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Degree of reproductive synchronization in prey is hypothesized as a predator defense strategy reducing prey risk via predator satiation or predator avoidance. Species with precocial young, especially those exposed to specialist predators, should be highly synchronous to satiate predators (predator satiation hypothesis), while prey with nonprecocial (i.e. altricial) young, especially those exposed to generalist predators, should become relatively asynchronous to avoid predator detection (predator avoidance hypothesis). The white‐tailed deer Odocoileus virginianus in North America is an example of a nonprecocial ungulate that uses the hider strategy early in life; its primary predator (coyote; Canis latrans) is a generalist, making white‐tailed deer a good model species to test the predator avoidance hypothesis. We used birth dates and known fates of white‐tailed deer neonates (n = 1,032) across nine study sites varying in relative synchrony and predator assemblages to test the predator avoidance hypothesis. We predicted that relative birthing asynchrony of the population would increase relative survival at the population level; therefore, at the individual scale, neonate birth date nearer to mean birthing date in a respective population would not influence individual survival. Coyotes were responsible for the majority of predation events, and survival of those neonates increased the closer the individual was born to peak birthing season in each respective population. Also, at the population level, reproductive asynchronization negatively affected survival. Contrary to the predator avoidance hypothesis, our data indicate patterns in neonate survival for white‐tailed deer better support the predator satiation hypothesis at the individual and population level. Additionally, coyotes may present a selective force great enough to shift reproductive synchrony such that predator satiation may become a feasible defense strategy for neonates at local spatial scales. Our results indicate that synchronizing reproduction may still be the most effective strategy to reduce individual predation risk from generalist predators, particularly when the window of heightened resource availability to the prey is narrow. A free Plain Language Summary can be found within the Supporting Information of this article.

The relationship between body size and latitude has been the focus of dozens of studies across many species. However, results of testing Bergmann’s rule — that organisms in colder climates or at higher latitudes possess larger body sizes — have been inconsistent across studies. We investigated whether snowshoe hares (Lepus americanus Erxleben, 1777) follow Bergmann’s rule by investigating differences in body mass using data from six published studies and from data of 755 individual hares captured from 10 populations across North America covering 26° of north latitude. We also explored alternative hypotheses related to variation in hare body mass, including winter severity, length of growing season, elevation, and snow depth. We found body mass of hares varied throughout their range, but the drivers of body mass differed based on geographic location. In northern populations, females followed Bergmann’s rule, whereas males did not. In northern populations, male mass was related to mean snow depth. In contrast, in southern populations, body mass of both sexes was related to length of the growing season. These differences likely represent variation in the drivers of selection. Specifically, in the north, a large body size is beneficial to conserve heat because of low winter temperatures, whereas in the south, it is likely due to increased food supply associated with longer growing seasons.

Nutrition is fundamental to white-tailed deer (Odocoileus virginianus) management given its relationship to habitat carrying capacity and population productivity. Ecological Sites (ESs) are a United States federal landscape management unit of specific land potential due to unique soils, topography, climate, parent material, and perhaps deer forage nutritional value. We present results of a study that extends the use of ESs to inform white-tailed deer management by evaluating indicator plant chemistry in two spring forb species, Indian cucumber root (Medeola virginiana) and Canada mayflower (Maianthemum canadense), across the northcentral Appalachians. We sampled spring forbs and underlying soils across two ESs: Dry, upland, oak-maple-hemlock hardwood forest (OMH) and Deep soil, high slope, northern hardwood forests (NHF). Plant elemental content, soil pH, and site aspect, slope and elevation were measured. Our results show that forb chemistry differs between species and within a species geographically. Indian cucumber root, as compared to Canada mayflower, has significantly higher Mg, Na, Cu, Fe, and Zn, and lower Mn. Canada mayflower in the NHF ES, versus OMH ES, was found to have significantly higher K, Mn, and B. Indian cucumber root in the NHF ES, versus the OMH ES, was found to have significantly higher Mg, Al, Fe, and Ca:P ratio but lower K. Linear discriminant analysis shows that plant tissue Mn was the best discriminator between species, and between ESs, Canada mayflower plant tissue Mn and Indian cucumber plant tissue P, K, Ca, Mg and Mn were best discriminators. Given that nutrition determines habitat carrying capacity, differences in forage nutrition between ESs may have different potentials to support deer. Forage nutrition is an important aspect of deer habitat conditions and carrying capacity, thus ESs are likely to support deer populations with different growth potential, which means that even if the same plant species occur in different ESs their nutritional value to deer may differ.

Background Identifying the behavioral state for wild animals that can’t be directly observed is of growing interest to the ecological community. Advances in telemetry technology and statistical methodologies allow researchers to use space-use and movement metrics to infer the underlying, latent, behavioral state of an animal without direct observations. For example, researchers studying ungulate ecology have started using these methods to quantify behaviors related to mating strategies. However, little work has been done to determine if assumed behaviors inferred from movement and space-use patterns correspond to actual behaviors of individuals. Methods Using a dataset with male and female white-tailed deer location data, we evaluated the ability of these two methods to correctly identify male-female interaction events (MFIEs). We identified MFIEs using the proximity of their locations in space as indicators of when mating could have occurred. We then tested the ability of utilization distributions (UDs) and hidden Markov models (HMMs) rendered with single sex location data to identify these events. Results For white-tailed deer, male and female space-use and movement behavior did not vary consistently when with a potential mate. There was no evidence that a probability contour threshold based on UD volume applied to an individual’s UD could be used to identify MFIEs. Additionally, HMMs were unable to identify MFIEs, as single MFIEs were often split across multiple states and the primary state of each MFIE was not consistent across events. Conclusions Caution is warranted when interpreting behavioral insights rendered from statistical models applied to location data, particularly when there is no form of validation data. For these models to detect latent behaviors, the individual needs to exhibit a consistently different type of space-use and movement when engaged in the behavior. Unvalidated assumptions about that relationship may lead to incorrect inference about mating strategies or other behaviors.

Among felids worldwide, only 6 of 38 species have stable or increasing populations, and most felid species are threatened by anthropogenic influences, especially habitat loss and fragmentation. We documented changes in genetic diversity in an isolated, reintroduced population of bobcats on Cumberland Island (CUIS), Georgia, USA, compared to another bobcat population on Kiawah Island, South Carolina, USA, that was naturally established and experiences limited immigration from the mainland. The CUIS population declined from 32 reintroduced bobcats in 1989 to 10–24 individuals during 2012–2019, and observed heterozygosity declined from 0.742 to 0.634 (SD = 0.240). Observed heterozygosity of bobcats on Kiawah was 0.699 (SD = 0.153). We estimated that one bobcat immigrated to Kiawah Island every 5.3 years. We compared the predictions of a novel population viability analysis ( PVA ) to empirical estimates of abundance and genetic diversity on CUIS and used our PVA to identify management actions that are likely to support long-term viability. Mean heterozygosity from the PVA (0.588, SD = 0.065) was within 1 standard deviation of the empirical estimate. The PVA estimated the population would decline following population restoration due to loss of genetic diversity and inbreeding depression. Translocations of one female every four years would stabilize allele heterozygosity similar to the Kiawah Island population, but even translocations of two females every two years would not restore heterozygosity to founder levels. The PVA predicted no management action would result in a one in five probability of extinction within 50 years of reintroduction, but all translocation strategies nearly eliminated extinction risk through 100 years.

