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Abstract Obtaining rigorous baseline density estimates of species of conservation interest is key when assisting landowners to achieve management goals on private lands. Northern bobwhite (Colinus virginianus) populations are declining throughout their range and despite being the focus of numerous private land conservation initiatives, baseline density estimates in privately owned pine forests are lacking. We sought to address this knowledge gap across the Southeastern United States by sampling 105 privately owned pine stands throughout 2018 to 2020 using observer point count and autonomous recording unit (ARU) sampling data. Using Bayesian hierarchical models, we investigated the influence of stand management (brush management or applied fire) on bobwhite density, as well as four landscape‐scale environmental variables. These included percentage cover of forest, herbaceous, agricultural or burnt land area across six different spatial scales ranging from 500‐m to 10‐km around each pine stand. Baseline density on sites with no management was estimated to be 2.24 coveys per 100 ha (1.00–5.03, 95% BCI), with little impact of applying brush management, but a trend for a positive effect of fire management (0.19, −0.01 to 0.38 95% BCI). This impact of fire was seen at both the stand‐scale, correlated with an increase in acreage of applied prescribed burn management, and across the greater landscape area, correlated with cover of burnt area within a 2‐km buffer around each site. There were also strong positive influences of herbaceous vegetation and a strong negative influence of forest cover on bobwhite density. Practical implication: our sampling efforts fill an important information gap regarding densities throughout private lands in the Southeastern United States. Our study also highlights the necessity of landscape scale planning for Northern Bobwhite conservation initiatives because the efficacy of conservation practices (i.e. prescribed fire and brush management) could be altered by the landscape surrounding the treated forest stand.

Abstract Passive acoustic monitoring using Autonomous Recording Units (ARUs) is becoming a significant research tool for collecting large amounts of ecological data. Northern bobwhite Colinus virginianus is an economically important game bird whose declining populations are of conservation concern, so efforts to monitor bobwhite abundance using ARUs are being intensified. Yet, manual processing of ARU data is time consuming and often expensive, so developing automatic call detection methods is a key step in acoustic monitoring. We present here the first single species convolutional neural network (CNN) developed purely for automatic bobwhite covey call identification and classification. We demonstrate the value of meaningful data augmentation by including non‐target calls and background noise into our training dataset, as well as evaluating alternative CNN score thresholds and model extrapolation performance. We trained our CNN on 6,682 manually labeled covey calls across three groups of sites within the southeastern USA. Precision and AUC from both CNN classification and individual call detection was high (0.80–0.99), and our model showed strong extrapolation ability across site groups. However, extrapolation performance significantly decreased for sites that were more dissimilar to the training data set if our meaningful data augmentation process was omitted. Our CNN detected significantly more covey calls than manual labeling using Raven Pro software, and processing time was greatly reduced: a single one hour wav file can be now analyzed by the CNN in roughly eight seconds. We also demonstrate using a simple case study that extremely high variability in estimates of bobwhite site occupancy and detection are obtained depending on the method of acoustic data processing (manual versus CNN). Our results suggest that our CNN provides robust and time‐saving analysis of bobwhite covey call acoustic data and can be applied to future research and monitoring projects with high confidence in the performance of the model.

Abstract Private landowners who operate multifunctional landscapes play a critical role in the conservation of native and imperiled species, and the restoration of native ecosystems. In the southeastern United States, both northern bobwhite (Colinus virginianus) and pine savanna ecosystems are imperiled and heavily reliant on conservation efforts by private landowners. Engaging private landowners in the restoration and management of pine savannas and grasslands is essential to the recovery of northern bobwhite, which is also managed as a game species. Since the early 1900s, the cultural tradition of wild bobwhite hunting has motivated landowners to manage their properties to increase bobwhite populations. However, the costs and revenues associated with intensive wild bobwhite management and hunting are imperfectly understood. From May 2021 to February 2022, we conducted semistructured interviews with landowners and land managers of 37 wild bobwhite hunting properties (total of 65,317 ha in bobwhite management) in Alabama, Georgia, Florida, and South Carolina to enumerate the costs and revenues associated with intensive wild bobwhite management. Landowners spent an average of $154/acre/year (~$381/ha/year; median of $142/acre/year or ~$352/ha/year) to manage for northern bobwhite. These costs included salaries and benefits for labor, depreciated equipment and infrastructure expenditures, and other supplies (e.g., fuel, seed) needed to maintain wild bobwhite populations and their habitat. Few properties offset their bobwhite management costs with revenues generated on the property, including hunting revenues. Non‐financial motivations for owning a bobwhite property included a strong land stewardship ethic, the desire to maintain rural lifestyles and family heritage, and securing hunting and recreational opportunities. Through wild quail management, private landowners are helping to secure critical habitat for threatened and endangered species and increasing the landscape's overall resilience to climate change without the use of public funding.

