quantify changes in genetic diversity and inbreeding over the first 12 years of confinement. Genetic diversity was sustained over the course of the study, remaining comparable to unconfined white-tailed deer populations. Uneroded genetic diversity suggests that genetic drift is mitigated by a low level of gene flow, which supports field observations that the fence is not completely impermeable. In year 9 of the study, we observed an unexpected influx of mtDNA diversity and drop in inbreeding as measured by FIS. A male harvest restriction imposed that year increased male survival, and more diverse mating may have contributed to the inbreeding reduction and temporary genetic diversity boost we observed. These data add to our understanding of the long-term impacts of fences on wildlife, but also highlight the importance of continued monitoring of confined populations.

Recreational hunters have largely replaced natural predators of white-tailed deer ( Odocoileus virginianus ) across much of North America; thereby, providing the greatest form of risk (both direct and indirect) to survival. On a 1861-ha property in Oklahoma, USA, we evaluated how controlled hunting influenced movement behaviour (using movement rate [m/h] and relative displacement index [%]) of 37 adult (≥2.5 years) male deer at three risk treatment levels (i.e., control = no risk; low-risk = 1 hunter/101 ha; and high-risk = 1 hunter/30 ha), two temporal periods of risk (i.e., diurnal [06:00–18:00] and nocturnal [18:00–06:00]), and across time (36 days); time was modelled as a continuous variable that covered five risk exposure periods (risk present or absent in brackets; i.e., pre-season [absent], scout [present], pre-hunt [absent], hunt [present], and post-hunt [absent]). Movement rate (m/h) decreased over time for all risk treatment levels and temporal period of risks; however, the magnitude (i.e., slope) of decrease varied across treatments. The magnitude of decrease in movement rate was similar for control and low risk treatments during diurnal and nocturnal periods, but was different between low and high risk, and high risk and control treatments. Relative displacement (%) of deer was greatest at the start of the study, decreasing during the study finally resulting in displacement values being three times less after hunting season. Deer responded to the presence of hunters on the landscape by adapting movement strategies both spatially and temporally to avoid potential contact with hunters. During the study, deer reduced movements and used smaller areas more intensively, as indicated by the relative displacement index. Reducing movement or space use may lead to lower detection of deer by hunters, thus increasing the probability of survival through reduced harvest. Understanding deer behavioural responses to hunters (and at different levels of risk) could be used to facilitate or reduce harvest based on population management objectives.

Wild pigs ( Sus scrofa ) are causing increasing ecologic and economic damage at a global scale. Because wild pigs can carry ≥65 diseases that affect livestock, their widespread expansion threatens native wildlife and livestock. We screened wild pigs from south-central Oklahoma, US for antibodies against Brucella abortus , pseudorabies virus (PRV), and porcine reproductive and respiratory syndrome virus (PRRS). These pathogens were chosen because they are part of eradication programs in the US and could have large economic impacts on domestic livestock if transmitted from wild animals. We tested 282 serum samples during spring 2010 (n=149) and 2011 (n=133) and found an overall exposure rate to PRV of 24.1% (n=68); PRV was detected at two of three study sites. Two wild pigs had detectable antibody to B. abortus , and one had detectable antibody to PRRS. On average, 27% of wild pigs within a sounder were positive for PRV antibody, with 44% of the sounders (16/36) having at least one positive individual. These data highlight that wild pigs could carry pathogens that affect domestic livestock. Because the US is free of these pathogens in commercial livestock operations, continued surveillance and vaccination of domestic livestock are needed. Commercial livestock producers at the wildlife-livestock interface may benefit from spatial prioritization of risk zones to facilitate strategic control efforts.

The ability to develop large antlers in penned deer (Odocoileus sp.) has increased interest in releasing pen-raised deer to increase antler size of wild populations. We used a model based on population genetic theory with random removal as the form of population control and either 10% emigration and 10% immigration to represent a free-ranging population (Free Range) or with no egress or ingress to represent a fenced property (Fenced). We compared results with a livestock model with no egress or ingress and selective removal of smaller antlered males as the form of population control (Best Case). We modeled release of fawns with an antler distribution averaging 200 gross Boone and Crockett (BC a 25% replacement increased score by 18. The Best Case Model increased score by 33 at 25% replacement. The cost for each unit increase in score was US$115,000 in a free-ranging population, US$75,000 in a fenced population, and US$33,000 in the best case. Our results suggest that altering genetic composition of white-tailed deer populations is not feasible for free-ranging populations and very costly within fenced populations. © 2016 The Authors. Wildlife Society Bulletin published by Wiley Periodicals, Inc. on behalf of The Wildlife Society.