Abrupt changes in a forest ecosystem, whether natural or anthropogenic, are changes that occur over short time periods; such disturbance has the potential to drive state changes and alter forest resilience. Understanding how present-day abrupt forest change may alter ecosystem services is becoming more important due to ever-growing anthropogenic stresses. Forest managers trying the adapt to anthropogenic stress can benefit from the study and quantification of past abrupt changes in forests, especially when the legacy of past disturbance is still evident. Across the United Kingdom, Europe, and recently the northeastern United States, the examination of historic forest change due to charcoal manufacturing for the firing of iron or lime furnaces is yielding new insights relative to landscape stability, anthropogenic vs natural soil genesis, and forest evolution. We present results of a study that strives to evaluate how historic land clearing for the charcoal industry (supporting iron furnaces) affected local soils and may drive surrounding present day forest composition. We incorporate field sampling of hearth soils and modeled hydrologic parameters (in hearth and non-hearth areas), to quantify the uniqueness of relict charcoal hearth (RCH) systems. We identified 1,239 hearths using a LiDAR terrain analysis; approximately 10% of these were visited to quantify hearth morphology and soil moisture differences on and off hearth. Nine hearths from this 10% were intensively sampled and were associated with a northern Appalachian, USA furnace that was in operation from 1867 to 1904. Three profiles were excavated across each hearth and compared to an adjacent soil profile on the same contour. Soil descriptions were made of hearths and soil samples analyzed for total, trace and rare earth element content (Aqua Regia digestion). Soil pH (water) and fertility (Mehlich III extraction) were also determined. Results indicate that hearths have a unique geochemistry with higher bases and some concentrated metals and higher organic carbon. Coupled with a higher hearth soil water content, hypothesized to be due to an observed restrictive subsurface morphology and higher organic carbon, hearths are potentially unique locations of refugia for forest flora and fauna. Future research should more closely investigate whether hearths support unique species assemblages and how they may play a role in enhancing today’s forest biodiversity.

Throughout the northeastern United States and Europe, relic charcoal hearths (RCHs) are more regularly being discovered in proximity to furnaces used for iron or quick-lime production; charcoal was used as a primary fuel source in the furnaces. RCHs have been found across parts of Europe and Connecticut, USA in different hillslope positions, on vary degrees of slope and aspect, all of which can be a factor affecting the shape of the RCH. Their usage for charcoal production varied with the time period, furnaces were in operation with some hearths being used once and older ones (such as in Europe) being used multiple times. RCHs across the northcentral Appalachians, USA have been minimally investigated, thus determining where they occur on the landscape, their shape, and their morphologic positions will be useful in discerning their effect on surface hydrology and soil development. Our study focuses on developing a repeatable process for: finding RCHs and quantifying how RCHs may alter surface hydrology. We used a combination of processed LiDAR data to create hillshades, and slope gradients to visualize RCHs. A total of 6,758 hearths have been digitized across three study areas that reflect different historical time periods of construction and environments. We hypothesize that the construction of RCHs can alter the surface hydrology of their surrounding environments. To fully quantify the landscape-level effects of RCHs, a subset of the total was created to fully digitize the RCHs’ area. The RCH was broken into their rim and platform components. A topographic wetness index (TWI), and SAGA wetness index (SWI) was created for two study areas in order to quantify surface hydrology effects. We found that RCH platforms have a significantly higher TWI and SWI than the rim counterparts indicating that the platform is wetter than the RCH outer rims. Geomorphic position was found to not effect wetness. Using field measured volumetric water content, we found that as distance from the center of the hearth increases, the drier the soil becomes. Using a combination of GIS flow path analysis, and RCH geometry, standardized ellipses using the axis of local RCHs and the mean area of the total RCHs were created to understand the upslope (control) and downslope (experiment) effects of hearths on the surface hydrology. Preliminary analysis indicates that downslope positions from RCHs are drier than upslope positions and that there is a significant difference in the relationship between slope position and distance from an RCH and the corresponding TWI and SWI values. Future research will address the effect of slope position and distance to quantify the effect of RHCs on surface hydrology. Furthermore, the soil chemical changes from RCH creation and the increase moisture may increase the habitat for rare species of both plants and animals that otherwise would not be present. Understanding the extent of the impact human activity can have on various ecosystems can help forest managers, conservationists, pedologists, and climatologists better adapt their management or research pursuits within a specific environment to prepare for future changes, natural or anthropogenic.

It is unknown how ungulate physiological responses to environmental perturbation influence overall population demographics. Moreover, neonatal physiological responses remain poorly studied despite the importance of neonatal survival to population growth. Glucocorticoid (GC) hormones potentially facilitate critical physiological and behavioral responses to environmental perturbations. However, elevated GC concentrations over time may compromise body condition and indirectly reduce survival. We evaluated baseline salivary cortisol (CORT; a primary GC in mammals) concentrations in 19 wild neonatal white-tailed deer (Odocoileus virginianus) in a northern (NS) and southern (SS) area in Pennsylvania. After ranking survival models consisting of variables hypothesized to influence neonate survival (i.e. weight, sex), the probability of neonate survival was best explained by CORT concentrations, where elevated CORT concentrations were associated with reduced survival probability to 12 weeks of age. Cortisol concentrations were greater in the SS where predation rates and predator densities were lower. As the first evaluation of baseline CORT concentrations in an ungulate neonate to our knowledge, this is also the first study to demonstrate CORT concentrations are negatively associated with ungulate survival at any life stage. Glucocorticoid hormones could provide a framework in which to better understand susceptibility to mortality in neonatal white-tailed deer.

Perceived predation risk and the resulting antipredator behaviour varies across space, time and predator identity. Communities with multiple predators that interact and differ in their use of space, time of activity and hunting mode create a complex landscape for prey to avoid predation. Anthropogenic presence and disturbance have the potential to shift interactions among predators and prey and the where and when encounters occur. We examined how white-tailed deer Odocoileus virginianus fawn spatiotemporal antipredator behaviour differed along an anthropogenic disturbance gradient that had black bears Ursus americanus, coyotes Canis latrans, bobcats Lynx rufus and humans present. We quantified (a) spatial co-occurrence in species distributions, (b) temporal overlap across the diel cycle and (c) spatiotemporal associations between humans, bears, coyotes, bobcats, adult male deer and fawns. We also examined how deer vigilance behaviour changed across the anthropogenic disturbance gradient and survey duration. Anthropogenic disturbance influenced spatiotemporal co-occurrence across multiple scales, often increasing spatiotemporal overlap among species. In general, species' spatial co-occurrence was neutral or positive in anthropogenically disturbed environments. Bears and fawns, coyotes and adult male deer, and bobcats and fawns all had higher temporal overlap in the agriculture-development matrix sites. In addition, factors that influenced deer vigilance (e.g. distance to forest edge and predator relative abundance) in the agriculture-development matrix sites did not in the forest matrix site. By taking into account the different antipredator behaviours that can be detected and the different scales these behaviours might occur, we were able to gain a more comprehensive picture of how humans reduce available niche space for wildlife, creating the neutral and positive spatiotemporal associations between species that studies have been seeing in more disturbed areas.

In the northeastern United States, chronic wasting disease has recently been detected in white-tailed deer (Odocoileus virginianus) populations, and understanding the relationship between landscape configuration and home range may improve disease surveillance and containment efforts. The objectives of our study were to compare size of home range for deer occupying a continuum of forested landscapes and to investigate relationships between size of home range and measures of landscape configuration. We used a movement-based kernel density estimator to estimate home range at five spatial scales among deer across study areas. We developed 7 linear regression models that used measures of the configuration of the forested landscape to explain size of home range. We observed differences in size of home range between sexes among areas that differed based on landscape configuration. We documented size of home range changed with various metrics that identifying connectivity of forested patches. Generally, size of home range increased with an increasing proportion of homogenous forest. Our results suggest that deer in our region occupy a landscape at hierarchically-nested scales that is controlled by the connectivity of the forested landscape across local or broad geographical regions.