Abstract Sericea lespedeza (Lespedeza cuneata) is an invasive nonnative legume that commonly occurs on sites managed for northern bobwhite (Colinus virginianus). Sericea reduces bobwhite habitat availability by outcompeting native plants that provide food and cover. Sericea can be controlled with postemergence herbicides such as glyphosate as well as a mixture of triclopyr with fluroxypyr, but these herbicides do not provide preemergence control. Imazapic has been effective at controlling a limited number of planted sericea seeds, but the efficacy of imazapic at various application rates to control sericea seedbank response following treatment with a postemergence herbicide has not been evaluated. We designed a field experiment to evaluate sericea control and changes in the plant community as related to bobwhite habitat with 2 postemergence herbicides followed by preemergence treatment of imazapic at 3 sites in Tennessee and Alabama, USA, 2018–2022. Specifically, we treated sericea with postemergence broadcast applications of glyphosate or triclopyr with fluroxypyr in 2018 and applied spot treatment with the same herbicides in 2019–2021. We applied imazapic at 4 rates following prescribed fire in 2019 and 2022. We measured coverage of sericea, native forbs, annual grasses, perennial grasses, and bobwhite food plants before treatment in 2018 and after all treatments in 2022. Nearly all postemergence treatments reduced sericea coverage, but imazapic did not increase control compared to postemergence herbicides alone. Perennial grasses used for nesting and bobwhite foraging were maintained following treatments. We recommend managers use either glyphosate or triclopyr with fluroxypyr to control sericea postemergence and consider using a low rate of imazapic to reduce annual grasses if coverage is a problem on the site.

Abstract Predators can significantly limit the amount of available habitat for vulnerable prey. Encouraging spatial segregation of predators and prey through habitat management prescriptions may be a useful tool to increase productivity and abundances of prey species of conservation concern. We estimated the total area of low‐risk nesting habitat by interacting predator habitat selection models with northern bobwhite (Colinus virginianus) nest‐site selection models. We used trail cameras, transect sampling, spotlighting transects, and incidental tracking to survey and map occurrences of mesopredators at a site in western Oklahoma, USA. We created broad‐scale resource selection function models for bobwhite nest‐site and mesopredator habitat selection using generalized linear models to create maps of occurrence probability in ArcGIS. Bobwhite nests were more likely to be depredated in areas of high selection by coyotes (Canis latrans) and striped skunks (Mephitis mephitis) compared to areas with low mesopredator selection. Approximately 392 ha of bobwhite nesting habitat (17%) had low probabilities of selection by both coyotes and striped skunks. Our results demonstrate the need for incorporating species' interactions into estimations of available habitat. Based on the total area of highly selected cover by northern bobwhite, approximately 29% of the study area would have been deemed suitable for nesting. However, only 5% of that area is predicted to have a low predation risk.

