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Supplemental feeding of wild ungulates has long been and remains a common practice across Europe and North America. Yet by drawing animals together, supplemental feeding can have unintended, negative effects on individual species and broader ecological processes. These include increased risk of disease transmission, intraspecific and interspecific competition, and predation, which are of management concern for white‐tailed deer (Odocoileus virginianus) in the southeastern United States given the arrival of nonnative wild pigs (Sus scrofa) and coyotes (Canis latrans). We conducted a field experiment between March and July of 2021 to assess the effects of supplemental feeding on spatiotemporal activity patterns of deer and wild pigs at wildlife feeders, and space use of coyotes in the Piedmont region of South Carolina, USA. We observed support for our hypothesis that interspecific competition through increased visitation by larger groups of competitor species reduces use of foraging sites by other subordinate ungulates, where feeders highly visited by wild pigs were rarely visited by deer. While adult deer and wild pigs generally did not shift their temporal activity patterns at feeders, juvenile temporal activity shifted to more frequent visits of feeders during the night, supporting our hypothesis that supplemental feed could increase risk to predator exposure, as coyotes tend to be active during crepuscular hours. Our findings suggest that supplemental feed put out to encourage deer activity could actually deter deer if wild pigs occupy that area, and has potential negative demographic effects if juveniles are at increased risk of predation. Collectively, based on our data, we do not recommend supplemental feeding in the southeastern United States where white‐tailed deer, coyotes, and wild pigs co‐occur. More broadly, given how widespread the legal use of supplemental feed remains across the United States, we encourage landowners and policymakers to consider the full suite of potential direct and indirect, short‐term and long‐term negative impacts supplemental feeding can have on both target and nontarget wildlife populations. We conducted a field experiment to assess the effects of supplemental feeding on spatiotemporal activity patterns of deer and wild pigs at wildlife feeders, and found that feeders highly visited by wild pigs were rarely visited by deer. In addition, young deer shifted to more frequent visits of feeders during the night, increasing their risk of encountering coyotes that tend to be active during crepuscular hours. Thus, our findings suggest that putting supplemental feed out to encourage deer activity could deter deer if wild pigs occupy that area, and the practice has potential negative demographic effects if fawns are at increased risk of predation.

Being opportunistic omnivores, wild pigs (Sus scrofa) readily feed on edible garbage. Given the presence of substantial volumes of edible food waste, large multi‐county and regional municipal sanitary waste landfills constitute attractive forage resources for pigs, providing a year‐round anthropogenic source of potentially high‐quality forage. Our objective was to assess the effects that a large regional landfill has on the local pigs foraging in that facility's waste disposal cells. The landfill, located on the United States Department of Energy's Savannah River Site (SRS) in South Carolina, USA, became operational in 1998 and pigs began foraging there in 2001. By 2009 >100 pigs/night were observed foraging in the landfill, suggesting landfill establishment may have important consequences for population dynamics, public safety, and disease transmission. We evaluated changes in body mass, fetal litter size, numbers of pigs removed, and wild pig‐vehicle collisions (WPVCs) before (1980–2000) and after (2001–2019) pigs began foraging in the landfill on SRS. Body mass during the after period increased to a greater extent for pigs in the vicinity of the landfill compared to pigs on the rest of SRS. Fetal litter size increased for pigs in the vicinity of the landfill, whereas it remained unchanged on the rest of SRS. Our density surrogate (number of pigs harvested) increased around the landfill during the after period by 2.9 times, whereas on the rest of the site it only increased by 53%. No WPVCs occurred adjacent to the landfill before 2001, but WPVCs increased along the 2 major roads bordering the landfill after 2001. Effects of sanitary waste landfills on wild pig populations scavenging there can present unique challenges to population management, control, public safety, and disease transmission. Potential approaches to address these challenges could be exclusion fencing to prevent access to the landfill's waste disposal cells or enhanced placement of waste cell covers to reduce access. © 2021 The Wildlife Society. Wild pigs foraging in a municipal solid waste landfill had larger body mass and litter sizes than pigs without access, resulting in greater density and incidence of wild pig vehicle collisions on roads adjacent to the landfill. These factors amplify the difficulty of controlling wild pig populations around landfills, and research should focus on exploring the relative costs and benefits of exclusion versus ways to minimize the attractiveness of landfills to wild pigs.

Estimating survival and cause‐specific mortality of male eastern wild turkeys (Meleagris gallopavo silvestris) is important for understanding population dynamics and implementing appropriate harvest management. To better understand age‐specific estimates of annual survival and harvest rates, we captured and marked male wild turkeys with leg bands (n= 311) or bands and transmitters (n= 549) in Georgia, Louisiana, North Carolina, and South Carolina, USA, during 2014–2022. We fitted time to event models to data from radio‐marked birds to estimate cause‐specific mortality and annual survival. We used band recovery models incorporating both band recovery and telemetry data to further investigate harvest rates and survival. Annual survival from known‐fate models in hunted populations was 0.54 (95% CI = 0.49–0.59) for adults and 0.86 (95% CI = 0.81–0.92) for juveniles. Cause‐specific mortality analysis produced an annual harvest estimate of 0.29 (95% CI = 0.24–0.33) for adults and 0.02 (95% CI = 0.01–0.03) for juveniles, whereas predation was 0.15 (95% CI = 0.10–0.20) and 0.12 (95% CI = 0.08–0.17), respectively. Annual survival for adult males in a non‐hunted population was 0.83 (95% CI = 0.72–0.97). Survival rate was negatively correlated with harvest rate, indicating harvest was an additive mortality source. Annual survival from band recovery models was 0.40 (95% CI = 0.37–0.44) for adults and 0.88 (95% CI = 0.81– 0.93) for juveniles, whereas annual harvest estimates were 0.24 (95% CI = 0.23–0.25) for adults and 0.04 (95% CI = 0.03–0.05) for juveniles. Both models suggested no differences in annual survival across years or among study areas, which included privately owned and public properties. Harvest was an additive mortality source for male wild turkeys, suggesting that managers interested in increasing annual survival of adult males could consider ways of reducing harvest rates. To better understand age‐specific estimates of annual survival and harvest rates for male wild turkeys, we captured and marked male wild turkeys with leg‐bands (n = 311) or bands and transmitters (n = 549) in Georgia, Louisiana, North Carolina, and South Carolina during 2014 – 2022. Annual survival and harvest estimates varied by age class and whether the population was exposed to harvest. Our findings indicate that harvest was clearly an additive mortality source for male wild turkeys, suggesting that managers interested in increasing the annual survival of adult males could consider ways of reducing harvest rates.