Understanding adaptations of nonhibernating northern endotherms to cope with extreme cold is important because climate-induced changes in winter temperatures and snow cover are predicted to impact these species the most. We compared winter pelage characteristics and heat production of snowshoe hares (Lepus americanus Erxleben, 1777) on the southern edge of their range, in Pennsylvania (USA), to a northern population, in the Yukon (Canada), to investigate how hares might respond to changing environmental conditions. We also investigated how hares in Pennsylvania altered movement rates and resting spot selection to cope with variable winter temperatures. Hares from Pennsylvania had shorter, less dense, and less white winter coats than their northern counterparts, suggesting lower coat insulation. Hares in the southern population had lower pelage temperatures, indicating that they produced less heat than those in the northern population. In addition, hares in Pennsylvania did not select for resting spots that offered thermal advantages, but selected locations offering visual obstruction from predators. Movement rates were associated with ambient temperature, with the smallest movements occurring at the lower and upper range of observed ambient temperatures. Our results indicate that snowshoe hares may be able to adapt to future climate conditions via changes in pelage characteristics, metabolism, and behavior.

We present a case study from New York, USA, of the use of structured decision making (SDM) to identify fall turkey harvest regulations that best meet stakeholder objectives, in light of recent apparent declines in abundance of wild turkeys in the northeastern United States. We used the SDM framework to incorporate the multiple objectives associated with turkey hunting, stakeholder desires, and region-specific ecological and environmental factors that could influence fall harvest. We identified a set of 4 fall harvest regulations, composed of different season lengths and bag limits, and evaluated their relative achievement of the objectives. We used a stochastic turkey population model, statistical modeling, and expert elicitation to evaluate the consequences of each harvest regulation on each of the objectives. We conducted a statewide mail survey of fall turkey hunters in New York to gather the necessary information to evaluate tradeoffs among multiple objectives associated with hunter satisfaction. The optimal fall harvest regulation was a 2-week season and allowed for the harvest of 1 bird/hunter. This regulation was the most conservative of those evaluated, reflecting the concerns about recent declines in turkey abundance among agency wildlife biologists and the hunting public. Depending on the region of the state, the 2-week, 1-bird regulation was predicted to result in 7–32% more turkeys on the landscape after 5 years. The SDM process provided a transparent framework for setting fall turkey harvest regulations and reduced potential stakeholder conflict by explicitly taking the multiple objectives of different stakeholder groups into account. © 2017 The Wildlife Society.

Selective harvest criteria, such as antler point restrictions (APRs), have been used to regulate harvest of male ungulates; however, comprehensive evaluation of the biological and social responses to this management strategy is lacking. In 2002, Pennsylvania adopted new APRs for white-tailed deer (Odocoileus virginianus) that required, depending on wildlife management unit, ≥3 or ≥4 points on 1 antler for legal harvest. Historically, harvest rates of subadult (1.5 yr old) and adult (≥2.5 yr old) antlered males averaged 0.80. Antler point restrictions were designed to protect ≥50% of subadult males from harvest. Most adult males remained legal for harvest. We estimated harvest rates, survival rates, and cause-specific mortality of radio-collared male deer (453 subadults, 103 adults) in 2 wildlife management units (Armstrong and Centre counties) to evaluate biological efficacy of APRs to increase recruitment of adult males during 2002–2005. We administered statewide deer hunter surveys before and after each hunting season over the same 3 years to evaluate hunter attitudes toward APRs. We conducted 2 types of surveys: a simple random sample of all license buyers for each survey and a longitudinal panel of hunters who completed all 6 surveys. At the same time APRs were implemented, the Pennsylvania Game Commission (PGC) increased antlerless harvests to reduce deer density to meet deer management goals. Survival rates varied by month and age but not between study areas or among years after implementation of APRs. Monthly survival rates for subadults ranged from 0.64 to 0.97 during hunting seasons and 0.95 to 0.99 during the non-hunting period. Annual survival of subadults was 0.46 (95% CI = 0.41–0.52). Adult monthly survival rates ranged from 0.36 to 0.95 during hunting seasons and we had no mortalities during the non-hunting period. Annual survival of adults was 0.28 (95% CI = 0.22–0.35). Antler point restrictions successfully reduced harvest rate for subadults to 0.31 (95% CI = 0.23–0.38), and approximately 92% of these deer survived to the following hunting season. Vehicle collisions were the greatest source of mortality outside the hunting season for subadults and adults. Also, we observed decreased harvest rates for adults (0.59, 95% CI = 0.40–0.72), although nearly all were legal for harvest. Of radio-collared subadults, 6–11% were harvested with sub-legal antlers, indicating hunters generally complied with APRs. Overall, antlered harvest declined statewide and in our study areas, in part because of APRs but also because of increased antlerless harvests that reduced the statewide population from 1.49 million deer in 2000 to 1.14 million deer in 2005. However, between 2000 and 2005, harvest of adult males increased by 976 (112%) in Armstrong County, decreased by 29 (−3%) in Centre County, and increased by 14,285 (29%) statewide because more males survived to the 3- and 4-year-old age classes. Proportion of hunters from the random sample surveys who supported statewide APRs varied among years between 0.61 (95% CI = 0.59–0.64) and 0.70 (95% CI = 0.66–0.73). The proportion of hunters from the longitudinal panel who supported APRs did not increase as hunters gained experience under the new regulations; 0.23 were more supportive, 0.29 were less supportive, and 0.48 were unchanged in their level of agreement after 3 years. Although >50% of hunters supported APRs throughout the study, support for the PGC's deer management program declined; 41% of the longitudinal panel of hunters rated the deer management program lower after 3 years and 21% rated it higher. We considered APRs biologically successful because of decreased subadult harvest rates and increased harvest of adult males with larger antlers. Likewise, because the majority of hunters supported APRs throughout the study, we considered APRs socially successful. However, we predicted APRs would become increasingly popular after hunters experienced biological results of APRs, but there was little change in support. We believe hunters formed an initial impression of the effects of APRs, and additional experience and information failed to change their opinion. Furthermore, the concurrent reduction in overall deer densities to accommodate more males in the population and to meet agency deer population goals likely further reduced support for APRs. We found APRs as implemented in Pennsylvania to be enforceable, adhered to by hunters, and successful in recruiting more antlered males to older age classes. To facilitate social acceptance of these regulation changes, we found that obtaining support before the changes were implemented may have been important because most hunters did not change their opinions about APRs after 3 years of experience with the new regulations. © 2017 The Wildlife Society.