Abstract Climate change is predicted to increase the intensity and frequency of weather extremes (e.g., extreme heat and drought), which will likely affect wildlife species in significant ways. Maintaining landscape heterogeneity has been suggested as a potential conservation strategy to buffer animals from weather extremes. Because animal movement influences survival and population connectivity, understanding animal space use and movement in response to shifts in weather is useful for the conservation of wildlife. Nonmigratory species are predicted to be more negatively affected by climate change because they have a limited ability to disperse to find resources. We studied the Northern Bobwhite (Colinus virginianus; hereafter, bobwhite) to understand how weather alters habitat use and movement of a nonmigratory animal across a landscape. We collected telemetry locations on bobwhite across western Oklahoma during 2019–2020 and paired these data with meteorological and vegetation data. We analyzed the data at two temporal scales—hourly locations and 12‐h paths. At the hourly scale, we analyzed tree cover use, shrub cover use, and normalized difference vegetation index (NDVI) use using generalized or linear‐mixed models. At the 12‐h scale, we calculated three different movement metrics: cumulative distance, net displacement, sinuosity and analyzed each movement metric separately using generalized linear‐mixed models. We found that bobwhite used denser tree cover and higher NDVI values as air temperature increased in conjunction with solar radiation. Bobwhite used denser shrub cover as air temperature increased and average wind speed was high as well as when air temperature and average wind speed were low. The interaction between variability in vegetation and climate influenced bobwhite movement. Bobwhite in areas with higher NDVI variance moved farther when mean air temperatures were >0°C than bobwhite in areas with low NDVI variance. When mean air temperatures were ≤0°C, NDVI variance had little effect on the cumulative distance moved of bobwhite. Our findings show that some animals use different vegetation types during different weather conditions and that variability in vegetation on the landscape and weather together alters animal movement. Managing for landscape heterogeneity is a solution that may buffer animals from increased climate variability in the future.

ABSTRACT Reliable and unbiased information is needed for informing management decisions relevant to all animal life stages. Radiomarking is commonly used for adult birds, but this approach is more challenging for galliform chicks. Following preliminary experimentation of multiple attachment methods, we selected 2 radiotransmitter attachment techniques, gluing and suturing, to test on 11‐day‐old northern bobwhite (Colinus virginianus; hereafter, bobwhite) chicks in an outdoor aviary environment during 1 May 2013 through 30 Sep 2016. In addition, we field‐tested a novel, modified‐suture technique on 11‐ and 12‐day‐old wild bobwhite chicks. We found that suturing was a superior method of transmitter attachment. Glue‐on attachment of transmitters performed poorly with average retention rates

ABSTRACT Capturing animals is a critical component of many ecological research projects. Factors that increase capture success can save time, money, and improve inference. Even though northern bobwhites (Colinus virginianus) are intensively studied, little information exists on factors that influence trapping success. Using baited walk‐in funnel traps during 2019, we examined how putting cover over traps, scraping litter and vegetation under traps, distance to nearest cover, overhead cover, date, time, and weather influenced trapping success of northern bobwhites in northeastern Colorado, USA. We found that cover placed over traps, litter scraped away underneath traps, traps placed closer to cover, and windy days resulted in greater trapping success. These results should enable researchers to be more successful capturing bobwhites and result in larger samples and more precise inference in future studies. © 2020 The Wildlife Society.

ABSTRACT Reliable methods for monitoring wildlife populations are paramount to effective conservation and management. There are a variety of available techniques that vary in cost and feasibility. We field‐tested a commercially available acoustic recording device (ARD) in July and August of 2018 with the goal of standardizing the process of surveying northern bobwhite (Colinus virginianus) populations using acoustic data. We projected bobwhite covey calls from programmable speakers, and analyzed recordings manually and with automatic recognition software. We manually detected 48% of projected covey calls with the furthest detection at 241 m. We developed an automatic classifier using Kaleidoscope Pro (Wildlife Acoustics Inc.), which detected 31% of the manually detected covey calls. The automatic classifier was ineffective, so we used manual analysis to acquire measurements for call strength and background noise at each visible covey call spectrogram signature. Detection probability declined as distance from the ARD increased and background noise increased. However, in our study system, there was no effect of vegetation structure on detection probability. Our results provide a blueprint for evaluating ARDs for application to wildlife monitoring. We believe ARDs can be used to evaluate northern bobwhite occupancy at fine scales and may potentially be useful in estimating autumn densities for setting harvest regulations. We encourage the evaluation of other software recognition programs and the relationship between covey call detection and landscape structure. © 2020 The Wildlife Society.

