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

Body weight (BW) is a critical component for monitoring animal weight gain, body condition, nutritional status. Remote animal weighing systems facilitate frequent collection of animal BW, however, datasets often contain spurious data. The objective of this study was to describe the utility of using a remote Walk-over-Weigh system and subsequent methods for data cleaning. Beef steers (n = 10) were tagged with Electronic RFID tags (EID) in an improved pasture (~12.1 hectares) containing Bermuda and Tall Fescue and inter-seeded with Annual Ryegrass and grazed from Feb. – Dec. 2020. Static chute weights (n = 80) were collected monthly, and a WOW system placed by the water to remotely collect BW (n = 5,466). Data were first loaded into Program R and scanned for spurious data using each of 2 primary approaches, 1) the whole herd and individual means ± 1 standard deviation (SD) calculated daily or over the entire trial and 2) each of 3 data smoothing algorithms, which included a quadratic growth model, cubic splines, and polynomial regression. Then, data with spurious observations removed were paired with static chute weights and fitted to a linear model to measure accuracy (mean bias) and precision (R2) of WOW data. Whole herd mean ± 1SD and individual daily mean ± 1SD identified 1,204 and 1,516 spurious data, with mean bias of -12.46 and -15.37 KG and R2 of 0.90 and 0.68, respectively. Smoothing functions identified 1,707, 4,684, and 4,776 spurious points, with a mean bias of 13.61, -19.78, and 12.58 KG, and R2 of 0.94, 0.70, and 0.87 for quadratic growth models, cubic splines, and polynomial regression, respectively. These results indicate the utility of using a simple WOW system to collect data for measuring growth curves and using weight data in a real-time fashion to make management and marketing decisions.

Context Obtaining accurate maps of landscape features often requires intensive spatial sampling and interpolation. The data required to generate reliable interpolated maps varies with spatial scale and landscape heterogeneity. However, there has been no rigorous examination of sampling density relative to landscape characteristics and interpolation methods.ObjectivesOur objective was to characterize the 3-way relationship among sampling density, interpolation method, and landscape heterogeneity on interpolation accuracy in simulated and in situ landscapes. MethodsWe simulated landscapes of variable heterogeneity and sampled at increasing densities using both systematic and random strategies. We applied each of three local interpolation methods: Inverse Distance Weighting, Universal Kriging, and Nearest Neighbor — to the sampled data and estimated accuracy (R2) between interpolated surfaces and the original surface. Finally, we applied these analyses to in situ data, using a normalized difference vegetation index raster collected from pasture with various resolutions.Results All interpolation methods and sampling strategies resulted in similar accuracy; however, low heterogeneity yielded the highest R2 values at high sampling densities. In situ results showed that Universal Kriging performed best with systematic sampling, and inverse distance weighting with random sampling. Heterogeneity decreased with resolution, which increased accuracy of all interpolation methods. Landscape heterogeneity had the greatest effect on accuracy.ConclusionsHeterogeneity of the original landscape is the most significant factor in determining the accuracy of interpolated maps. There is a need to create structured tools to aid in determining sampling design most appropriate for interpolation methods across landscapes of various heterogeneity.

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

Simple Summary Neospora caninum causes abortion and other reproductive challenges in livestock and leads to large economic losses every year. Wild pigs were evaluated for their potential role in the transmission of N. caninum, the parasite that causes neosporosis in cattle and other animals. Three assays were used to identify past or current exposure to N. caninum in wild pigs and histology was performed to determine if there was a pathology consistent with a N. caninum infection in the tissues that were evaluated. The following assays reported positive results: Kit A—67.8%, Kit B—12.5%, Indirect Fluorescent Antibody Test—84.1%, and Histology—0%. Importantly, the assays used in this study were not congruent with all duplicate samples or between test types and demonstrate the need for a more reliable test to identify N. caninum infections in wild pigs to better assess their potential role in disease transmission. Abstract Neospora caninum is a protozoan parasite, reported as a leading cause of cattle abortions and reproductive failure worldwide, costing the cattle industry approximately $1.3 billion annually. With wild pig (Sus scrofa) populations estimated at over six million in the United States, contact between wild pigs and livestock is inevitable, mainly because of the widespread geographic co-occurrence of the two species. As a known reservoir for numerous fungal, bacterial, viral and parasitic diseases, wild pigs are of particular importance for human and veterinary health relative to the prevention of infectious diseases. The seroprevalence of N. caninum in wild pig populations was previously documented in the United States, raising the question as to their exposure point of prevalence. This research screened 116 individual wild pigs for N. caninum using a variety of available assays. Using two different commercially available ELISA test kits, seroprevalence ranged from 12.5% to 67.8%. The Indirect Fluorescent Antibody Test resulted in our highest percent seroprevalence for these samples, at 84.1%. However, none of our samples showed any presence of N. caninum or associated pathologies via histological evaluation of representative tissues. Importantly, the assays used in this study were not congruent with all duplicate samples or between the test types used. The implications of these non-congruent results demonstrates that currently available testing assays produce variable results, underscoring the need for more reliable testing kits and a standardized methodology when assessing disease prevalence in wildlife, particularly for N. caninum in wild pigs, which impacts prevalence and comparability across studies.