Understanding the geographic extent and connectivity of wildlife populations can provide important insights into the management of disease outbreaks but defining patterns of population structure is difficult for widely distributed species. Landscape genetic analyses are powerful methods for identifying cryptic structure and movement patterns that may be associated with spatial epizootic patterns in such cases.We characterized patterns of population substructure and connectivity using microsatellite genotypes from 2,222 white‐tailed deer (Odocoileus virginianus) in the Mid‐Atlantic region of the United States, a region where chronic wasting disease was first detected in 2009. The goal of this study was to evaluate the juxtaposition between population structure, landscape features that influence gene flow, and current disease management units.Clustering analyses identified four to five subpopulations in this region, the edges of which corresponded to ecophysiographic provinces. Subpopulations were further partitioned into 11 clusters with subtle (F ST ≤ 0.041), but significant genetic differentiation. Genetic differentiation was lower and migration rates were higher among neighboring genetic clusters, indicating an underlying genetic cline. Genetic discontinuities were associated with topographic barriers, however.Resistance surface modeling indicated that gene flow was diffuse in homogenous landscapes, but the direction and extent of gene flow were influenced by forest cover, traffic volume, and elevational relief in subregions heterogeneous for these landscape features. Chronic wasting disease primarily occurred among genetic clusters within a single subpopulation and along corridors of high landscape connectivity.These results may suggest a possible correlation between population substructure, landscape connectivity, and the occurrence of diseases for widespread species. Considering these factors may be useful in delineating effective management units, although only the largest features produced appreciable differences in subpopulation structure. Disease mitigation strategies implemented at the scale of ecophysiographic provinces are likely to be more effective than those implemented at finer scales., We characterized the spatial population structure of white‐tailed deer in the Mid‐Atlantic region of the United States in order to evaluate the juxtaposition population structure, gene flow patterns, and chronic wasting disease cases in the region. We found evidence of four to five subpopulation units, the extents of which generally corresponded with ecophysiographic provinces, with 11 subtle genetic clusters nested hierarchically within subpopulation units. Landscape genetic analyses revealed corridors of high connectivity adjacent to ridges, roads, and open areas, which may indicate directed disease transmission in regions heterogeneous for these features.

Localized management of white-tailed deer (Odocoileus virginianus) involves the removal of matriarchal family units with the intent to create areas of reduced deer density. However, application of this approach has not always been successful, possibly because of female dispersal and high deer densities. We developed a spatially explicit, agent-based model to investigate the intensity of deer removal required to locally reduce deer density depending on the surrounding deer density, dispersal behavior, and size and shape of the area of localized reduction. Application of this model is illustrated using the example of abundant deer populations in Pennsylvania, USA. Most scenarios required at least 5 years before substantial deer density reductions occurred. Our model indicated that a localized reduction was successful for scenarios in which the surrounding deer density was lowest (30 deer/mi²), localized antlerless harvest rates were ≥ 30%, and the removal area was ≥ 5 mi² . When the size of the removal area was

Ultimate causes of animal dispersal have been hypothesized to benefit the dispersing individual because dispersal reduces competition for local resources, potential for inbreeding, and competition for breeding partners. However, proximate cues influence important features of dispersal behavior, including when dispersal occurs, how long it lasts, and direction, straightness, and distance of the dispersal path. Therefore, proximate cues that affect dispersal influence ecological processes (e.g., population dynamics, disease transmission, gene flow). We captured and radio-marked 277 juvenile female white-tailed deer (Odocoileus virginianus), of which 27 dispersed, to evaluate dispersal behavior and to determine proximate cues that may influence dispersal behavior. Female dispersal largely occurred at 1 year of age and coincided with the fawning season. Dispersal paths varied but generally were non-linear and prolonged. Physical landscape features (i.e., roadways, rivers, residential areas) influenced dispersal path direction and where dispersal terminated. Additionally, forays outside of the natal range that did not result in dispersal occurred among 52% of global positioning system (GPS)-collared deer (n = 25) during the dispersal period. Our results suggest intra-specific social interactions and physical landscape features influence dispersal behavior in female deer. Female dispersal behavior, particularly the lack of directionality, the semi-permeable nature of physical barriers, and the frequency of forays outside of the natal range, should be considered in regard to population management and controlling the spread of disease. © 2016 The Wildlife Society.

In Pennsylvania, Lepus americanus (Snowshoe Hare) is near the southern limits of its range and at risk of range contraction because of loss of early-successional forest and impacts of climate change. We used hunter-harvest data to investigate changes in the distribution of Snowshoe Hare in Pennsylvania (1983–2011), forest inventory and land-use data to assess changes in amount and distribution of early-successional forest (1988–2011), and occupancy modeling (2004) to identify habitat and climate variables that explain the current distribution of Snowshoe Hare. We determined presence of Snowshoe Hare based on visual sightings, observations of tracks, and DNA analysis of fecal pellets, and used repeated visits to sampling sites and occupancy models to estimate occupancy rates (Ψ). Hunter-harvest data indicated the range of Snowshoe Hare in Pennsylvania contracted towards northwestern and northeastern portions of the state. Based on occupancy modeling, Snowshoe Hare were most likely to occupy early-...

The loss of species diversity and plant community structure throughout the temperate deciduous forests of North America have often been attributed to overbrowsing by white-tailed deer (Odocoileus virginanus). Slow species recovery following removal from browsing, or reduction in deer density, has been termed a legacy effect of past deer herbivory. However, vegetation legacy effects have also coincided with changes to soil chemistry throughout the north-eastern USA. In this paper, we assess the viability of soil chemistry (i.e. pH, extractable nutrients and extractable metals) and other factors (topography, light, overstory basal area and location) as alternative explanations for a lack of vegetation recovery. We compared the relative effects of soil chemistry, site conditions and short-term (1–2 year) deer exclusion on single-species occupancy probabilities of 10 plant taxa common to oak-hickory forests in central Pennsylvania. We found detection for all modelled species was constant and high (p^ > 0.65), and occupancy probability of most taxa was best explained by at least one soil chemistry parameter. Specifically, ericaceous competing vegetation was more likely to occupy acidic (pH < 3.5), base cation-poor (K < 0.20 cmolc kg−1) sites, while deer-preferred plants were less likely to occur when soil manganese exceeded 0.1 cmolc kg−1. Short-term deer exclusion did not explain occupancy of any plant taxon, and site conditions were of nominal importance. This study demonstrates the importance of soil chemistry in shaping plant community composition in the north-central Appalachians, and suggests soil as an alternative, or additional, explanation for deer vegetation legacy effects. We suggest that the reliance on phyto-indicators of deer browsing effects may overestimate the effects of browsing if those species are also limited by unfavourable soil conditions. Future research should consider study designs that address the complexity of deer forest interactions, especially in areas with complex site-vegetation histories.