Abstract Global climate change is causing increased climate extremes threatening biodiversity and altering ecosystems. Climate is comprised of many variables including air temperature, barometric pressure, solar radiation, wind, relative humidity, and precipitation that interact with each other. As movement connects various aspects of an animal's life, understanding how climate influences movement at a fine‐temporal scale will be critical to the long‐term conservation of species impacted by climate change. The sedentary nature of non‐migratory species could increase some species risk of extirpation caused by climate change. We used Northern Bobwhite (Colinus virginianus; hereafter bobwhite) as a model to better understand the relationship between climate and the movement ecology of a non‐migratory species at a fine‐temporal scale. We collected movement data on bobwhite from across western Oklahoma during 2019–2020 and paired these data with meteorological data. We analyzed movement in three different ways (probability of movement, hourly distance moved, and sinuosity) using two calculated movement metrics: hourly movement (displacement between two consecutive fixes an hour apart) and sinuosity (a form of tortuosity that determines the amount of curvature of a random search path). We used generalized linear‐mixed models to analyze probability of movement and hourly distance moved, and used linear‐mixed models to analyze sinuosity. The interaction between air temperature and solar radiation affected probability of movement and hourly distance moved. Bobwhite movement increased as air temperature increased beyond 10°C during low solar radiation. During medium and high solar radiation, bobwhite moved farther as air temperature increased until 25–30°C when hourly distance moved plateaued. Bobwhite sinuosity increased as solar radiation increased. Our results show that specific climate variables alter the fine‐scale movement of a non‐migratory species. Understanding the link between climate and movement is important to determining how climate change may impact a species’ space use and fitness now and in the future.

Abstract Increased variation in interannual weather due to climate change can exert a powerful influence on the population dynamics of a species. Understanding the influence of severe weather is important for managing weather‐sensitive species. While best management practices target vital rates that are affected by weather, focusing on a single vital rate may not be sufficient if other vital rates are secondarily limiting. A comprehensive modeling framework to forecast future population dynamics while incorporating weather scenarios and vital rate variation within observed ranges that can be affected by management actions are necessary. A potential approach is to combine an integrated population model (IPM) with a population viability analysis (PVA) to generate novel insights about population dynamics. We used the northern bobwhite (Colinus virginianus), a rapidly declining gamebird sensitive to snowfall along the northern extents of the species' range, to demonstrate the utility of a coupled IPM‐PVA framework for projecting the response of a population to weather, management, and changes in vital rates. We created an IPM using two sources of count data spanning seven years, five years of winter survival data, and two years of breeding season demographics for a declining bobwhite population in southwestern Ohio during 2007–2015. Quasi‐extinction probability at the end of the decadal projection during 2019–2029 was 0.384–0.410 for mild, average, and severe winter weather scenarios. Quasi‐extinction probability declined to 0.326 with 20% improvement in nest success and summer survival rates. A concurrent 20% increase in winter survival further reduced quasi‐extinction probability to 0.263, which is a ˜36% reduction in quasi‐extinction probability compared with the baseline scenario with no changes in vital rates. These results suggest that long‐term viability of this population may depend on extensive management of winter habitat to improve survival but will also require management actions to improve fecundity after severe winters. Our modeling approach demonstrated how IPMs can be used to project population responses to future weather conditions and overcome some of the pitfalls of traditional PVA. The coupled framework presented here can serve as a tool for managers to make climate‐informed management decisions.