Changing predator communities have been implicated in reduced survival of white‐tailed deer (Odocoileus virginianus) fawns. Few studies, however, have used field‐based age‐specific estimates for survival and fecundity to assess the relative importance of low fawn survival on population growth and harvest potential. We studied white‐tailed deer population dynamics on Tensas River National Wildlife Refuge (TRNWR) in Louisiana, USA, where the predator community included bobcats (Lynx rufus), coyotes (Canis latrans), and a restored population of Louisiana black bear (Ursus americanus luteolus). During 2013–2015, we radio‐collared and monitored 70 adult (≥2.5 yrs) and 21 yearling (1.5‐yr‐old) female deer. Annual survival averaged 0.815 (95% CI = 0.734–0.904) for adults and 0.857 (95% CI = 0.720–1.00) for yearlings. We combined these estimates with concurrently collected fawn survival estimates (0.27; 95% CI = 0.185–0.398) to model population trajectories and elasticities. We used estimates of nonhunting survival (annual survival estimated excluding harvest mortality) to project population growth (λ) relative to 4 levels of harvest (0, 10%, 20%, 30%). Finally, we investigated effects of reduced fawn survival on population growth under current management and with elimination of female harvest. Despite substantial fawn predation, the deer population on TRNWR was increasing (λ = 1.06) and could sustain additional female harvest; however, the population was expected to decline at 20% (λ = 0.98) and 30% (λ = 0.94) female harvest. With no female harvest, the population was projected to increase with observed (λ = 1.15) and reduced fawn survival (λ = 1.02), but the population could not sustain current female harvest (10%) if fawn survival declined (λ = 0.90). For all scenarios, adult female survival was the most elastic parameter. Given the importance of adult female survival, the relative predictability in response of adult survival to harvest management, and the difficulty in altering fawn survival, reducing female harvest is likely the most efficient approach to compensate for low fawn survival. On highly productive sites such as ours, reduction, but not necessarily elimination, of harvest can mitigate effects of low fawn survival on population growth. © 2020 The Wildlife Society. White‐tailed deer population dynamics on Tensas River National Wildlife Refuge in Louisiana, USA, where the predator community included bobcats, coyotes, and a restored population of Louisiana black bear are characterized by high fecundity rates, low non‐harvest mortality for adults and yearlings, and low probability of survival for fawns. Given the importance of adult female survival to population growth, the relative predictability in response of adult survival to harvest management, and the difficulty in altering fawn survival, reducing female harvest is likely the most efficient approach to compensate for low fawn survival.

Baiting is a fundamental strategy for the global management of wild pigs (Sus scrofa); however, little information exists on how anthropogenic bait affects wild pig movements on a landscape. We investigated factors that are important in determining the spatial area of attraction for wild pigs to bait (‘area of influence’ of a bait site) using data from Global Positioning System (GPS) collars and locations of bait sites. We monitored movements of wild pigs in 2 distinct study areas in the United States from February to September 2016 and used locational data using GPS collars to analyze the influence of habitat quality (dependent on site), home range size, number of bait sites in the home range, distance to a bait site, and sex in relation to movement in time and space. We determined the average area of influence by calculating the area of a circle with the radius as the average maximum distance travelled by wild pigs to reach a bait site. The average area of influence for our bait sites was 6.7 km2(or a radius of approximately 1.5 km), suggesting a bait spacing of approximately 1.5 km would be adequate to capture visitation by most wild pigs and a spacing of 3 km could allow substantial visitation while minimizing redundant effort depending on the spatial structure of the populations. Eighty percent of wild pigs first visited bait sites within 8.9 days after bait deployment; and they visited earlier when their home range size was larger. As the number of bait sites in an individual's home range increased, individual pigs visited more bait sites, and the probability of a visit increased dramatically up to approximately 5 bait sites and much less thereafter. Wild pigs travelled farther distances to visit bait sites in lower quality habitat. Our results support the hypothesis that habitat quality can mediate the efficacy of baiting programs for wildlife by influencing their movement patterns and motivation to use anthropogenic resources. Our results suggest wild pigs will travel extensively within their home range to visit bait sites, and that in lower quality habitat, most animals will find bait sites more quickly. Determining the area of influence of bait sites can increase the efficacy of planning and monitoring management programs. Our study provides new information to help managers plan baiting designs to attract the greatest number of pigs. © 2020 The Wildlife Society. We identified factors principal in defining the area of influence of a bait site, or the spatial area of attraction, and found that most wild pigs will reach bait sites more quickly in lower quality habitat, likely as a result of increased travel in locations with inadequate resources. Our recommendations work to help managers efficiently plan and monitor baiting designs for maximal wild pig attraction.

Effective conservation of group-living forest wildlife requires information on how forest age moderates population parameters. Relationships between forest age and demographics can guide long-term management for wildlife populations that are expanding in relatively young second-growth forests in response to ongoing habitat management. We examined how forest age moderates effects of group density on long-term trends in group size and fledgling production in the endangered red-cockaded woodpecker Dryobates borealis(RCW) on the Savannah River Site, SC (SRS). We used 32 years of RCW monitoring data and generalized additive models to: 1) model long-term changes in average RCW group size and fledgling production; and 2) model effects of neighboring group density and neighboring group sizes across a gradient of forest age within 800 m of a group's cavity tree cluster. Average fledgling production oscillated over 2–3 year periods, but longer term evaluation indicated oscillations dampened and average fledgling production slightly decreased over time. Average group size fluctuated abruptly over 2–3 year periods from 1985 to 1994, but longer term evaluation indicated a general increase in group sizes from 1985 to 1994, followed by declines from 1995 to 2007, and a steady increase after 2010. Average fledgling production increased in response to neighboring group density but decreased as neighboring group sizes increased. In contrast, average group sizes increased in response to greater neighboring group density and neighboring group sizes. Stand age did not affect these relationships. Collectively, these results suggest forest age does not directly moderate effects of neighboring group density or group sizes on long-term average group size and fledgling production in the SRS RCW population. Although forest structure has been linked to increased RCW group sizes and productivity, our results suggest that with ongoing habitat management, long-term changes in group size and fledgling production will be driven primarily by group density conditions rather than changing forest age.