Switchgrass (Panicum virgatum L.) is a native perennial grass species with great potential for bioenergy and forage. However, knowledge about its genetics and biology related to breeding is still in its infancy. Studying the diversity of switchgrass germplasm will shed light on variability, response to environmental conditions, adaptability, breeding, etc. Thirty‐six switchgrass accessions/cultivars were used to study the ecotypic and genotypic effects on regrowth, heading date, and vegetative growth period. The R‐360 honeycomb design was used for planting these accessions in 2007. Data on regrowth and heading dates were recorded in 2008, 2010, and 2011. Vegetative growth period was calculated by subtracting the regrowth date from the heading date. It was found that the lowland started regrowing earlier (77 ± 0.4 days of the year, DOY) than the upland ecotype (82 ± 0.3 DOY). The upland had earlier heading date (160 ± 0.4 DOY) than the lowland ecotype (173 ± 0.5 DOY). Vegetative growth period was about 18 days longer in the lowland (89 ± 0.6 days) than the upland ecotype (71 ± 0.4 days). For switchgrass (i.e., all accessions), biomass yield was related positively to growth period and heading date; however, biomass was only weakly related to regrowth. Therefore, when targeting biomass in the breeding program, growth period may be a quick and reliable reference in both ecotypes to quickly estimate biomass potential while regrowth and heading date may be better used as a parameter for accessions within an ecotype.

Development for wind energy is increasing rapidly across the United States, particularly in Wyoming, despite a general lack of information on the potential interaction development could have on wildlife species. Therefore, knowledge of the space use and movement patterns of individuals can help define spatial distributions and management unit boundaries for populations prior to development. Such knowledge can also be used as baseline data from which to assess any future impacts on animal populations. We investigated the spatial ecology of female mule deer (Odocoileus hemionus; n = 18) equipped with global positioning system collars from 23 February 2011 to 15 January 2012 in an area along the Wyoming-Colorado border that has been proposed for wind energy development. The objectives of this study were to collect predevelopment baseline estimates of annual and seasonal home-range and core area size and fidelity, movement between seasonal ranges, changes in the use of elevation, and movement patterns at 2 temporal resolutions (i.e., within-season diel patterns and year-round diurnal and nocturnal movements by week). Annual size of home ranges averaged 2495 ha (SE = 121), whereas size of core areas averaged 310 ha (SE = 30). Seasonal site fidelity was substantial (81.1%, SE = 5.7) between successive cool-season ranges. Migration distances between cool- and warm-season home ranges were minimal (spring migration = 1319 m; autumn migration = 1342 m). Deer exhibited crepuscular movement patterns (peaks near 06:00 and 18:00) during the warm season but showed a diurnal movement pattern dur- ing the cool season (peak from 06:00 to 15:00). Partuition influenced movement during the warm season; movement was much reduced during a period from mid-June to mid-July. Deer in this population appear to be year-round residents that exhibit strong seasonal and annual fidelity to previously established ranges and modify movement patterns in rela- tion to general changes in environmental conditions (e.g., snow). These findings can be used to define seasonally impor- tant ranges and formulate boundaries and sizes of game management units. Understanding fine-scale temporal move- ment allows the development of strategies that could minimize disturbance to deer while allowing for development or recreation.