ABSTRACT Landscape‐scale conservation initiatives have become more common in the past few decades. Many factors led to these increases including a broadening of conservation strategies, technology, and threats to many ecological systems; species’ population declines; and a growing understanding of the need for cooperative conservation. Population and habitat threats and declines often occur on privately owned farms, ranches, and forests, sometimes referred to as ‘working lands,’ which presents a host of challenges and opportunities for conservation. A key challenge of emerging initiatives is funding for conservation. We explore 2 landscape‐scale initiatives that have become loosely linked by the Working Lands for Wildlife partnership. Both have benefited from U.S. Department of Agriculture (USDA) funding that resulted from an agreement between the USDA Natural Resources Conservation Service and the U.S. Department of Interior Fish and Wildlife Service (USDA 2012). We describe a few national cooperative conservation developments to demonstrate their importance to our 2 case studies and the ecosystem of private lands wildlife conservation. © 2019 The Wildlife Society.

Abstract Human hunting activity and disturbance can significantly impact prey species through both consumptive and nonconsumptive effects. The nonconsumptive effects of rabbit hunting on Northern Bobwhite (Colinus virginianus; hereafter, bobwhite) are currently unknown. Increased perceived risk of predation by bobwhite during rabbit hunting events may elicit antipredator responses among bobwhite that impact fitness via changes in behavior that ultimately impact population growth. We estimated the nonconsumptive effects of rabbit hunting on bobwhite behavior using telemetry across varying rabbit hunting intensities. Movements were analyzed using Bayesian hierarchical modeling with a before‐after‐control‐impact (BACI) design to determine the effect of rabbit hunting on bobwhite. We observed an overall reduction in bobwhite movement in the presence of rabbit hunting, with a 38% (Posterior Overlap = 0.01) increase in bobwhite step length in the absence of rabbit hunting. We also observed bobwhite maintaining closer proximity to hardwood and escape cover under high rabbit hunting intensity, with a 59% (Posterior Overlap = 0.03) increase in distance from hardwood and a 28% (Posterior Overlap = 0.14) increase in distance from escape cover when rabbit hunting was removed. Synthesis and applications. Heightened antipredator behavior through decreased movement may assist with bobwhite predator avoidance. However, decreased movement and increased use of poor habitats may also have negative effects as a result of reduced foraging time or increased susceptibility to other predators. Future research should attempt to quantify the effect of decreased movement on bobwhite fitness through the evaluation of foraging time and survival in order to continue to improve management efforts for the species.

ABSTRACT Northern bobwhite (Colinus virginianus) abundance has declined range‐wide over the long term due to factors such as habitat loss and deterioration. Private land management is critical to bobwhite conservation because most bobwhites occur on private lands, but little research has been conducted regarding how private land managers and landowners make decisions about whether and how to restore northern bobwhite habitat. To begin addressing this deficit, we used a choice‐based conjoint approach to determine how Texas, USA, landowners and land managers (surveyed in November 2017) weigh the importance of northern bobwhite hunting opportunities, costs, and labor when making habitat restoration decisions. We also used a latent class analysis to break respondents into segments based on their valuations of these attributes. The results of our latent class analysis indicate that managers and landowners can be grouped into several segments, and most segments do not place a high value on bobwhite hunting opportunities, but instead are more interested in minimizing out‐of‐pocket costs and labor input. Bobwhite habitat restoration programs yielding cost shares ≥50%, labor inputs at ≤30 days/year, and likely coveys flushed per hunting day >4 broadly appealed to landowners; however, ensuring low labor costs was most important, particularly for pragmatic landowners. This indicates that policies minimizing labor inputs and maximizing cost shares may be preferred over increasing hunting opportunities. Finally, we discuss the management preferences and practices of the segment most interested in maximizing bobwhite hunting opportunities and potential outreach strategies for segments of opportunistic and pragmatic landowners who may be persuaded to manage for bobwhite habitat if they perceived this management as economically viable. © 2019 The Authors. Wildlife Society Bulletin Published by Wiley Periodicals, Inc.