The robust dispersal capability of the coyote (Canis latrans) would suggest a pattern of widespread gene flow across North America, yet historical legacies, dispersal barriers, and habitat affinities may produce or reinforce genetic structure. In the northeastern United States, some coyotes carry genetic signatures from past hybridization events with eastern wolves (C. lupus lycaon). These so‐called “coywolves” may have differential predation or competitive success compared with the western origin coyotes with whom they share the contemporary landscape. We sampled coyote populations from New York (n= 156) and Wyoming, USA (n= 8) in 2006–2007 and from South Carolina, USA, in 2010 and confirmed regional genetic structure among these coyote populations. Then, within the putative contact zone between the northeastern and western coyote colonization fronts (New York State), we evaluated evidence for broad‐ and fine‐sale genetic structure, and a genetic gradient among New York coyotes using a suite of spatial genetic analyses. Although broad‐scale analyses indicated New York coyotes were highly intermixed, subtle isolation‐by‐distance was detected, and local spatial autocorrelation indicated potentially shorter dispersal distances and larger group sizes for coyotes in the Northeastern Highlands (Adirondack Mountains and foothills). Yet we failed to detect a distinct contact zone between 2 coyote types in New York, indicating that local abundance and ecological context rather than genetic lineage are likely to determine the local ecological effects of coyotes in this region. We suggest that the contact zone between coyote colonization fronts has either eroded or moved further south. © 2019 The Wildlife Society. Differences in the ecology of the coyote among the southern agricultural and northern forested areas of New York, USA, have been attributed to its legacy of colonization both from south of the Great Lakes and from north of the Great Lakes, the latter containing evidence of wolf hybridization. However, a spatial genetic analysis of neutral markers indicate that New York State contains a single genetically homogenous population of coyotes.

Eastern wild turkeys (Meleagris gallopavo silvestris) use a polygynous‐promiscuous mating system, wherein males compete for mating opportunities and communicate with females via courtship behaviors. One courtship behavior is vocalization (gobbling), which attracts females and signals dominance to other males. However, temporal variation in gobbling activity may be influenced by external stimuli, environmental variation, and hunter activity. Gobbling activity is a key determinant of hunter satisfaction, and gobbling chronology is often used by state agencies to inform regulatory processes. To identify factors influencing gobbling activity, we evaluated daily gobbling chronology on 3 sites in South Carolina, USA (Webb Wildlife Management Area [WMA] Complex, Savannah River Site, Crackerneck WMA) with different levels of hunter activity. We used autonomous recording units (ARUs; n= 45) across 8,280 days to collect 53,937 hours of ambient sound recordings and identified 68,426 gobbles. Gobbling activity varied daily and site interacting with minutes since sunrise best predicted daily gobbling activity. We noted distinct differences in predicted numbers of gobbles between hunted sites and an unhunted site, suggesting that hunting may be an important determinant of gobbling activity. Across our study sites, we observed that ≥72% of gobbling activity occurred between 30 minutes before and 60 minutes after sunrise. We found no clear evidence of well‐defined unimodal or bimodal peaks in daily or weekly gobbling activity. Across sites, <44% of gobbling activity occurred during legal hunting seasons in South Carolina, with between 30% and 48% of gobbling activity occurring after legal hunting seasons. Because hunter satisfaction is primarily influenced by gobbling activity, wildlife managers in South Carolina may consider adjusting dates of turkey hunting seasons to correspond hunting with periods when most gobbling occurs. © 2018 The Wildlife Society. Our results indicated that eastern wild turkey gobbling activity was best predicted by time since sunrise while varying according to hunting regimes. Additionally, most gobbling occurred outside of the current public land hunting season framework in South Carolina. We suggest that accurate assessments of gobbling chronology, combined with reproductive phenology, harvest rates of males, and measurements of hunter satisfaction be considered by agencies when establishing season frameworks and bag limits.

As a result of substantial ecological and economic damage attributed to wild pigs (Sus scrofa), there is international interest in using pharmaceutical baits to control populations. To assess the efficacy and specificity of baiting programs, chemical biomarkers can be used to evaluate uptake of pharmaceutical baits. Rhodamine B (RB) is known to be an effective biomarker in wild pigs. However, significant data gaps exist regarding the minimum effective dosage and persistence of RB in wild pigs. We used a controlled double‐blind study experiment conducted in spring of 2014 on the Savannah River Site, Aiken, South Carolina, USA, wherein we administered a one‐time dose of RB at 3 treatment levels (5 mg/kg, 15 mg/kg, or 30 mg/kg) to 15 captive pigs, with 5 pigs/treatment group to investigate persistence of RB. Facial vibrissae were collected pre‐RB ingestion as a control and every 2 weeks post‐RB ingestion for 12 weeks. We examined samples for RB presence and used a generalized linear mixed model (GLMM) to determine the influence of treatment dose on persistence of RB. Additionally, we measured distance moved by the RB mark away from the vibrissae root and used a GLMM to assess movement rates of RB bands along growing vibrissae. We found consistently greater persistence of RB in the 15‐ and 30‐mg/kg treatments across the sampling period. A significant, positive movement trend in RB bands was observed within the 15 mg/kg and 30 mg/kg groups. Based on our results, a 15 mg/kg dosage can be considered a minimum effective dose for wild pigs and will reliably produce a detectable RB mark up to and likely beyond 12 weeks after ingestion. © 2017 This article is a U.S. Government work and is in the public domain in the USA. Rhodamine B (RB) can be used to assess the efficacy and specificity of pharmaceutical baiting programs; however, data gaps exist regarding the minimum effective dose and persistence of RB in wild pigs. We found that a 15 mg/kg dosage was the minimum effective dose for wild pigs and will reliably produce a detectable RB mark up to and likely beyond 12 weeks after ingestion.