Made available in DSpace on 2018-11-26T17:44:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-01-26 Robert Bosch Foundation Animal movement is fundamental for ecosystem functioning and species survival, yet the effects of the anthropogenic footprint on animal movements have not been estimated across species. Using a unique GPS-tracking database of 803 individuals across 57 species, we found that movements of mammals in areas with a comparatively high human footprint were on average one-half to one-third the extent of their movements in areas with a low human footprint. We attribute this reduction to behavioral changes of individual animals and to the exclusion of species with long-range movements from areas with higher human impact. Global loss of vagility alters a key ecological trait of animals that affects not only population persistence but also ecosystem processes such as predator-prey interactions, nutrient cycling, and disease transmission. 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Fitotecn, P-7002554 Evora, Portugal Univ Evora, ICAAM, Inst Mediterranean Agr & Environm Sci, Evora, Portugal Univ Montpellier, Univ Paul Valery Montpellier, CNRS,EPHE, Ctr Ecol Fonctionnelle & Evolut,UMR 5175, F-34293 Montpellier 5, France Phillip Isl Nat Parks, Cowes, Vic, Australia Monash Univ, Sch Biol Sci, Melbourne, Vic, Australia Ohio State Univ, Dept Civil Environm & Geodet Engn, Columbus, OH 43210 USA Fiji Natl Univ, Dept Biol, POB 5529, Natabua, Lautoka, Fiji Univ Massachusetts, US Geol Survey, Massachusetts Cooperat Fish & Wildlife Res Unit, Amherst, MA 01003 USA Penn State Univ, US Geol Survey, Penn Cooperat Fish & Wildlife Res Unit, University Pk, PA 16802 USA Univ Oxford, Dept Zool, Oxford OX1 3PS, England Giraffe Conservat Fdn, POB 86099, Eros, Namibia German Primate Ctr, Behav Ecol & Sociobiol Unit, D-37077 Gottingen, Germany Tech Univ Munich, Dept Ecol & Ecosyst Management, Restorat Ecol, D-85354 Freising Weihenstephan, Germany Cary Inst Ecosyst Studies, Millbrook, NY 12545 USA Univ British Columbia, Irving K Barber Sch Arts & Sci, Unit 2, Biol, Okanagan Campus, Kelowna, BC V1V 1V7, Canada Univ Zurich, Dept Evolutionary Biol & Environm Studies, CH-8057 Zurich, Switzerland Univ Wyoming, Dept Zool & Physiol, Laramie, WY 82071 USA Univ Washington, Sch Environm & Forest Sci, Seattle, WA 98195 USA Univ Montana, Coll Forestry & Conservat, Dept Ecosyst & Conservat Sci, Wildlife Biol Program, Missoula, MT 59812 USA Bavarian Forest Natl Pk, Dept Conservat & Res, D-94481 Grafenau, Germany Albert Ludwigs Univ Freiburg, Wildlife Ecol & Management, D-79106 Freiburg, Germany Univ Toulouse, INRA, CEFS, Castanet Tolosan, France Univ Calif Davis, Anim Behav Grad Grp, Davis, CA 95616 USA Bionet Natr Onderzoek, NL-6171 EL Stein, Netherlands Univ Vet Med Vienna, Res Inst Wildlife Ecol, A-1160 Vienna, Austria Univ Coll Cork, Sch Biol Earth & Environm Sci, Cork, Ireland Univ Wyoming, US Geol Survey, Dept Zool & Physiol, Wyoming Cooperat Fish & Wildlife Res Unit, Laramie, WY USA North Carolina Museum Nat Sci, Raleigh, NC 27601 USA North Carolina State Univ, Dept Forestry & Environm Resources, Raleigh, NC 27695 USA Karatina Univ, Dept Nat Resource Management, POB 195710101, Karatina, Kenya Univ Lethbridge, Dept Psychol, Lethbridge, AB T1K 3M4, Canada Columbia Univ, Lamont Doherty Earth Observ, Palisades, NY 10964 USA Univ Valencia, Terr Vertebrates Grp, Cavanilles Inst Biodivers & Evolutionary Biol, E-46980 Valencia, Spain SUNY Stony Brook, Dept Anthropol, Stony Brook, NY 11794 USA TSG, SSC, IUCN, Rua Licuala 622,Damha 1,Campo Grande, BR-79046150 Mato Grosso Sul, Brazil IPE Inst Pesquisas Ecol Inst Ecol Res, Caixa Postal 47, BR-12960000 Sao Paulo, Brazil Univ Alicante, Dept Ciencias Ambient & Recursos Natur, Vertebrates Zool Res Grp, Alicante, Spain Embrapa Pantanal, BR-79320900 Corumba, MS, Brazil Chico Mendes Inst Conservat Biodivers, Natl Res Ctr Carnivores Conservat, BR-12952011 Atiba, SP, Brazil Univ Glasgow, Inst Biodivers Anim Hlth & Comparat Med, Glasgow, Lanark, Scotland NYU, Dept Biol, Ctr Genom & Syst Biol, New York, NY 10003 USA Univ Calif Davis, Dept Microbiol & Mol Genet, Davis, CA 95616 USA Univ Oslo, Dept Biosci, Ctr Ecol & Evolutionary Synth, NO-0316 Oslo, Norway Hebrew Univ Jerusalem, Alexander Silberman Inst Life Sci, Dept Ecol Evolut & Behav, Movement Ecol Lab, IL-91904 Jerusalem, Israel Norwegian Inst Nat Res, NO-0349 Oslo, Norway Norwegian Univ Sci & Technol NTNU, Dept Math Sci & Ctr Biodivers Dynam, N-7491 Trondheim, Norway Univ Fed Mato Grosso do Sul, Dept Ecol, BR-79070900 Campo Grande, MS, Brazil Field Museum Nat Hist, Integrat Res Ctr, Chicago, IL 60605 USA Consorzio Parco Nazl Stelvio, Bormio, Sondrio, Italy Univ Grenoble Alpes, Irstea, UR LESSEM, BP 76, F-38402 St Martin Dheres, France Univ Bayreuth, BayCEER, D-95447 Bayreuth, Germany Natl Park Schwarzwald, D-77889 Seebach, Germany Univ New South Wales, Evolut & Ecol Res Ctr, Sydney, NSW 2052, Australia Univ New South Wales, Sch Biol Earth & Environm Sci, Sydney, NSW 2052, Australia Penn Game Commiss, Harrisburg, PA 17110 USA Princeton Univ, Dept Ecol & Evolutionary Biol, Princeton, NJ 08544 USA Univ Konstanz, Dept Biol, D-78467 Constance, Germany Off Natl Chasse & Faune Sauvage, Studies & Expertise DRE, F-01330 Birieux, France Univ Haifa, Dept Evolutionary & Environm Biol, IL-3498838 Haifa, Israel Western Ecosyst Technol Inc, Laramie, WY 82070 USA Aarhus Univ, Arctic Res Ctr, DK-8000 Aarhus C, Denmark Polish Acad Sci, Inst Nat Conservat, PL-31120 Krakow, Poland Univ Porto, CIBIO InBIO Associate Lab, P-4485661 Vairao, Portugal Univ Lisbon, Inst Super Agron, InBIO Associate Lab, Ctr Appl Ecol Prof Baeta Neves, P-1349017 Lisbon, Portugal Univ Lisbon, Fac Ciencias, Ctr Ecol Evolut & Environm Changes, P-1749016 Lisbon, Portugal Univ Calif Davis, Dept Environm Sci & Policy, Davis, CA 95616 USA Jackson Hole Conservat, Jackson, WY 83001 USA Univ Vet Med Hannover, Inst Terr & Aquat Wildlife Res, D-30173 Hannover, Germany Univ Calif Santa Cruz, Environm Studies Dept, Ctr Integrated Spatial Res, Santa Cruz, CA 95060 USA Univ Pretoria, Dept Zool & Entomol, ZA-0028 Hatfield, South Africa Colorado State Univ, Dept Fish Wildlife & Conservat Biol, Ft Collins, CO 80523 USA Tatra Natl Pk, PL-34500 Zakopane, Poland Sao Paulo State Univ, Anim Biol Postgra Program, BR-15054000 Sao Jose Do Rio Preto, SP, Brazil

Dispersal behavior in white-tailed deer (Odocoileus virginianus) predominantly occurs in 1-year-old males; however, females of the same age also disperse. The timing of female dispersal during fawning season and low dispersal rates suggest that competition for mates and reduced inbreeding are not ultimate causes of female dispersal, as suggested for males. We proposed that female dispersal is the result of competition for space when pregnant females seek to isolate themselves before and after parturition. To test this hypothesis, we conducted a meta-analysis of female dispersal rates from 12 populations of white-tailed deer and predicted dispersal rate and distance were positively related to deer density. We found a positive relationship between dispersal rate and deer per forested km 2 and between dispersal distance and deer per forested km 2 . These results are consistent with the hypothesis that female dispersal is density-dependent and caused by the exclusion of subordinate 1-year-olds as adult females seek isolation before and after parturition.