Animal behavior plays a crucial role as an indicator of animal health and nutritional status and serves as an indicator of animal growth. The objective of this study was to build an ethogram describing behavior in grazing cattle. We collected video and accelerometer data from crossbred steers (n = 10) used as part of a larger grazing study on the HH Leveck Animal Research Center, Mississippi State, MS. Daily Diary accelerometers (Wildbyte® technologies, Swansea) were programmed to collect magnetometer and accelerometer data at 40 Hz and attached to the GPS collars fitted on the animals prior to their release into a 10-hectare pasture of Tall Fescue and Bermudagrass, overseeded with Annual Ryegrass. Automated camera traps (Bushnell Essential®) were synced with UTC time and programmed to record 30-second video clips when triggered. Approximately 387,000 accelerometer signals representing 161 minutes of behavior from 10 animals were recorded, and behavior classified according to 1 of 5 categories: traveling, foraging, resting, ruminating, and grooming (Kilgour et al., 2012). Categorized accelerometer data was used to train a random forest model (Liaw and Weiner, 2002) in Program R (R Core Team, 2020), which resulted in a model sensitivity of 0.97, 0.93, 0.90, 0.87, and 0.80 for Traveling, Foraging, Resting, Ruminating, and Grooming, respectively, and an overall model accuracy of 0.95. Behaviors were aggregated into behavior bouts, and a daily ethogram was calculated for March 2019. This revealed that the steers spent the most amount of time traveling, an average of 1,026 minutes per day. This behavior was followed, in the average length of time, by foraging and resting for 205 ± 52.8 minutes and 31.8 ± 28.2 minutes per day, respectively. These results indicate the ability to accurately build a behavioral ethogram for grazing cattle and warrant further study in future research and livestock management.

Previous research in feedlot studies has demonstrated that cattle feeding behavior is driven by internal metabolic processes and external environmental stimuli and serves as an indicator of animal health, nutritional status, and growth and feed quality and availability. However, technology has only recently allowed measurement of foraging behavior in grazing cattle. Objectives of this study were to measure frequency and duration of foraging bouts, meals, and total distance traveled during meals in grazing steers. The study was conducted as part of a larger grazing study on a 10-hectare Bermudagrass and Tall Fescue pasture, overseeded with Annual Ryegrass, located at the HH Leveck Animal Research Center, Mississippi State, MS. Using tri-axial accelerometers and GPS information from 10 crossbred steers, we examined foraging and meal bout frequency and duration and distance and speed traveled per meal for the period of March 2019. Observed animal behavior was used to train a randomforest model to predict foraging behavior, with model accuracy and sensitivity of 0.95 and 0.93, respectively. We found individual foraging bouts occurred on average 2,849 bouts per day and took on average 5.0 ± 1.8 min (range: 3–9 min), and that steers fed on average 205 ± 52.8 min/day (range: 120–270 min/day). Steers had an average of 9.5 ± 2.9 meals/day, that took on average, 89.3 ± 93.9 min/meal (range: 0.5–938.5 min/meal). Steers traveled an average of 412.4 ± 93.9 meters per meal, with an average foraging speed between 0 and 0.63 m/s. Traveling distance while foraging was positively correlated with meal length (0.83, P < 0.01) and foraging speed (0.70, P < 0.01). These results show that cattle grazing behavior can be accurately quantified in grazing cattle and warrants further research to examine associations between animal efficiency and performance, forage quality, and pasture management.