The eastward expansion of coyotes (Canis latrans) has brought the species into ecosystems and landscapes different from those it historically occupied, yet little is known about the reproductive biology of coyotes in the southeastern United States or the effects of exploitation on reproduction in coyotes. Our objective was to quantify litter size, pregnancy rate, and fecundity in an essentially unexploited coyote population in South Carolina, USA and to evaluate the effect of exploitation on these parameters. We examined reproductive tracts from 235 female coyotes trapped during 2010–2012. Placental scars from coyotes trapped during 2010 indicated that prior to trapping (2009), pregnancy rates were zero for juveniles, 0.25 for yearlings, and 0.389 for adults. Litter size for adults during 2009 averaged 5.4 pups/female, resulting in fecundity of 2.1 pups/female. The number of coyotes trapped was similar among years, indicating that the population recovered following trapping each year, but it shifted toward a younger age structure during trapping. However, although pregnancy rate, litter size, and fecundity of adults all tended to increase from pre‐trapping (2009) through the last trapping period (2011–2012), differences were not significant for this or any other age class. Fecundity of the population did not significantly increase during the first year of trapping (2010) but was lower during the last trapping period (2011–2012; 0.56 ± 0.15 [95% CL]) than prior to trapping (0.90 ± 0.15 [95% CL]). Thus, we observed only weak evidence for compensatory reproduction in response to trapping pressure and conclude that the increase in the juvenile component of the population was attributable primarily to immigration from neighboring areas rather than in situreproduction. This increased representation of juveniles in the population, which rarely bred, coupled with a concurrent decrease in adults, which accounted for 59.2% of breeding, explains the reduction in population fecundity. High immigration rates as indicated herein render coyote populations extremely difficult to control. © 2017 The Wildlife Society. Coyotes are believed to exhibit compensatory reproduction wherein pregnancy rates and litter sizes, and hence fecundity, increase in response to control efforts. We found that fecundity actually declined following control, indicating immigration rather than reproduction was primarily responsible for population recovery and suggesting control programs must be large enough to influence the regional pool of immigrants.

Despite efforts to reduce their effects on livestock and native ungulates within the southeastern United States, coyotes (Canis latrans) can recover from control programs. It is unknown how coyotes compensate for high mortality following trapping, so there is great interest to identify methods that can provide insight into coyote response to intensive trapping. To investigate if population genetic tools can decipher how coyotes recover from intensive trapping, we combined an empirical test of how genetic differentiation, diversity, and familial structure changed following trapping on the Savannah River Site (SRS), South Carolina, USA, with spatially explicit genetic simulations. The pre‐ and post‐trapping periods had similar genetic diversities and were not genetically differentiated as expected by either compensatory reproduction or immigration from a single genetic source. The post‐trapping coyote populations exhibited weaker signatures of philopatry with little evidence for increased dispersal distances of young coyotes, which suggests immigration caused a decrease in familial structure. Our simulations indicated that spatial autocorrelation coefficients and observed heterozygosities change as immigration increases, whereas population differentiation, allelic richness, and displacement distances do not. Collectively, our results suggest that coyotes recover from intensive trapping via reproduction and immigration, which likely makes preventing compensation difficult. Monitoring post‐trapping populations may offer more insight into maximizing the effectiveness of control efforts, and based on our simulations, population genetics can provide critical information about the amount of compensatory immigration following trapping. © 2017 The Wildlife Society. With a combination of spatial genetic analysis and simulations, we found that coyotes on the Savannah River Site in South Carolina recover from culling via both compensatory reproduction and immigration. Simulations indicated that spatial genetic analyses can detect subtle changes in genetic structure following culling, but each statistic has different sensitivities to the amount of immigration following culling.

Changing predator communities have potential to complicate management focused on ensuring sustainable white‐tailed deer (Odocoileus virginianus) populations. Recent research reported that predation on neonates by coyotes (Canis latrans) and bobcats (Lynx rufus) can limit recruitment. However, no research has been conducted in areas of the southeastern United States with 3 sympatric neonate predators such as coyote, American black bear (Ursus americanus), and bobcat. Our objectives were to estimate neonate survival rates, identify causes of neonate mortality, and determine which biological and landscape characteristics were related to neonate survival. During 2013–2015, we captured 70 neonates with the aid of vaginal implant transmitters on Tensas River National Wildlife Refuge in northeastern Louisiana, USA. We monitored neonates every 8 hours until 6 weeks of age and daily until 12 weeks of age, and assigned cause of death from field and DNA evidence. Survival of neonates to 12 weeks was 0.271 (95% CI = 0.185–0.398). Of 51 mortalities, 45 (88%) were attributed to predation, 4 (8%) to starvation, 1 (2%) to other causes, and 1 (2%) to unknown causes. We used an information‐theoretic approach to compare Cox proportional hazards models containing various combinations of biological and habitat covariates. Our best‐supported model contained sex, mass at birth, distance to cropland, young reforestation (planted 2000–2009), and old reforestation (planted 1980–1989). Based on hazard ratios, survival was 81% higher for males than females, and survival increased 81% with every 1‐kg increase in birth mass. Survival increased 8% for every 100‐m increase in distance from cropland or young reforestation, and decreased 11% with every 100‐m increase in distance from old reforestation, which may be a result of spatial variation in predator distribution. Our results emphasize the importance of site‐specific monitoring of neonate recruitment rates in areas with burgeoning predator communities. We conclude, however, that although predation pressure was high, survival rates were similar to those observed in 2‐predator systems in the region, suggesting the possibility that an upper limit to predation rates may exist for white‐tailed deer neonates. © 2017 The Wildlife Society. White‐tailed deer neonate survival in Louisiana was low compared to research conducted throughout the United States, and black bear predation was the greatest source of mortality for neonates. We conclude that although predation pressure was high, survival rates were similar to those observed in 2‐predator systems in the region, suggesting the possibility that an upper limit to predation rates may exist for white‐tailed deer neonates.