Mark-recapture estimators assume no loss of marks to provide unbiased estimates of population parameters. We describe a hidden Markov model (HMM) framework that integrates a mark loss model with a Cormack–Jolly–Seber model for survival estimation. Mark loss can be estimated with single-marked animals as long as a sub-sample of animals has a permanent mark. Double-marking provides an estimate of mark loss assuming independence but dependence can be modeled with a permanently marked sub-sample. We use a log-linear approach to include covariates for mark loss and dependence which is more flexible than existing published methods for integrated models. The HMM approach is demonstrated with a dataset of black bears (Ursus americanus) with two ear tags and a subset of which were permanently marked with tattoos. The data were analyzed with and without the tattoo. Dropping the tattoos resulted in estimates of survival that were reduced by 0.005–0.035 due to tag loss dependence that could not be modeled. We also analyzed the data with and without the tattoo using a single tag. By not using. Supplementary materials accompanying this paper appear on-line.

In order for mark–recapture models to provide unbiased estimates of population parameters, it is critical that uniquely identifying tags or marks are not lost. We double-banded male and female wild turkeys with aluminum rivet bands and estimated the probability that a bird would be recovered with both bands

Radio transmitters are a commonly used tool for monitoring the fates of harvested species, although little research has been devoted to whether a visible radio transmitter changes a hunters' willingness to harvest that animal. We initially surveyed deer hunters to assess their willingness to harvest radio-collared deer and predicted radio collars were unlikely to affect the harvest of antlerless deer, but hunters may be less willing to harvest small-antlered males with radio collars compared to large-antlered males. We fitted white-tailed deer (Odocoileus virginianus) with radio collars that were visible to hunters or with ear-tag transmitters or ear-tags that were difficult to detect visually and estimated if harvest rates differed among marking methods. For females, the best model failed to detect an effect of radio collars on harvest rates. Also, we failed to detect a difference between male deer fitted with radio collars and ear-tag transmitters. When we compared males fitted with radio collars versus ear tags, we found harvest rate patterns were opposite to our predictions, with lower harvest rates for adult males fitted with radio collars and higher harvest rates for yearling males fitted with radio collars. Our study suggests that harvest rate estimates generated from a sample of deer fitted with visible radio collars can be representative of the population of inference. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Many studies have documented that coyotes (Canis latrans) are the greatest source of natural mortality for white-tailed deer (Odocoileus virginianus) neonates (

Organisms can be affected by processes in the surrounding landscape outside the boundary of habitat areas and by local vegetation characteristics. There is substantial interest in understanding how these processes affect populations of grassland birds, which have experienced substantial population declines. Much of our knowledge regarding patterns of occupancy and density stem from prairie systems, whereas relatively little is known regarding how occurrence and abundance of grassland birds vary in reclaimed surface mine grasslands. Using distance sampling and single-season occupancy models, we investigated how the occupancy probability of Grasshopper (Ammodramus savannarum) and Henslow's Sparrows (A. henslowii) on 61 surface mine grasslands (1591 ha) in Pennsylvania changed from 2002 through 2011 in response to landscape, grassland, and local vegetation characteristics . A subset (n = 23; 784 ha) of those grasslands were surveyed in 2002, and we estimated changes in sparrow density and vegetation across 10 years. Grasshopper and Henslow's Sparrow populations declined 72% and 49%, respectively from 2002 to 2011, whereas overall woody vegetation density increased 2.6 fold. Henslow's Sparrows avoided grasslands with perimeter–area ratios ≥0.141 km/ha and woody shrub densities ≥0.04 shrubs/m2. Both species occupied grasslands ≤13 ha, but occupancy probability declined with increasing grassland perimeter–area ratio and woody shrub density. Grassland size, proximity to nearest neighboring grassland ( = 0.2 km), and surrounding landscape composition at 0.5, 1.5, and 3.0 km were not parsimonious predictors of occupancy probability for either species. Our results suggest that reclaimed surface mine grasslands, without management intervention, are ephemeral habitats for Grasshopper and Henslow's Sparrows. Given the forecasted decline in surface coal production for Pennsylvania, it is likely that both species will continue to decline in our study region for the foreseeable future. Patrones de Ocupacion de Poblaciones Regionalmente Declinantes de Gorriones de Pastizales en un Paisaje Boscoso de Pennsylvania Resumen Los organismos pueden ser afectados por procesos en el paisaje que los rodea por fuera de los limites de las areas de habitat y por las caracteristicas de la vegetacion local. Hay un interes sustancial en entender como estos procesos afectan a las poblaciones de aves de pastizales, las cuales han experimentado declinaciones sustanciales en la poblacion. Mucho de nuestro conocimiento con respecto a los patrones de ocupacion y a la densidad parten de sistemas de praderas, mientras que relativamente se sabe poco con respecto a como la ocurrencia y la abundancia de las aves de pastizales varia en pastizales de minas de superficiales reclamadas. Usando muestreo a distancia y modelos de ocupacion de una sola temporada, investigamos como la probabilidad de ocupacion de los gorriones Ammodramus savannarum y A. henslowii en 61 pastizales de minas superficiales (1591 ha) en Pennsylvania, que han cambiado desde 2002 y hasta el 2011 n respuesta a las caracteristicas de paisaje, pastizales y de la vegetacion local. Un subconjuto (n = 23; 784 ha) de estos pastizales fue muestreado en 2002 y estimamos cambios en la densidad de gorriones y en la vegetacion a lo largo de 10 anos. Las poblaciones de A. savannarum y A, henslowii declinaron 72% y 49% respectivamente de 2002 a 2011, mientras que la densidad de la vegetacion lenosa en general incremento al 2.6. Los gorriones A. henslowii evitaron los pastizales con radios de area-perimetro ≥0.141 km/ha y con densidades de arbustos lenosos ≥0.04 arbustos/m2. Ambas especies ocuparon pastizales ≤ 13 ha, pero la probabilidad de ocupacion declino con el incremento en el radio area-perimetro de los pastizales y la densidad de arbustos lenosos. El tamano del pastizal, la proximidad al pastizal vecino mas cercano (= 0.2 km) y la composicion de los paisajes circundantes en 0.5 km, 1.5 km y 3.0 km no fueron indicadores parsimoniosos de la probabilidad de ocupacion para ambas especies. Nuestros resultados sugieren que los pastizales de minas superficiales reclamadas, sin intervencion del manejo, son habitats efimeros para gorriones A. savannarum y A. henslowii. Dada la declinacion predicha en la produccion de carbon superficial para Penssylvania, es probable que ambas especies continuen declinando en nuestra region de estudio en el futuro.