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

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

Poaching and the illegal wildlife trade (i.e., wildlife crime) are a multibillion-dollar global industry. The commercialization and overexploitation of wildlife caused by wildlife crime threaten biodiversity, particularly many of the species already on the cusp of extinction. Wildlife crime also leads to ecosystem collapse and loss of government revenues and threatens the strength and economic aspiration of developing nations. Efforts from wildlife law enforcement to prevent wildlife crime are a conservation necessity. The purpose of this chapter is to introduce the field of conservation forensics. Conservation forensics is an applied field of conservation crime science that fits within the broader frameworks of green and conservation criminology. This field of study applies hard science techniques used to gather wildlife crime data such as genetics, chemical analysis, geographical analysis, statistics, artificial intelligence, and computational modeling toward techniques that can directly benefit the efforts of law enforcement personnel involved in protecting imperiled wildlife. This chapter identifies and reviews tools and techniques that can help achieve the goals of conservation forensics: the prosecution of wildlife criminals and the prevention of wildlife crime to conserve biodiversity.

Tall fescue [Schedonorus arundinaceus (Schreb.) Dumort., nom. cons.] is a perennial cool‐season grass in which improved freeze tolerance could result in greater winterhardiness and persistence. Our objective was to evaluate survival and freeze‐tolerance thresholds of ‘Flecha’ summer‐dormant (SD) and ‘Texoma Max QII’ summer‐active (SA) tall fescue at seedling (1–2 leaves) and tillered (5–6 leaves) growth stages using controlled environment freezing chambers. Target temperatures ranged from 0 to −9 °C (seedlings) and 0 to −12 °C (tillered plants). Predicted lethal temperature at which 50% mortality occurs (LT50) was −5.7 and −5.5 °C for SA and SD seedlings, respectively, and −6.0 and −5.7 °C for SA and SD tillered plants, respectively. Based on these results, a controlled temperature chamber appears to be a useful tool for plant breeders when evaluating survival and freeze tolerance of SA and SD tall fescue germplasm at seedling and tillered growth stages.

Neospora caninum is a protozoan parasite, reported as a leading cause of cattle abortions and reproductive failure worldwide, costing the cattle industry approximately $1.3 billion annually. With wild pig (Sus scrofa) populations estimated at over six million in the United States, contact between wild pigs and livestock is inevitable, mainly because of the widespread geographic co-occurrence of the two species. As a known reservoir for numerous fungal, bacterial, viral and parasitic diseases, wild pigs are of particular importance for human and veterinary health relative to the prevention of infectious diseases. The seroprevalence of N. caninum in wild pig populations was previously documented in the United States, raising the question as to their exposure point of prevalence. This research screened 116 individual wild pigs for N. caninum using a variety of available assays. Using two different commercially available ELISA test kits, seroprevalence ranged from 12.5% to 67.8%. The Indirect Fluorescent Antibody Test resulted in our highest percent seroprevalence for these samples, at 84.1%. However, none of our samples showed any presence of N. caninum or associated pathologies via histological evaluation of representative tissues. Importantly, the assays used in this study were not congruent with all duplicate samples or between the test types used. The implications of these non-congruent results demonstrates that currently available testing assays produce variable results, underscoring the need for more reliable testing kits and a standardized methodology when assessing disease prevalence in wildlife, particularly for N. caninum in wild pigs, which impacts prevalence and comparability across studies.

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

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

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

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

Pecans (Carya illinoinensis) are an economically important specialty crop grown in the southern and southcentral parts of the United States. However, the invasive and exotic wild pig (Sus scrofa) is also distributed over this range, with some of the highest densities occurring in areas of pecan production. Using a before-after control-impact (BACI) study design, we quantified harvest efficiency of pecans in native groves and improved orchards damaged by wild pigs and in control areas that were not damaged. We found that 44% of pecans were not harvested in areas damaged by wild pigs. In control areas, 10% of pecans were not harvested due to the inefficiency of the pecan harvester. Therefore, the loss of pecans attributed to wild pig damage was 34%. This information was used to develop an online calculator ( https://nobleapps.noble.org/agcalculators/calculators/pecanloss ) that estimates production and economic losses, and can be used for making management decisions (e.g., wild pig control, second harvest of pecans, etc.).