Coyote (Canis latrans) predation on white‐tailed deer (Odocoileus virginianus) fawns in southeastern North America has led to deer population declines in some areas. Research or management efforts initiated in response to coyote predation on fawns have primarily focused on implementation of reduced antlerless deer harvest or coyote control to mitigate population declines. Vegetation characteristics may influence coyote hunting efficiency, but the potential influence of land cover at large scales in the southeastern United States is underexplored. We investigated whether mortality risk was affected by landscape characteristics within fawn home ranges for a sample of 165 fawns on the United States Department of Energy's Savannah River Site (SRS), South Carolina, 2007–2012. We monitored fawns every 8 hours to ≥4 weeks of age and 1–3 times daily to 12 weeks of age. We included only surviving or coyote‐predated fawns in the dataset. The most supported model describing hazard ratios included the length of edge (i.e., area where 2 land cover types joined) in fawn home ranges. Probability of coyote predation increased 1.26 times for each 968‐m decrease in edge within a fawn's simulated home range (29.1‐ha circular buffer) under this model. Further, fawns with the least edge in their home ranges were >2 times more likely to be depredated by a coyote than fawns with the greatest edge availability. Support for other models was relatively low, but informative variables (e.g., mean patch fractal dimension, Shannon's diversity index, mean forest patch size) supported a general trend that as fawn home ranges became more homogeneous and contained larger patches with less edge and fewer cover types, predation risk increased. These findings are consistent with similar work in the midwestern United States, despite landscape differences between regions. The combined weight of evidence suggests maintenance of a heterogeneous landscape consisting of relatively small dispersed patches may reduce fawn losses to coyotes. This information may also be used to identify areas susceptible to greater fawn predation rates across large spatial scales. However, the relatively long forestry rotation lengths and large scale of consistent forest management on the SRS are uncommon in the southeastern United States and the mechanism for the pattern we observed is unclear. Therefore, our results may not be applicable to sites with different forest management practices. © 2017 The Wildlife Society. Using forest management practices to create a heterogeneous landscape consisting of relatively small, dispersed patches may reduce coyote predation risk for white‐tailed deer fawns in the southeastern United States. We provide information that may be used to identify areas susceptible to greater predation rates of white‐tailed deer fawns by coyotes throughout the region.

Camera surveys commonly are used by managers and hunters to estimate white-tailed deer Odocoileus virginianusdensity and demographic rates. Though studies have documented biases and inaccuracies in the camera survey methodology, camera traps remain popular due to ease of use, cost-effectiveness, and ability to survey large areas. Because recruitment is a key parameter in ungulate population dynamics, there is a growing need to test the effectiveness of camera surveys for assessing fawn recruitment. At Savannah River Site, South Carolina, we used six years of camera-based recruitment estimates (i.e. fawn:doe ratio) to predict concurrently collected annual radiotag-based survival estimates. The coefficient of determination (R2) was 0.445, indicating some support for the viability of cameras to reflect recruitment. We added two years of data from Fort Bragg Military Installation, North Carolina, which improved R2to 0.621 without accounting for site-specific variability. Also, we evaluated the correlation between year-to-year changes in recruitment and survival using the Savannah River Site data; R2was 0.758, suggesting that camera-based recruitment could be useful as an indicator of the trend in survival. Because so few researchers concurrently estimate survival and camera-based recruitment, examining this relationship at larger spatial scales while controlling for numerous confounding variables remains difficult. Future research should test the validity of our results from other areas with varying deer and camera densities, as site (e.g. presence of feral pigs Sus scrofa) and demographic (e.g. fawn age at time of camera survey) parameters may have a large influence on detectability. Until such biases are fully quantified, we urge researchers and managers to use caution when advocating the use of camera-based recruitment estimates.

ABSTRACT Recent evidence from the southeastern United States of high predation rates by coyotes ( Canis latrans) on white-tailed deer ( Odocoileus virginianus) fawns combined with reports of predation on adult female deer have prompted concern among wildlife managers and hunters regarding the effects on deer populations. We examined survival rates and causes of mortality among 138 radiocollared adult female deer over 7 years at the Savannah River Site (SRS) in South Carolina, USA, 2006-2013. Our model-averaged prediction of annual survival was 0.871 (95% CI = 0.839-0.902) and did not vary among years. The best model describing survival patterns included only month, with survival being lowest during November-December, which coincided with hunting season. Models assessing the effects of harvest and distance from a primary road also received support (ΔAICc < 2.0), but effects of these variables were weak. Although harvest rates were low, harvest was the most frequent cause of mortality (13 of 30; 43%), followed by deer-vehicle collision (8 of 30; 27%). We did not detect predation as a cause of death among our sample; although cause of death for 7 (23%) mortalities was unknown. Even if all unknown mortalities were caused by predation, the overall effect of these mortalities on annual survival was low. Therefore, we conclude that predation by coyotes on adult females was not important in the SRS deer population demography. Managers of southern deer populations wishing to increase population growth by limiting antlerless harvest should be aware that adult female survival may already be high, so limited increases in survival may be expected, particularly if antlerless harvest already is limited. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Recent localized declines in white-tailed deer (Odocoileus virginianus) populations in the southeastern United States have been linked to increasing predation pressure from coyotes (Canis latrans), a novel predator to the region. Studies have documented coyotes as the leading cause of mortality for neonates, and 1 study documented coyotes as a mortality factor for adult females. However, no study has used field-based vital rates to conduct sensitivity analyses or model deer population trajectories under potential harvest or predator removal strategies. We used low, medium, and high values of fawn survival, adult female survival, and fecundity data collected from Fort Bragg Military Installation, North Carolina to demonstrate the current declining population trajectory for deer (??=?0.905; low ??=?0.788, high ??=?1.003). Consistent with other studies of ungulates, we determined adult female survival was the most sensitive and elastic vital rate. Further, for 3 potential management (“what if”) scenarios, we projected the population for 10 years using estimated vital rates. Reducing adult female harvest (??=?0.935; low ??=?0.875, high ??=?1.002) and coyote removal (??=?0.995; low ??=?0.898, high ??=?1.081) reduced the current population decline, whereas combining both approaches (??=?1.024; low ??=?0.898, high ??=?1.141) resulted in population increases. Our data indicate that for low-density deer populations with heavy predation pressure on neonates, protecting adult females from harvest may not completely offset population declines. Coyote removal might be a necessary strategy because it could possibly increase very low fawn survival, which appears to be the most important vital rate influencing ? in our study. However, managers may have to start with reductions in adult female harvest because coyote removal would have to be continuous and consistently effective, making it an impractical management approach by itself. © 2015 The Wildlife Society.

