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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.

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.

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.

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

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.

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.

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.

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.

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, 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Over-browsing by white-tailed deer impedes forest regeneration, alters floristic and structural attributes of stands, and reduces biodiversity. Although numerous exclosure experiments have demonstrated negative impacts of deer on songbirds at small spatial scales, the effects of deer on avian communities at large spatial and temporal scales remains poorly understood. We integrated data from the Breeding Bird Survey with historic information on deer abundance in a multi-species hierarchical model to assess spatio-temporal relationships between deer and bird abundances across the state of Pennsylvania between 1981 and 2015. Our results provide evidence of strong links between deer and both avian functional groups and individual species, depending upon the extent each relied upon particular forest strata. Specifically, species that forage or nest near the ground were more negatively affected by deer than canopy-associated species. Likewise, mature-forest species were more sensitive to deer than successional-forest species or habitat generalists. With only a few exceptions, species-level responses to deer were consistent with group-level effects. Given the diverse suite of spatio-temporal stressors impacting migratory songbirds throughout their annual cycle, it was not surprising that long-term population trends of focal species were not significantly associated with deer abundance. Our findings, however, provide evidence that deer play an important role in songbird community structure, as mediated by the reliance of individual species upon particular forest strata and, as such, should be considered within the context of forest bird conservation.

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 (

Effective deer management must consider diverse stakeholder values. From 2006 to 2011, the Pennsylvania (USA) Game Commission implemented citizen advisory committees (CACs) to measure deer–human conflicts and tolerance for deer populations in each wildlife management unit. There was a general lack of public interest in participating in CACs. Key stakeholder groups were often absent and CACs exhibited a strong hunter bias. Although the CAC process seemed to benefit those involved, the scope was limited and likely did not represent the values and attitudes of the entire citizenry within the wildlife management unit. As a result of this CAC experience, the Pennsylvania Game Commission moved to a citizen survey in 2011 to ensure all interests are represented as the future success of deer management depends on greater understanding of the values and attitudes of every stakeholder. © The Wildlife Society, 2012

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.

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.

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.

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.

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.

Dispersal distances and their distribution pattern are important to understanding such phenomena as disease spread and gene flow, but oftentimes dispersal characteristics are modeled as a fixed trait for a given species. We found that dispersal distributions differ for spring and autumn dispersals of yearling male white-tailed deer (Odocoileus virginianus) but that combined data can be adequately modeled based on a log-normal distribution. We modeled distribution of dispersal distances from 3 distinct populations in Pennsylvania and Maryland, USA, based on the relationship between percent forest cover and mean dispersal distance and the relationship between mean and variance of dispersal distances. Our results suggest distributions of distances for dispersing yearling male white-tailed deer can be modeled by simply measuring a readily obtained landscape metric, percent forest cover, which could be used to create generalized spatially explicit disease or gene flow models.

Dispersal of yearling male white-tailed deer (Odocoileus virginianus) can have profound effects on population demographics and can adversely affect population estimates and management objectives. The relationship among population demographics, social pressures, and dispersal ecology is not clear and warrants scientific evaluation. The age structure and sex ratio of the white-tailed deer population at Chesapeake Farms, Maryland, USA, changed after implementation of quality deer management (QDM). Following Rosenberry's (1997) pre-QDM study on white-tailed deer dispersal, we conducted a post-QDM study on white-tailed deer dispersal at Chesapeake Farms. The objectives of our study were 1) to compare pre- and post-QDM emigration, immigration, survival, and behaviors of yearling males, 2) to evaluate inbreeding avoidance and sexual competition hypotheses as mechanisms of dispersal through behavioral comparisons of dispersers and nondispersers, and 3) to evaluate the maternal aggression hypothesis by co...

Animal dispersal patterns influence gene flow, disease spread, population dynamics, spread of invasive species, and establishment of rare or endangered species. Although differences in dispersal distances among taxa have been reported, few studies have described plasticity of dispersal distance among populations of a single species. In 2002‐2003, we radiomarked 308 juvenile (7- to 10-month-old), male white-tailed deer (Odocoileus virginianus) in 2 study areas in Pennsylvania. By using a meta-analysis approach, we compared dispersal rates and distances from these populations together with published reports of 10 other nonmigratory populations of white-tailed deer. Population density did not influence dispersal rate or dispersal distance, nor did forest cover influence dispersal rate. However, average (r 2 ¼ 0.94, P , 0.001, d.f. ¼ 9) and maximum (r 2 ¼ 0.86, P ¼ 0.001, d.f. ¼ 7) dispersal distances of juvenile male deer were greater in habitats with less forest cover. Hence, dispersal behavior of this habitat generalist varies, and use of landscape data to predict population-specific dispersal distances may aid efforts to model population spread, gene flow, or disease transmission.