Areas identified as winter range are important seasonal habitats for mule deer ( Odocoileus hemionus ) because they can moderate overwinter mortality by providing thermal cover and forage. Therefore, identifying seasonally important resources is a conservation priority, especially when sensitive areas are proposed for development. We used data collected from global positioning system (GPS) collars fitted on female mule deer ( n = 19; one location every 3 h) to identify resources important during winter (23 February 2011–30 April 2011; 1 November 2011–15 January 2012) in a region spanning southern Wyoming and northern Colorado that has been proposed for wind energy development. The study period included portions of two consecutive winters but were pooled for analysis. We used methods to account for GPS biases, fractal analyses to determine perceived spatial scale, and discrete choice models and conditional logistic regression to assess resource selection prior to development (i.e., baseline data). Resource selection by female mule deer revealed similar patterns between active (0600–1800 hours) and nonactive (2100–0300 hours) periods. Deer selected most strongly for proximity to rock outcrops and shrubland and average values of slope. Deer tended to avoid roads and grasslands; all other landscape features had minimal influence on resource selection (hazard ratios near, or overlapping, 1). Using the fixed-effects coefficient estimates, we developed two spatially explicit maps that depicted probability of mule deer occurrence across the landscape. Based on an independent validation sample, each map (active and nonactive) validated well with a greater percentage of locations occurring in the two highest probability of use bins. These maps offer guidance to managing mule deer populations, conserving important seasonal habitats, and mitigating development (e.g., wind energy) in areas identified as important to mule deer.

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.

Most Americans support legal hunting for food or as a population management tool, but there are strong concerns about illegal hunting activities such as poaching. Poaching may negatively impact animal populations by causing local extinctions, reducing genetic variability, reducing trophy size and hunting opportunities, and altering sex ratios and age structures. One approach to help mitigate poaching is to identify patterns of reported poaching activity and to document poaching arrests to help facilitate the efficiency of future surveillance for poachers. Our goal for this manuscript was to analyze temporal, spatial, and environmental patterns associated with poaching activity reported for white-tailed deer (Odocoileus virginianus) in Fayette County, Iowa, USA, based on reports of poaching activity. We analyzed data from 67 reported poaching events from 2000 to 2009 and correlated these events with temporal, spatial, and environmental variables to determine trends in illegal hunting behavior. We found that poachers preferred to be active during the evening in mid- to late autumn (primarily Oct–Dec), on days with no precipitation and high visibility, and in areas next to roads, forests, and riparian cover types containing variable topography. We used these results to develop a spatially explicit map depicting hotspots of poaching activity. By identifying patterns of poaching behavior and spatially explicit prediction maps, conservation officers will be able to survey for poaching activity more efficiently. © 2012 The Wildlife Society.

Selective harvesting in wild deer (Odocoileus spp.) populations is a common practice that may influence antler size. However, in free-ranging populations, response due to selection is unknown or difficult to quantify because antlers are influenced by nutrition and population demographics. We used quantitative genetic models to predict how white-tailed deer (O. virginianus) antlers would respond to selection and what variables (i.e., population size, age structure, mating ratio, and heritability) most affected antler size. We validated our quantitative genetics program by comparing model results with a population of deer used for controlled breeding experiments; modeled antler points (AP) and score increased (2.2–4.3 AP and 48.5–97.7 cm, respectively) after 8 years of selection, similar to observed increases in AP (3.2) and score (92.3 cm) from the controlled population. In modeled free-ranging populations, mating ratio, age structure, and heritability were more important in influencing antler size than size of the population. However, response to selection in free-ranging populations was lower (0.1–0.9 AP) than controlled breeding populations even after 20 years of selection. These results show that selective harvesting of free-ranging white-tailed deer may be inefficient to change population-level genetic characteristics related to antler size. Response of antlers in free-ranging deer will be less than controlled populations, and possibly modeled free-ranging simulations, because individual reproductive success of males is lower, breeding is done by a large group of males, and reproductive and survival rates are lower. These factors, and others, reduce the amount of improvement that can be made to antlers due to selection. Therefore, selective harvesting in free-ranging populations should be justified for managing population demographics and dynamics, but not for changing the genetic characteristics of populations. © 2011 The Wildlife Society.

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.

We modeled how variation in size of home ranges and annual movements of white-tailed deer (Odocoileus virginianus) in southern Texas altered ability to manage deer within various sizes of management units and discussed implications for spread of disease. The percentage of adult (≥3.5 years) males remaining on management units varied 98% of males would use management units of 1,000 km2 because their use of space would not result in use of adjoining management units. Migration of deer in northern latitudes resulted in 20% of the population using management units of 1,000 km2, which potentially could expose large areas (>25,000 km2) to disease because a greater percentage of deer would use adjoining management units compared to deer in southern latitudes. Our results are useful in determining...