Predation by coyotes (Canis latrans) on white-tailed deer (Odocoileus virginianus) neonates has led to reduced recruitment in many deer populations in southeastern North America. This low recruitment combined with liberal antlerless deer harvest has resulted in declines in some deer populations, and consequently, increased interest in coyote population control. We investigated whether neonate survival increased after coyote removal, whether coyote predation on neonates was additive to other mortality sources, and whether understory vegetation density affected neonate survival. We monitored neonate survival for 4 years prior to (2006–2009) and 3 years during (2010–2012) intensive coyote removal on 3 32-km2units on the United States Department of Energy's Savannah River Site, South Carolina. We removed 474 coyotes (1.63?coyotes/km2per unit per year), reducing coyote abundance by 78% from pre-removal levels. The best model (wi?=?0.927) describing survival probability among 216 radio-collared neonates included a within-year quadratic time trend variable, date of birth, removal treatment, and a varying removal year effect. Under this model, survival differed between pre-treatment and removal periods and it differed among years during the removal period, being >100% greater than pre-treatment survival (0.228) during the first removal year (0.513), similar to pre-treatment survival during the second removal year (0.202), and intermediate during the third removal year (0.431). Despite an initial increase, the overall effect of coyote removal on neonate survival was modest. Mortality rate attributable to coyote predation was lowest during the first removal year (0.357) when survival was greatest, but the mortality rate from all other causes did not differ between the pre-treatment period and any year during removals, indicating that coyote predation acted as an additive source of mortality. Survival probability was not related to vegetation cover, either directly or in interaction with coyote abundance. When the objective is to increase the recruitment of white-tailed deer, we conclude that neither coyote control nor vegetation management appear effective. Reduction of the antlerless harvest may be necessary to meet this objective, but this harvest strategy warrants additional research in Southeastern deer populations. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Relationships between foraging habitat and reproductive success provide compelling evidence of the contribution of specific vegetative features to foraging habitat quality, a potentially limiting factor for many animal populations. For example, foraging habitat quality likely will gain importance in the recovery of the threatened red-cockaded woodpecker Picoides borealis(RCW) in the USA as immediate nesting constraints are mitigated. Several researchers have characterized resource selection by foraging RCWs, but emerging research linking reproductive success (e.g. clutch size, nestling and fledgling production, and group size) and foraging habitat features has yet to be synthesized. Therefore, we reviewed peer-refereed scientific literature and technical resources (e.g. books, symposia proceedings, and technical reports) that examined RCW foraging ecology, foraging habitat, or demography to evaluate evidence for effects of the key foraging habitat features described in the species' recovery plan on group reproductive success. Fitness-based habitat models suggest foraging habitat with low to intermediate pine Pinusspp. densities, presence of large and old pines, minimal midstory development, and herbaceous groundcover support more productive RCW groups. However, the relationships between some foraging habitat features and RCW reproductive success are not well supported by empirical data. In addition, few regression models account for > 30% of variation in reproductive success, and unstandardized multiple and simple linear regression coefficient estimates typically range from -0.100 to 0.100, suggesting ancillary variables and perhaps indirect mechanisms influence reproductive success. These findings suggest additional research is needed to address uncertainty in relationships between foraging habitat features and RCW reproductive success and in the mechanisms underlying those relationships.

Coyotes (Canis latrans) are novel predators throughout the southeastern United States and their depredation of white-tailed deer (Odocoileus virginianus) neonates may explain observed declines in some deer populations in the region, but direct evidence for such a relationship is lacking. Our objective was to quantify neonate survival rates and causes of mortality at the United States Department of Energy's Savannah River Site (SRS), South Carolina to directly evaluate degree of predation in this deer population. From 2006 to 2009, we radio-monitored 91 neonates captured with the aid of vaginal implant transmitters in pregnant adult females and opportunistic searches. Overall Kaplan–Meier survival rate to 16 weeks of age was 0.230 (95% CI?=?0.155–0.328), and it varied little among years. Our best-fitting model estimated survival at 0.220 (95% CI?=?0.144–0.320). This model included a quadratic time trend variable (lowest survival rate during the first week of life and increasing to near 1.000 around week 10), and Julian date of birth (survival probability declining as date of birth increased). Predation by coyotes was the most frequent cause of death among the 70 monitored neonates that died, definitively accounting for 37% of all mortalities and potentially accounting for as much as 80% when also including probable coyote predation. Predation by bobcats (Felis rufus) accounted for 7% (definitive) to 9% (including probable bobcat predation) of mortalities. The level of coyote-induced mortality we observed is consistent with the low recruitment rates exhibited in the SRS deer population since establishment of coyotes at the site. If representative of recruitment rates across South Carolina, current harvest levels appear unsustainable. This understanding is consistent with the recent declining trend in the statewide deer population. The effects of coyote predation on recruitment should be considered when setting harvest goals, regardless of whether local deer population size is currently above or below desired levels, because coyotes can substantially reduce fawn recruitment. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