Summary Often less expensive and less invasive than conventional mark–recapture, so-called 'mark-resight' methods are popular in the estimation of population abundance. These methods are most often applied when a subset of the population of interest is marked (naturally or artificially), and non-invasive sighting data can be simultaneously collected for both marked and unmarked individuals. However, it can often be difficult to identify marked individuals with certainty during resighting surveys, and incomplete identification of marked individuals is potentially a major source of bias in mark-resight abundance estimators. Previously proposed solutions are ad hoc and will tend to underperform unless marked individual identification rates are relatively high (>90%) or individual sighting heterogeneity is negligible. Based on a complete data likelihood, we present an approach that properly accounts for uncertainty in marked individual detection histories when incomplete identifications occur. The models allow for individual heterogeneity in detection, sampling with (e.g. Poisson) or without (e.g. Bernoulli) replacement, and an unknown number of marked individuals. Using a custom Markov chain Monte Carlo algorithm to facilitate Bayesian inference, we demonstrate these models using two example data sets and investigate their properties via simulation experiments. We estimate abundance for grassland sparrow populations in Pennsylvania, USA when sampling was conducted with replacement and the number of marked individuals was either known or unknown. To increase marked individual identification probabilities, extensive territory mapping was used to assign incomplete identifications to individuals based on location. Despite marked individual identification probabilities as low as 67% in the absence of this territorial mapping procedure, we generally found little return (or need) for this time-consuming investment when using our proposed approach. We also estimate rookery abundance from Alaskan Steller sea lion counts when sampling was conducted without replacement, the number of marked individuals was unknown, and individual heterogeneity was suspected as non-negligible. In terms of estimator performance, our simulation experiments and examples demonstrated advantages of our proposed approach over previous methods, particularly when marked individual identification probabilities are low and individual heterogeneity levels are high. Our methodology can also reduce field effort requirements for marked individual identification, thus, allowing potential investment into additional marking events or resighting surveys.

The influence of vegetation structure on the probability of daily nest survival (DNS) for grassland passerines has received considerable attention. Some correlative studies suggest that the presence of woody vegetation lowers DNS. Over 3 years (2009–2011), we monitored 215 nests of the Grasshopper Sparrow (Ammodramus savannarum) and Henslow's Sparrow (A. henslowii) on 162 ha of reclaimed surface-mine grasslands in Pennsylvania. We removed shrubs from treatment plots with ≤36% areal coverage of woody vegetation in a before-after-control-impact-pairs (BACIP) design framework. Daily nest survival (95% CI: 0.94–0.96) was as high as previous studies have reported but was not associated with woody vegetative cover, proximity to woody vegetation, or woody stem density. Variation in DNS was best explained by increasing nonwoody-vegetation height. Grasshopper Sparrow fledgling production on treatment plots in 2010 (95% CI: 3.3–4.7) and 2011 (95% CI: 3.8–5.0) was similar to baseline conditions of treatmen...

A review of the Pennsylvania Game Commission's (PGC) deer management program and public concern about predator impacts on deer (Odocoileus virginianus) populations compelled the PGC to investigate the role of age ratios in developing management recommendations. Age ratios, such as proportion of juveniles in the antlerless harvest, may provide an index to population productivity and predator impacts. We estimated proportion of juveniles in the antlerless harvest from hunter-killed deer, population trends using the Pennsylvania (USA) sex–age–kill model, and reproduction from road-killed females. Using these estimates and a simulation model, we concluded that no single age-ratio value would serve as a reliable measure of population status. Wildlife Management Unit-specific trends in proportion of juveniles in the antlerless harvest and population trends provided the most relevant management information. We also provide an example decision chart to guide management actions in response to declining age ratios in the harvest. Although predator management activities and juvenile survival studies are often desired by the public, our decision-chart example indicated a number of deer management options exist before investing resources in predator management activities and juvenile survival studies. Published 2011. This article is a U.S. Government work and is in the public domain in the USA.

Spring harvest rates of male wild turkeys (Meleagris gallapavo) influence the number and proportion of adult males in the population and turkey population models have treated harvest as additive to other sources of mortality. Therefore, hunting regulations and their effect on spring harvest rates have direct implications for hunter satisfaction. We used tag recovery models to estimate survival rates, investigate spatial, temporal, and demographic variability in harvest rates, and assess how harvest rates may be related to management strategies and landscape characteristics. We banded 3,266 male wild turkeys throughout New York, Ohio, and Pennsylvania during 2006–2009. We found little evidence that harvest rates varied by year or management zone. The proportion of the landscape that was forested within 6.5 km of the capture location was negatively related to harvest rates; however, even though the proportion forested ranged from 0.008 to 0.96 across our study area, this corresponded to differences in harvest rates of only 2–5%. Annual survival was approximately twice as high for juveniles as adults . In turn, spring harvest rates for adult turkeys were greater for adults than juveniles . We estimated the population of male turkeys in New York and Pennsylvania ranged from 104,000 to 132,000 in all years and ranged from 63,000 to 75,000 in Ohio. Because of greater harvest rates for adult males, the proportion of adult males in the population was less than in the harvest and ranged from 0.40 to 0.81 among all states and years. The high harvest rates observed for adults may be offset by greater recruitment of juveniles into the adult age class the following year such that these states can sustain high harvest rates yet still maintain a relative high proportion of adult males in the harvest and population. © 2011 The Wildlife Society.

The performance of 2 popular methods that use age-at-harvest data to estimate abundance of white-tailed deer is contingent on assumptions about variation in estimates of subadult (1.5 yr old) and adult (≥2.5 yr old) male harvest rates. Auxiliary data (e.g., estimates of survival or harvest rates from radiocollared animals) can be used to relax some assumptions, but unless these population parameters exhibit limited temporal or spatial variation, these auxiliary data may not improve accuracy. Unfortunately maintaining sufficient sample sizes of radiocollared deer for parameter estimation in every wildlife management unit (WMU) is not feasible for most state agencies. We monitored the fates of 397 subadult and 225 adult male white-tailed deer across 4 WMUs from 2002 to 2008 using radio telemetry. We investigated spatial and temporal variation in harvest rates and investigated covariates related to the patterns observed. We found that most variation in harvest rates was explained spatially and that adult harvest rates (0.36–0.69) were more variable among study areas than subadult harvest rates (0.26–0.42). We found that hunter effort during the archery and firearms season best explained variation in harvest rates of adult males among WMUs, whereas hunter effort during only the firearms season best explained harvest rates for subadult males. From a population estimation perspective, it is advantageous that most variation was spatial and explained by a readily obtained covariate (hunter effort). However, harvest rates may vary if hunting regulations or hunter behavior change, requiring additional field studies to obtain accurate estimates of harvest rates. © 2011 The Wildlife Society.

Models of resource selection are being used increasingly to predict or model the effects of management actions rather than simply quantifying habitat selection. Multilevel, or hierarchical, models are an increasingly popular method to analyze animal resource selection because they impose a relatively weak stochastic constraint to model heterogeneity in habitat use and also account for unequal sample sizes among individuals. However, few studies have used multilevel models to model coefficients as a function of predictors that may influence habitat use at different scales or quantify differences in resource selection among groups. We used an example with white-tailed deer (Odocoileus virginianus) to illustrate how to model resource use as a function of distance to road that varies among deer by road density at the home range scale. We found that deer avoidance of roads decreased as road density increased. Also, we used multilevel models with sika deer (Cervus nippon) and white-tailed deer to exami...