It is often difficult to test hypotheses about how and why animal movement responds to environmental conditions, and at what spatial scales movement decisions are made, all of which are critical for sound management. We used fractal dimension (D) as a measure of tortuosity because it described animal movement patterns and was useful for testing hypotheses about effects of sex, home-range size, monthly rainfall, and reproductive phase on movement paths and for detecting changes in movement patterns of animals across a range of movement distances. We captured and fitted 33 (18 females and 15 males) white-tailed deer (Odocoileus virginianus) with global positioning system collars. We found that females moved more tortuously (D 5 1.75 6 0.035 SE) than males (D 5 1.549 6 0.025). These differences in movement were related to home-range size of females but not of males. Rainfall predicted D for females; thus, females may have been able to forage more intensively in a smaller area due to increased forage availability. Fractal D of females was greatest during the parturition period (1.468 6 0.02), likely due to restricted movements in smaller areas or increased foraging. Home-range size of males was similar in spring and rut, but D was lower during rut, indicating that deer changed movement patterns within previously established home ranges. Movement patterns were similar at path lengths related to foraging patches and home ranges, whereas movement patterns changed as path length approximated the size of habitat patches.

The number of animal populations enclosed by impermeable fences has increased, which poses issues related to the behavior of individuals and populations. Despite the increased number of fenced enclosures, there is a paucity of survival and fidelity data on white-tailed deer (Odocoileus virginianus) from fenced enclosures. Therefore, we examined marked deer recaptures and resightings over 13 years for an enclosed population of white-tailed deer in Oklahoma, USA, to estimate survival and fidelity parameters. We found that a step model was the best model of survival for both sexes. Survival of females and males was greater after hunting was suspended. Average female survival was 77% before hunting was suspended but increased to 98% after. Male survival was also greater after (99%) hunting was suspended compared to before (58%). Females exhibited greater site fidelity (84–94%) than males for all age groups except old individuals, which showed similar site fidelities for males and females. Fidelity was highest for old males (85%), followed by adult (74%), fawn (61%), and yearling males (56%). Our high-tensile electric fence allowed management goals to be achieved through increased survival while potentially maintaining genetic diversity through the exchange of limited numbers of individuals from surrounding areas. However, if the goal is to confine deer to limit disease spread or protect sensitive areas (e.g., airports) from deer encroachment, then other fence designs may be necessary, because our fence was not completely effective at controlling deer movements for these purposes.

The helicopter and net gun is a technique used to capture white-tailed deer (Odocoileus virginianus) and is useful in a variety of habitat types and at various population densities with the ability to be highly selective. During capture, deer may sustain injuries or even die as a result of capture and handling, and may also be prone to capture myopathy. Therefore, our objectives were to determine 1) type and frequency of injuries sustained during the helicopter and net-gun capture, and 2) the effects of capture on survival of radiocollared deer. We captured 3,350 white-tailed deer from 1998 to 2005 using a net gun fired from a helicopter on 5 southern Texas, USA, ranches. Additionally, we captured 51 yearling males and 49 mature (≥4 yr of age) males and fitted them with radiocollars to monitor their survival. We recorded injuries and mortalities during capture and ranked the seriousness of injuries on a scale from 0 to 4. We recorded 281 injuries (8.4%) and as a result of capture, at least 206 deer had broken antlers (6.1%), 55 were injured (1.6%), and 20 were direct mortalities (0.6%). The most common antler injury was broken antler tines and the most common body injury was broken legs. Postcapture mortality rates were low (1%) for this capture method. Based on capture-related injuries, mortalities, and postcapture survival, we found the helicopter and net gun to be a safe capture technique compared to other capture techniques, particularly when conditions are favorable.

The scale at which populations use landscapes influences ecological processes and management. We used dispersal and home-range data of 3 age groups of male white-tailed deer (Odocoileus virginianus) to determine the scale at which management will be effective. Home-range size at 5.5 years of age (182 ha ± 24.9 SE) was 56% smaller (P 10,000 ha were needed to manage >50% of original yearling males found on the property, whereas properties of 4,500 ha would maintain 50% of original middle-aged (2.5–4.5 yr of age) and mature mal...