Red-headed woodpecker (Melanerpes erythrocephalus) populations have declined in the United States and Canada over the past 40?years. However, few demographic studies have been published on the species and none have addressed adult survival. During 2006–2007, we estimated survival probabilities of 80 radio-tagged red-headed woodpeckers during the breeding season in mature loblolly pine (Pinus taeda) forests in South Carolina. We used known-fate models in Program MARK to estimate survival within and between years and to evaluate the effects of foliar cover (number of available cover patches), snag density treatment (high density vs. low density), and sex and age of woodpeckers. Weekly survival probabilities followed a quadratic time trend, being lowest during mid-summer, which coincided with the late nestling and fledgling period. Avian predation, particularly by Cooper's (Accipiter cooperii) and sharp-shinned hawks (A. striatus), accounted for 85% of all mortalities. Our best-supported model estimated an 18-week breeding season survival probability of 0.72 (95% CI?=?0.54–0.85) and indicated that the number of cover patches interacted with sex of woodpeckers to affect survival; females with few available cover patches had a lower probability of survival than either males or females with more cover patches. At the median number of cover patches available (n?=?6), breeding season survival of females was 0.82 (95% CI?=?0.54–0.94) and of males was 0.60 (95% CI?=?0.42–0.76). The number of cover patches available to woodpeckers appeared in all 3 of our top models predicting weekly survival, providing further evidence that woodpecker survival was positively associated with availability of cover. Woodpecker survival was not associated with snag density. Our results suggest that protection of =0.7 cover patches per ha during vegetation control activities in mature pine forests will benefit survival of this Partners In Flight Watch List species. © 2011 The Wildlife Society.

ABSTRACT The coyote (Canis latrans) is a recent addition to the fauna of eastern North America, and in many areas coyote populations have been established for only a decade or two. Although coyotes are known predators of white-tailed deer (Odocoileus virginianus) in their historic range, effects this new predator may have on eastern deer populations have received little attention. We speculated that in the southeastern United States, coyotes may be affecting deer recruitment, and we present 5 lines of evidence that suggest this possibility. First, the statewide deer population in South Carolina has declined coincident with the establishment and increase in the coyote population. Second, data sets from the Savannah River Site (SRS) in South Carolina indicate a new mortality source affecting the deer population concurrent with the increase in coyotes. Third, an index of deer recruitment at SRS declined during the period of increase in coyotes. Fourth, food habits data from SRS indicate that fawns are an important food item for coyotes during summer. Finally, recent research from Alabama documented significant coyote predation on fawns there. Although this evidence does not establish cause and effect between coyotes and observed declines in deer recruitment, we argue that additional research should proactively address this topic in the region. We identified several important questions on the nature of the deer—coyote relationship in the East.

AbstractDuring 2001, we used active acoustical sampling (Anabat II) to survey foraging habitat relationships of bats on the Savannah River Site (SRS) in the upper Coastal Plain of South Carolina. Using an a priori information-theoretic approach, we conducted logistic regression analysis to examine presence of individual bat species relative to a suite of microhabitat, stand, and landscape-level features such as forest structural metrics, forest type, proximityto riparian zones and Carolina baywetlands, insect abundance, and weather. There was considerable empirical support to suggest that the majority of the activity of bats across most of the 6 species occurred at smaller, stand-level habitat scales that combine measures of habitat clutter (e.g., declining forest canopy cover and basal area), proximity to riparian zones, and insect abundance. Accordingly, we hypothesized that most foraging habitat relationships were more local than landscape across this relatively large area for generalist species of bats. The southeastern myotis (Myotis austroriparius) was the partial exception, as its presence was linked to proximity of Carolina bays (best-approximating model) and bottomland hardwood communities (other models with empirical support). Efforts at SRS to promote open longleaf pine (Pinus palustris) and loblolly pine (P. taeda) savanna conditions and to actively restore degraded Carolina bay wetlands will be beneficial to bats. Accordingly, our results should provide managers better insight for crafting guidelines for bat habitat conservation that could be linked to widely accepted land management and environmental restoration practices for the region.

Abstract: Social behavior of white-tailed deer (Odocoileus virginianus) can have important management implications. The formation of matrilineal social groups among female deer has been documented and management strategies have been proposed based on this well-developed social structure. Using radiocollared (n= 17) and hunter or vehicle-killed (n= 21) does, we examined spatial and genetic structure in white-tailed deer on a 7,000-ha portion of the Savannah River Site in the upper Coastal Plain of South Carolina, USA. We used 14 microsatellite DNA loci to calculate pairwise relatedness among individual deer and to assign doe pairs to putative relationship categories. Linear distance and genetic relatedness were weakly correlated (r= -0.08, P= 0.058). Relationship categories differed in mean spatial distance, but only 60% of first-degree-related doe pairs (full sibling or mother-offspring pairs) and 38% of second-degree-related doe pairs (half sibling, grandmother-granddaughter pairs) were members of the same social group based on spatial association. Heavy hunting pressure in this population has created a young age structure among does, where the average age is <2.5 years, and <4% of does are >4.5 years old. This—combined with potentially elevated dispersal among young does—could limit the formation of persistent, cohesive social groups. Our results question the universal applicability of recently proposed models of spatial and genetic structuring in white-tailed deer, particularly in areas with differing harvest histories.