Grasslands resulting from surface mine reclamation support grassland songbird populations in several midwestern and eastern states in the United States, especially where reclaimed mines are large (>1,000 ha). However, most reclaimed surface mines in Pennsylvania are small (

Long-term vegetation monitoring projects are often used to evaluate how plant communities change through time in response to some external influence. Here, we evaluate the efficacy of vegetation monitoring to consistently detect changes in white-tailed deer browsing effects. Specifically, we compared inter-rater reliability (Cohen&rsquo, s &kappa, and Lin&rsquo, s concordance correlation coefficient) between two identically trained field crews for several plant metrics used by Pennsylvania state agencies to monitor deer browsing impact. Additionally, we conducted a power analysis to determine the effect of sampling scale (1/2500th or 1/750th ha plots) on the ability to detect changes in tree seedling stem counts over time. Inter-rater reliability across sampling crews was substantial for most metrics based on direct measurements, while the observational based Deer Impact Index (DII) had only moderate inter-rater reliability. The smaller, 1/2500th ha sampling scale resulted in higher statistical power to detect changes in tree seedling stem counts due to reduced observer error. Overall, this study indicates that extensive training on plant identification, project protocols, and consistent data collection methods can result in reliable vegetation metrics useful for tracking understory responses to white-tailed deer browsing. Smaller sampling scales and objective plant measures (i.e., seedling counts, species richness) improve inter-rater reliability over subjective measures of deer impact (i.e., DII). However, considering objective plant measures when making a subjective assessment regarding deer browsing effects may also improve DII inter-rater reliability.

Overexploitation of wildlife populations occurs across the humid tropics and is a significant threat to the long-term survival of large-bodied primates. To investigate the impacts of hunting on primates and ways to mitigate them, we developed a spatially explicit, individual-based model for a landscape that included hunted and un-hunted areas. We used the large-bodied neotropical red howler monkey (Alouatta seniculus) as our case study species because its life history characteristics make it vulnerable to hunting. We modeled the influence of different rates of harvest and proportions of landscape dedicated to un-hunted reserves on population persistence, population size, social dynamics, and hunting yields of red howler monkeys. In most scenarios, the un-hunted populations maintained a constant density regardless of hunting pressure elsewhere, and allowed the overall population to persist. Therefore, the overall population was quite resilient to extinction; only in scenarios without any un-hunted areas did the population go extinct. However, the total and hunted populations did experience large declines over 100 years under moderate and high hunting pressure. In addition, when reserve area decreased, population losses and losses per unit area increased disproportionately. Furthermore, hunting disrupted the social structure of troops. The number of male turnovers and infanticides increased in hunted populations, while birth rates decreased and exacerbated population losses due to hunting. Finally, our results indicated that when more than 55% of the landscape was harvested at high (30%) rates, hunting yields, as measured by kilograms of biomass, were less than those obtained from moderate harvest rates. Additionally, hunting yields, expressed as the number of individuals hunted/year/km 2 , increased in proximity to un-hunted areas, and suggested that dispersal from un-hunted areas may have contributed to hunting sustainability. These results indicate that un-hunted areas serve to enhance hunting yields, population size, and population persistence in hunted landscapes. Therefore, spatial regulation of hunting via a reserve system may be an effective management strategy for sustainable hunting, and we recommend it because it may also be more feasible to implement than harvest quotas or restrictions on season length.

Natural and anthropogenic landscape features, such as rivers, mountain ranges, and roads can alter animal dispersal paths and movement patterns. Consequently landscape, through its effects on dispersal, may influence many ecological processes, including disease transmission, invasion dynamics, and gene flow. To investigate influences of landscape features on dispersal patterns of a large mammal, we captured and radiomarked 363 juvenile male white-tailed deer (Odocoileus virginianus), including 212 confirmed dispersers, in 2 topographically dissimilar study areas in Pennsylvania, USA. Dispersal azimuths were uniformly distributed in the western study area (WSA), where there was irregular, hilly topography. Mean dispersal azimuths paralleled ridge direction in the eastern study area, where long parallel ridges were aligned northeast-southwest. Major roads in both areas and a large river in the WSA were semipermeable barriers to dispersal of juvenile males; dispersal paths were less likely to intersect these linear features. Dispersal movements were direct and brief, typically lasting ,12 hours. For all dispersers, we found no evidence for preference or avoidance of establishing adult, postdispersal ranges in proximity to roads; however, deer that encountered roads near the terminus of their dispersal path were more likely to stop on the near side. Further, for deer that established postdispersal home ranges near major roads, these features influenced range placement such that locations were typically clustered on one side of the road. The influence of roads, rivers, and mountains on dispersal paths and postdispersal locations of white-tailed deer suggest that landscape-specific features should be considered in conservation and management of this and possibly other species of large mammals.

We estimated loss of butt-end leg bands on male wild turkeys (Meleagris gallapavo) captured in New York, Ohio, and Pennsylvania (USA) during December–March, 2006–2008. We used aluminum rivet leg bands as permanent marks to estimate loss of regular aluminum, enameled aluminum, anodized aluminum, and stainless steel butt-end leg bands placed below the spur. We used band loss information from 887 turkeys recovered between 31 days and 570 days after release (x¯ = 202 days). Band loss was greater for turkeys banded as adults (>1 yr old) than juveniles and was greater for aluminum than stainless steel bands. We estimated band retention was 79–96%, depending on age at banding and type of band, for turkeys recovered 3 months after release. Band retention was

The sex-age-kill (SAK) model is widely used to estimate abundance of harvested large mammals, including white-tailed deer (Odocoileus virginianus). Despite a long history of use, few formal evaluations of SAK performance exist. We investigated how violations of the stable age distribution and stationary population assumption, changes to male or female harvest, stochastic effects (i.e., random fluctuations in recruitment and survival), and sampling efforts influenced SAK estimation. When the simulated population had a stable age distribution and λ > 1, the SAK model underestimated abundance. Conversely, when λ < 1, the SAK overestimated abundance. When changes to male harvest were introduced, SAK estimates were opposite the true population trend. In contrast, SAK estimates were robust to changes in female harvest rates. Stochastic effects caused SAK estimates to fluctuate about their equilibrium abundance, but the effect dampened as the size of the surveyed population increased. When we considered both stochastic effects and sampling error at a deer management unit scale the resultant abundance estimates were within ±121.9% of the true population level 95% of the time. These combined results demonstrate extreme sensitivity to model violations and scale of analysis. Without changes to model formulation, the SAK model will be biased when λ ≠ 1. Furthermore, any factor that alters the male harvest rate, such as changes to regulations or changes in hunter attitudes, will bias population estimates. Sex-age-kill estimates may be precise at large spatial scales, such as the state level, but less so at the individual management unit level. Alternative models, such as statistical age-at-harvest models, which require similar data types, might allow for more robust, broad-scale demographic assessments.

Behavioral studies of white-tailed deer (Odocoileus virginianus) often assign mother–offspring relationships based on common capture of juveniles with adult deer, assuming that fawns associate closely with mothers. We tested this assumption using genetic parentage to assess mother–offspring relationships within capture groups based on data from 10 polymorphic microsatellite loci. At the 80% confidence level, we assigned maternity to 43% and 51% of juveniles captured with an adult female in 2 respective study areas. Capture with their mother did not differ by sex of juveniles in either study area, and limiting our analysis to capture groups that most represent family groups (i.e., one ad F with 1–3 juv) did not increase maternity assignment (35%). Our results indicate that common capture may be a poor indicator of mother–offspring relationships in many field settings. We recommend genetic verification of family relationships.

— Avian researchers often uniquely mark birds, and multiple estimators could be used to estimate population size using individually identified birds. However, most estimators of population size require that all sightings of marked birds be uniquely identified, and many assume homogeneous detection probabilities. Bowden's estimator can incorporate sightings of marked birds that are not uniquely identified and relax assumptions required of other estimators. I used computer simulation to evaluate the performance of Bowden's estimator for situations likely to be encountered in bird studies. When the assumptions of the estimator were met, abundance and variance estimates and confidence-interval coverage were accurate. However, precision was poor for small population sizes (N 75%) and multiple (≥8) sighting surveys were conducted. If additional birds are marked after sighting surveys begin, it is important to initially mark a large proporti...