Abstract Humans modify landscapes for a variety of reasons including agriculture, urbanization, and to facilitate recreation. Landscape modifications can lead to complete loss of existing cover types and/or fragmentation of remaining cover types. Grasslands are one of the ecosystems most heavily impacted by human modifications; however, for many species, an understanding of how fragmentation affects population parameters is lacking. We investigated the influence of landscape fragmentation on survival, reproduction, and density using the northern bobwhite (Colinus virginianus), a facultative grassland species, as our case study. We experimentally manipulated the level of edge density (none, low, and high) of bobwhite management units and estimated seasonal survival, productivity, and autumn densities. Winter survival was lower in edge density treatments, relative to the control. An increase in migratory raptor density during the winter, along with a decrease in thermal refugia, may be contributing to lower winter survival in edge density treatments. Fecundity was higher in the edge density treatments, relative to the control, and was negatively related to winter survival. Similarly, breeding season survival was higher in more fragmented sites. This indicated a density‐dependent relationship, where lower bird densities at the beginning of the breeding season possibly led to greater resource availability, and thus survival and productivity, of the birds that remained. However, a density‐dependent response in breeding season survival and productivity was not enough to offset the negative impact of edges in the low edge density sites. Consequently, autumn density was lower relative to both control and high edge density treatments. Our study demonstrates the importance of capturing the entire life cycle when exploring the relationship between landscape pattern and population parameters.

ABSTRACT Northern bobwhite (Colinus virginianus) populations have been declining in Texas, USA, for nearly 3 decades. Reasons for the decline are unclear; however, a variety of factors have been considered, including pesticides and other environmental contaminants. We assessed potential effects of neonicotinoid insecticides on bobwhites by analyzing liver tissues from specimens collected in 3 selected regions of Texas. Fifty‐seven bobwhites were collected from the South Texas Plains, Rolling Plains, and Gulf Coast Prairies and Marshes regions during autumn 2014 and spring 2015. Neonicotinoid compounds were detected in trace amounts in the livers of 7 quail, including samples from all 3 field sites and during both collecting periods. Signs of testicular degeneration (n = 2) and hepatocellular vacuolation (n = 10) were consistent with known results of neonicotinoid intoxication. Overall, we identified evidence of bobwhite exposure to neonicotinoid insecticides, which correlates with a previous study that suggests that neonicotinoid use may be contributing to quail decline in some ecoregions in Texas, particularly the High Plains, Rolling Plains, Gulf Coast Prairies and Marshes, South Texas Plains, and Edwards Plateau. © 2018 The Wildlife Society.

ABSTRACT Encounter rates may have multifaceted effects on population dynamics, hunter satisfaction, and hunter retention. However, there is currently a lack of knowledge pertaining to those factors affecting small game flush rates. In an effort to address this paucity of information, we investigated factors that may affect flush rates of 3 small game species: ruffed grouse (Bonasa umbellus; hereafter, grouse), northern bobwhite (Colinus virginianus; hereafter, bobwhite), and rabbit (Sylvilagus spp.). From 2003 to 2015, we collected cooperator hunting logs for 3,948 grouse hunts, 19,301 rabbit hunts, and 4,798 bobwhite hunts in Kentucky, USA. Hunting success was defined as the number of grouse, rabbit, or bobwhite coveys flushed by a hunting party. We used an information theoretic approach to model variables that may explain variation in hunting success. The number of hunters within a party explained the greatest amount of variation in hunting success for all species, with a positive relationship between the number of hunters and success. Similarly, for grouse and rabbit, we observed a positive relationship between the number of dogs in a party and hunting success. Weather variables and annual abundance indices were not supported in any competing models explaining hunting success, suggesting a possible scale mismatch related to these broad‐scale data and more localized conditions experienced by hunting parties. Our research indicates that increasing hunting party size through the addition of hunters and dogs was a unifying influence on increasing hunting success (likely through increased hunting corridors) across small game species. This information can be useful for agencies seeking to increase or maintain support for small game hunters in the future. © 2018 The Wildlife Society.