The wild pig (Sus scrofa), an exotic and invasive species, has caused great concern at a global scale, particularly within agricultural landscapes. The objective of this study was to determine whether intensive trapping and wild pig removal resulted in a concomitant decrease in damage to rangelands. Removal of 356 wild pigs over 2 years showed an immediate reduction in rooting damage that carried over after trapping ceased. After only one trap session, rooting damage across the three sites was reduced 43–82% and total damage reduction from the beginning to the end of the project was 90%. With intensive trapping (1 pig/22.7 ha/year), damage may also be reduced on neighboring areas that are not being trapped, as indicated by data from our non-trapped units. Although we reduced rooting damage locally, and on nearby areas, large-scale, intensive control will be needed for the long-term effective reduction in damage and wild pig numbers because wild pigs have high reproductive rates, high survival, and can recolonize areas rapidly.

Switchgrass ( Panicum virgatum L.) is an important feedstock for biofuel production and also used for rangeland restoration and as a forage crop. Wide variability has been observed in switchgrass at both ecotypic and population levels. Variance component analysis can identify the relative contribution of different factors which can be used as guidance in selection of genotypes in breeding programs. The objectives of this study were to estimate and partition the sources of variance components and to estimate heritability of biomass yield in switchgrass. A total of 36 accessions including 31 plant introduction accessions collected from the Germplasm Resources Information Network (GRIN) and five improved populations developed at the Samuel Roberts Noble Foundation were used for estimating the variance components. Fourteen of these were lowland and 22 upland accessions. The accessions and populations were evaluated in Ardmore, Oklahoma from 2007 to 2011. Average biomass yield of lowland accessions was 2.41 ± 0.05 kg plant −1 and that of upland accessions was 0.57 ± 0.01 kg plant −1 . Biomass yield increased up to 526% from 2008 to 2010; however, it decreased up to 88% from 2010 to 2011 growing seasons due to severe drought. Variance component analysis revealed that accessions accounted for 48.5 and 37.2% of the total variation in the lowland and upland ecotypes, respectively. Biomass yield was moderately heritable for switchgrass (0.5) and for lowland (0.6) and upland (0.44) ecotypes, indicating that biomass yield could be improved through selection. In general, lowland ecotypes are more productive; however, a few upland accessions (e.g., PI 476294, PI 657660, PI 642193) were found productive even during dry years, albeit less biomass was produced than lowland ecotype.

Large carnivores are considered a primary source of mortality for many ungulate populations, but harvest by hunters is the primary means of population management. However, research is needed to evaluate how human predation risk influences observability (a surrogate to harvest susceptibility) of ungulates. We determined how hunting intensity and duration influence observation rates of white-tailed deer (Odocoileus virginianus) and how deer behavior (i.e., movement rate and resource selection) affects observation rates. We sampled 37 adult (≥2 yr) male deer at 2 levels of risk (i.e., low-risk = 1 hunter/101 ha; and high-risk = 1 hunter/30 ha) during 3 exposure periods (i.e., first, second, and third weekend of hunting) on a 1,861-ha property in Oklahoma, USA, during the 2008 and 2009 rifle deer-seasons. Observation rates (collared deer/hunter-hr/day) were greatest during the first weekend in both the low- and high-risk treatments, but declined each weekend thereafter in both treatments. Immediately prior to hunter observation, movement rate of observed collared deer was greater than that of unobserved collared deer, but only when hunting risk was high. Greater movement rates of deer in the high-risk treatment also led to a greater probability of observation. Hunters also had a greater probability of observing collared deer at higher elevations. Overall, deer modified their behavior to avoid detection by hunters. These results can be used to explain decreased observation rates to hunters and to modify harvest rates by altering timing and intensity of human predation risk during the recreational hunting season to help achieve population management goals through harvest. © 2014 The Wildlife Society.

Summary � The viral genome-linked protein, VPg, of potyviruses is involved in viral genome replication and translation. To determine host proteins that interact with Sugarcane mosaic virus (SCMV) VPg, a yeast two-hybrid screen was used and a maize (Zea mays) Elongin C (ZmElc) protein was identified. � ZmELC transcript was observed in all maize organs, but most highly in leaves and pistil extracts, and ZmElc was present in the cytoplasm and nucleus of maize cells in the presence or absence of SCMV. ZmELC expression was increased in maize tissue at 4 and 6 d post SCMV inoculation. When ZmELC was transiently overexpressed in maize protoplasts the accumulation of SCMV RNA was approximately doubled compared with the amount of virus in control protoplasts. � Silencing ZmELC expression using a Brome mosaic virus-based gene silencing vector (virusinduced gene silencing) did not influence maize plant growth and development, but did decrease RNA accumulation of two isolates of SCMV and host transcript encoding ZmeIF4E during SCMV infection. Interestingly, Maize chlorotic mottle virus, from outside the Potyviridae, was increased in accumulation after silencing ZmELC expression. � Our results describe both the location of ZmElc expression in maize and a new activity associated with an Elc: support of potyvirus accumulation.