Use of reported harvests as an index to actual harvest assumes that the proportion of harvest reported is equal for all types of animals and hunters and does not vary spatially or temporally. We modeled reporting rates of white-tailed deer (Odocoileus virginianus) harvest to determine whether they varied by year, deer management unit (DMU), type of deer (antlered or antlerless), or sex. During rifle seasons in Pennsylvania, USA, from 1990 to 2001, reporting rates varied by year, DMU, and type of deer (antlered or antlerless). Harvest estimates of antlered and antlerless deer were precise for both statewide (CV

Surveillance programs for Chronic Wasting Disease (CWD) in free-ranging cervids often use a standard of being able to detect 1% prevalence when determining minimum sample sizes. However, 1% prevalence may represent >10,000 infected animals in a population of 1 million, and most wildlife managers would prefer to detect the presence of CWD when far fewer infected animals exist. We wanted to detect the presence of CWD in white-tailed deer (Odocoileus virginianus) in Pennsylvania when the disease was present in only 1 of 21 wildlife management units (WMUs) statewide. We used computer simulation to estimate the probability of detecting CWD based on a sampling design to detect the presence of CWD at 0.1% and 1.0% prevalence (23–76 and 225–762 infected deer, respectively) using tissue samples collected from hunter-killed deer. The probability of detection at 0.1% prevalence was

Sexual competition and aggression by adult females have been hypothesized to prompt dispersal by male white-tailed deer (Odocoileus virginianus). We observed behavioral interactions of 21 yearling males (14 dispersers and 7 nondispersers) at Chesapeake Farms during the early part of the breeding season prior to actual breeding. Interactions with adult males and females constituted a small portion of all interactions and yearling males were similarly subordinate to adults. Dispersers participated in breeding-season behaviors with yearling males more often than nondispersers did (P = 0.005), and tended to be more subordinate than nondispersers (P = 0.095). Behavioral differences related to sexual competition with other yearlings appeared to be correlated with dispersal by yearling males at Chesapeake Farms. We recommend that both sexual competition and aggression by adult females be considered in future attempts to understand the dispersal behavior of white-tailed deer.

The Brownie tag-recovery model is useful for estimating harvest rates but assumes all tagged individuals survive to the first hunting season; otherwise, mortality between time of tagging and the hunting season will cause the Brownie estimator to be negatively biased. Alternatively, fitting animals with radio transmitters can be used to accurately estimate harvest rate but may be more costly. We developed a joint model to estimate harvest and annual survival rates that combines known-fate data from animals fitted with transmitters to estimate the probability of surviving the period from capture to the first hunting season, and data from reward-tagged animals in a Brownie tag-recovery model. We evaluated bias and precision of the joint estimator, and how to optimally allocate effort between animals fitted with radio transmitters and inexpensive ear tags or leg bands. Tagging-to-harvest survival rates from >20 individuals with radio transmitters combined with 50–100 reward tags resulted in an unbiased and precise estimator of harvest rates. In addition, the joint model can test whether transmitters affect an individual's probability of being harvested. We illustrate application of the model using data from wild turkey, Meleagris gallapavo, to estimate harvest rates, and data from white-tailed deer, Odocoileus virginianus, to evaluate whether the presence of a visible radio transmitter is related to the probability of a deer being harvested. The joint known-fate tag-recovery model eliminates the requirement to capture and mark animals immediately prior to the hunting season to obtain accurate and precise estimates of harvest rate. In addition, the joint model can assess whether marking animals with radio transmitters affects the individual's probability of being harvested, caused by hunter selectivity or changes in a marked animal's behavior.

In community-level ecological studies, generally not all species present in sampled areas are detected. Many authors have proposed the use of estimation methods that allow detection probabilities that are