Abstract: We compared bat activity levels in the Coastal Plain of South Carolina among 5 habitat types: forested riparian areas, clearcuts, young pine plantations, mature pine plantations, and pine savannas. We used time-expansion radio-microphones and integrated detectors to simultaneously monitor bat activity at 3 heights (30, 10, 2 m) in each habitat type. Variation in vegetative clutter among sampling heights and among habitat types allowed us to examine the differential effect of forest vegetation on the spatial activity patterns of clutter-adapted and open-adapted bat species. Moreover, monitoring activity at 30, 10, and 2 m permitted us to also compare bat activity above and below the forest canopy. We detected calls of 5 species or species groups: eastern red/Seminole bats (Lasiurus borealis/L. seminolus), eastern pipistrelles (Pipistrellus subflavus), evening bats (Nycticeius humeralis), big brown bats (Eptesicus fuscus), and hoary bats (Lasiurus cinerius). At 2 and 10 m, bat activity was concentrated in riparian areas, whereas we detected relatively low levels of bat activity in upland habitats at those heights. Activity was more evenly distributed across the landscape at 30 m. Bat activity levels above the forest canopy were almost 3 times greater than within or below the canopy. We detected significantly greater activity levels of 2 open-adapted species (hoary and big brown bats) above rather than within or below the forest canopy. However, activity levels of 2 clutter-adapted species (eastern red/Seminole bats and eastern pipistrelles) did not differ above, within, or below the forest canopy. Despite classification as a clutter-adapted species, evening bat activity was greater above rather than within or below the forest canopy. We believe our results highlight the importance of riparian areas as foraging habitat for bats in pine-dominated landscapes in the southeastern United States. Although acoustical surveys conducted below forest canopies can provide useful information about species composition and relative activity levels of bats that forage in cluttered environments, our results showing activity above canopy suggest that such data may not accurately reflect relative activity of bats adapted to forage in more open conditions, and therefore may provide an inaccurate picture of bat community assemblage and foraging habitat use.

Knowledge of directional tendencies among long-distance movements by animals can be important in planning conservation and management strategies for wildlife at the landscape scale. The direction of 23 long-distance movements (=2 km) among a non-migratory population of white-tailed deer Odocoileus virginianuson the Osceola National Forest, Florida, during 1989–1991 was examined. Direction of dispersal by 10 yearlings (7 males, 3 females) was non-uniform in distribution and averaged 95°. Direction of 13 excursions by 12 adults (2 males, 10 females) also was non-uniform but was bimodally (east-west) distributed; mean directions of the two distributions were 83° and 261°. Thus, both excursions and dispersals of radio-instrumented deer were on an east-west axis. No prominent landscape features that would direct deer movement were apparent. However, the fact that deer movements followed a consistent directional trend, even in a relatively homogeneous landscape, may have important implications for management of gene flow among small populations.

Shrew abundance has been linked to the presence of coarse woody debris (CWD), especially downed logs, in many regions in the United States. We investigated the importance of CWD to shrew communities in managed upland pine stands in the southeastern United States Coastal Plain. Using a randomized complete block design, 1 of the following treatments was assigned to twelve 9.3-ha plots: removal (n = 3; all downed CWD =10 cm in diameter and =60 cm long removed), downed (n = 3; 5-fold increase in volume of downed CWD), snag (n = 3; 10-fold increase in volume of standing dead CWD), and control (n = 3; unmanipulated). Shrews (Blarina carolinensis, Sorex longirostris, and Cryptotis parva) were captured over 7 seasons from January 2007 to August 2008 using drift-fence pitfall trapping arrays within treatment plots. Topographic variables were measured and included as treatment covariates. More captures of B. carolinensis were made in the downed treatment compared to removal, and captures of S. longirostris were greater in downed and snag compared to removal. Captures of C. parva did not differ among treatments. Captures of S. longirostris were positively correlated with slope. Our results suggest that abundance of 2 of the 3 common shrew species of the southeastern Coastal Plain examined in our study is influenced by the presence of CWD.

Malaise and pitfall traps were used to sample herbivorous insects in canopy gaps created by group-selection cutting in a bottomland hardwood forest in South Carolina. The traps were placed at the centers, edges, and in the forest adjacent to gaps of different sizes (0.13, 0.26, and 0.50 ha) and ages (1 and 7 yr old) during four sampling periods in 2001. Overall, the abundance and species richness of insect herbivores were greater at the centers of young gaps than at the edge of young gaps or in the forest surrounding young gaps. There were no differences in abundance or species richness among old gap locations (i.e., centers, edges, and forest), and we collected significantly more insects in young gaps than old gaps. The insect communities in old gaps were more similar to the forests surrounding them than young gap communities were to their respective forest locations, but the insect communities in the two forests locations (surrounding young and old gaps) had the highest percent similarity of all. Although both abundance and richness increased in the centers of young gaps with increasing gap size, these differences were not significant. We attribute the increased numbers of herbivorous insects to the greater abundance of herbaceous plants available in young gaps.

Individual identification of animals from camera traps has become an important task in wildlife research, but camera deployment methods often do not facilitate this important undertaking. Identification of individual golden eagles (Aquila chrysaetos) is possible using uniquely marked rectrices, but no studies have explored methods to maximize the rate of individual identification from camera images. Our objectives were to assess whether different camera heights (1 m vs. 3 m), image capture settings (one image after a 1‐min delay vs. burst of 5 images after a 30 sec delay), and arrangements relative to bait (dorsally vs. ventrally aimed) affected views of rectrices on golden eagles and our ability to identify individuals. We conducted our study from 15 December 2016 to 3 March 2017 on the Savannah River Site, South Carolina. First, we developed a scoring system based on views of rectrices and used a linear mixed‐effects model to compare image scores among different camera arrangements and image settings. Next, after identifying individual eagles, we used generalized linear mixed‐effects models to compare total individual eagle detections, total days an individual was detected, and probability of obtaining an unknown individual identification among camera arrangements and settings. Overall, we scored a total of 27,499 images, with 8,083 providing views of marked rectrices that allowed identification of 18 individual eagles. Average image scores and proportion of images suitable for individual identification were higher from elevated (3 m) camera arrangements than standard arrangements (1 m) across sites. Regardless of camera height, faster frequency of image capture provided more images that could be used to identify individuals and the most trap days per individual. Researchers and managers should consider deploying elevated cameras traps with faster frequency of image capture to improve data quality and potential for analysis of golden eagle populations and trends across the species' range. Published 2021. This article is a U.S. Government work and is in the public domain in the USA. : Elevated cameras using faster image capture settings can provide better and more images of unique golden eagle (Aquila chrysaetos) rectrices, regardless of bait positions and motion sensor idiosyncrasies. Researchers and managers should consider deploying elevated remote cameras with faster frequency of image capture to maximize rate of individual identification when monitoring golden eagle populations and trends across the species' range. [ABSTRACT FROM AUTHOR]