Switchgrass (Panicum virgatum L.) cultivar research is focused on improvement in biomass yield and feedstock composition for bioenergy use. These improvements could be achieved by exploiting additive and non-additive effects of nuclear genes, as well as reciprocal differ- ences. The objective of this study was to evalu- ate the influence of reciprocal effects on bio - mass yield in lowland switchgrass. Forty-six biparental crosses and their reciprocals were evaluated at two locations in south-central Oklahoma using a honeycomb design. The trial was established in the summer of 2007, and year-end biomass yields were recorded during 2008 and 2009. The mean DNA content of the parents ranged from 1.96 to 3.70 pg, confirm - ing that the parental genotypes were tetraploid. Ten of the 46 crosses demonstrating favorable reciprocal effects (P £ 0.10) had >12% biomass yield advantage. The direction of reciprocal dif- ference was fairly consistent across locations by years. The relative advantage of using a cer- tain genotype as the female parent depended on the genetic background of the other geno- type used in crossing, indicating the complex genetics of reciprocal effects. The hybrids from parent 'LL43' in crosses with 'LL126' and 'LL22' produced an average of >40% biomass when used as the pollen parent rather than using it as the female. Evaluation of genotypes of inter- est for reciprocal effects by crossing with sev- eral other genotypes would help identify parents with favorable maternal effects for use in devel- opment of superior synthetic or hybrid varieties.

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

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

Visually estimating age of white-tailed deer (Odocoileus virginianus) using physical characteristics, commonly referred to as “aging on the hoof” (AOTH), has gained in popularity as part of management programs. However, AOTH has not been evaluated in reference to its accuracy or the accuracy of its users; and most importantly, AOTH is an unstandardized method for estimating age. To assess accuracy of AOTH as it currently is applied, we developed an accuracy examination consisting of a series of photographs of 70 wild, known-aged, antlered, male deer from south-central Oklahoma, USA, ranging in age from approximately 1.5 to ≥7.5 years. We distributed a pre-assessment questionnaire and the accuracy examination to registrants from the 2009 annual meeting of the Southeast Deer Study Group and to select individuals known to use AOTH. One hundred six wildlife professionals that commonly used the technique completed the assessment and examination. Overall accuracy averaged 36% when placing deer into year classes (min. = 16%; max. = 56%). Accuracy tended to be greater for younger year-classes (1.5–2.5 yr); accuracy generally declined as age increased. On average, 62%, 43%, 25%, 30%, 25%,15%, and 31% of deer were placed into the correct year-class for the 1.5, 2.5, 3.5, 4.5, 5.5, 6.5, and ≥7.5 year-classes, respectively. We provide the first known accuracy assessment by users of the AOTH technique. It appears that the AOTH technique lacks accuracy for placing deer into specific year-classes, which has implications for selective harvest decisions and research use. Accuracy may be improved by developing standardized protocols and criteria for using the technique and training observers. © 2013 The Authors Wildlife Society Bulletin published by Wiley Periodicals, Inc. on behalf of The Wildlife Society

Cereal rye (Secale cereale L.) is an important forage crop in the USA for stocker cattle (Bos sp.) production, thus making forage yield an important breeding objective for the crop. However, little information is known about the repeatability for forage yield in this crop. The objectives of this research were to: (i) estimate variance components for forage yield from long-term variety trials, (ii) estimate the repeatability for forage yield and (iii) relate this to breeding strategies for increased forage yield in rye. Trials were conducted over 14 years where 97 USA open-pollinated varieties (OPVs) were evaluated. Repeatability ranged from 0.57 to 0.86 when the data were analysed by year for the 3 years with significant genotype main effects. Possible explanations for the lack of significant genotype main effects are discussed. Practical implications of these findings indicate that the development of improved cultivars with greater forage yield will require improved methods of selection based on family performance rather than the current methods based primarily on single plant visual selection.