Understanding sources of male deer mortality is a prerequisite to a successful management program, especially in Texas, USA, where white-tailed deer (Odocoileus virginianus) are the most economically important game species. South Texas, USA, is one of the few areas where males reach older age classes (≥4.5 yr), in part because of intense population management. Therefore, we obtained survival rates and causes of mortality of 48 mature male deer in south Texas, USA, over 2 years. We calculated Kaplan–Meier survival estimates during 2 study years modified for a staggered-entry design and annual survival rates for one cohort of deer from 1998 to 2004 using recapture and radiotelemetry data. We documented 21 mortalities (16 harvest and 5 nonhunting mortalities). Average annual survival of the known-aged 1998 cohort was 82% with 52% of surviving to 6.5 years of age. Survival in study year 2 (0.497 ± 0.069) was less than in study year 1 (0.781 ± 0.073; P = 0.0047), largely because males had finally reac...

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.

In southern Texas, the lack of free-standing water that results from low rainfall or poor water quality can be deleterious to wildlife. Water quality can deteriorate rapidly due to evaporation during summer in southern Texas, and high concentrations of salts in water can cause physiological distress; however, little research has addressed water quality and needs of wildlife in arid environments. Our objectives were to: 1) establish water use patterns of wildlife during summer, 2) correlate visitation rates to temperature and rainfall events, and 3) monitor water quality in earthen stock ponds and concrete troughs during summer. We recorded visits to water by 17 species of wildlife and cattle. Cattle, feral pigs (Sus scrofa), and white-tailed deer (Odocoileus virginianus) had peak watering times that differed from one another. Track surveys showed a generally negative correlation between rainfall and wildlife watering frequency. Troughs had significantly higher total dissolved solids and pH than p...

A survey of turkey vultures (Cathartes aura) in South Carolina revealed the presence of a novel haemoproteid. Haemoproteus catharti n. sp. is described from the slides developed from the blood of this vulture. The new species is a thick, halteridial form with complete margins, and is considered distinct from the other recognized haemoproteids from the diurnal raptors in shape, pigment number, parasite outline, and host-family specificity. While reviewing blood films, a series of unusual immature schizonts of Plasmodium sp. were also observed, and these are illustrated, along with another distinct haemoproteid from old slides of poor quality produced from turkey vulture blood.

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.

Although, high-tensile electric fences (HTEF) have gained in popularity as a low-cost alternative to traditional fence designs, little research has focused on the effects of HTEF on white-tailed deer (Odocoileus virginianus). Our objectives were to: determine the efficacy of a HTEF to control deer movements and evaluate its influence on deer spatial dynamics. We conducted our study on the Samuel Roberts Noble Foundation Wildlife Unit located in Oklahoma, USA. An electric 15-strand, 2.5 m high fence was erected around the study area in 1992. We captured and ear-tagged 419 deer from 1993-2005 and fitted 35 of these deer (19 females, 16 males) with GPS collars during winter 1998-2004. Eight of 35 radio-collared deer (23%) crossed through the fence a total of 15 times and returned 13 times. Most fence crossings were at or near a hole or water gap (75%; n = 21) while 21.4% (n = 6) crossed through the electric strands. Twenty four of 419 (6%) ear-tagged deer were reported dead or harvested off of the property over 13 years. We found ≥13 deer core areas and ≥29 of home ranges bordered the fence. Core area and home range sizes of males and females were larger for deer associated with the fence compared to deer not associated with the fence. The percentage of deer FK core area and home range perimeters in common with the fence was 17 and 28%, respectively. It appears deer were tolerable of the fence and willing to attempt to cross at weak locations (i.e., holes and water gaps). If fully maintained, the 15-strand HTEF would have been a safe and effective alternative to more traditional and expensive fence designs.

Wood storks (Mycteria americana) are endangered throughout their breeding range in the United States. Because of this, researchers have had little opportunity to thoroughly examine the continental wood stork population for endoparasites. The blood protozoan Haemoproteus crumenium has been identified from several populations of wood storks in North America. However, there have been no reports of wood storks being infected with species of Plasmodium or Leucocytozoon. During 2003, 42 nestling wood storks were captured at sites in Georgia and 27 free-ranging wood storks were captured at postbreeding dispersal sites in Mississippi and Louisiana. Two thin blood smears were made from each bird, and they were examined for parasites. Haemoproteus crumenium was found in 5 wood storks (7.2%), whereas Leucocytozoon sp., Plasmodium sp., and microfilariae were not observed. Mean intensity of H. crumenium was 4.4 +/- 0.7 (SE) per 2,000 erythrocytes counted. All infected wood storks were subadult or adult and were from postbreeding dispersal sites in Mississippi.

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).