ABSTRACT Relationships between northern bobwhite (Colinus virginianus) population dynamics and weather are well‐established and managed in the southern and western core of their range. Although a qualitative recognition of effects of winter weather at the northern edge of the northern bobwhite range exists, quantitative evaluations that examine impacts of severe winter weather events on declining northern populations are lacking. We used radiotelemetry to evaluate relationships between daily survival and winter weather in 2 northern populations in Maryland and Ohio, USA. Ninety‐day winter (Dec–Feb) survival varied with total snow accumulation among years and sites, with lowest survival (0.007, SE = 0.007) occurring during greatest snow accumulation and highest survival (0.498, SE = 0.088) during the mildest winter. Snow depths were negatively associated with daily survival in Ohio and Maryland, whereas association with temperature was marginal and differed among sites and years. We used northern bobwhite counts from the North American Breeding Bird Survey (NABBS) to test whether local effects of snow accumulation on winter survival manifest in population reductions up to 5 years following locally extreme snow accumulation events on 128 routes in the northern bobwhite range. Our best‐supported linear mixed model showed snow accumulation during 4 preceding winters was associated with population declines, with declining associations between abundance and snow accumulation over longer time lags. Our NABBS analysis linked local demographic effects from the radiotelemetry study to population‐level changes in abundance at a wide geographic scale, collectively illustrating the capacity for comparatively rare but severe winter weather events to produce a legacy of population change among northern populations. Conservation strategies for these populations should take into account the potential effect of severe winter weather on population stability and seek to employ conservation measures that increase resiliency to severe winter weather events. © 2017 The Wildlife Society.

ABSTRACT Stocking pen‐raised northern bobwhite (Colinus virginianus) into habitats inhabited by wild bobwhite is a widespread practice, yet no technique other than marking exists to distinguish between these birds when they are harvested or recaptured. We assessed the potential of stable isotope analysis of primary feather tissue to distinguish between wild and pen‐raised bobwhite. We obtained 104 feather samples from 3 game farms and 3 hunters in New Jersey, USA, collected between 1998 and 2006. We analyzed all samples for isotopes of carbon13C/12C, nitrogen15N/14N, sulfur34S/32S, and a preliminary sample for hydrogen2H/1H. Combinations of isotopic ratios of carbon, nitrogen, and sulfur yielded unique patterns for the 2 groups, enabling us to form a significant function that discriminated between these groups 100% of the time. The function was influenced most by the isotopic ratios of nitrogen and carbon. We were unable to discriminate between age classes or sex within groups, but could discriminate among farms and between years for the one farm where we had 2 years of samples. In our pilot study, stable isotope analysis of primary feather tissue was a reliable technique for distinguishing wild and pen‐raised bobwhite for 12–14 months following postjuvenal or postnuptial feather molt. Summer stocking, feeding stations, or long‐term survival of pen‐raised birds would reduce the efficacy of this technique, depending upon the definition of a wild population. © 2017 The Wildlife Society.

ABSTRACT Captive rearing and release of birds in the order Galliformes remains a popular management tactic despite low survival rates. We investigated avian predator selection of captive‐reared northern bobwhites (Colinus virginianus) as a potential driver of their high mortality. We simulated avian predator hunts on a flushing pair of bobwhites during trials conducted from 6 February 2015 to 14 February 2015 in Texas, USA. When presented a choice of a captive‐reared bobwhite or wild bobwhite, a Harris's hawk (Parabuteo unicinctus) pursued a captive‐reared bobwhite in 8 of 10 flight trials. This selective rate, combined with observations from auxiliary research indicate avian predation may be a greater risk for captive‐reared birds than wild birds. The success of captive‐rearing and release efforts may benefit from a better understanding of how to more adequately prepare captive‐reared birds for release. © 2018 The Wildlife Society.

ABSTRACT Increased mortality rates of northern bobwhites (Colinus virginianus) raised in captivity and stocked into the wild compared with wild bobwhites may be due to differences in antipredatory behaviors. We assessed behavior of wild and pen‐raised bobwhites foraging under risk of predation in a captive situation at the Tennessee Tech University Avian Research Facility, Cookeville, Tennessee, USA, during March–April 2008 and February–March 2009. We hypothesized wild bobwhites were more sensitive to predation risk than pen‐raised bobwhites and evaluated the relative contributions of time allocation, vigilance, and foraging efficiency in avoiding predation among wild and pen‐raised bobwhites. Coveys of 4 bobwhites were presented with 3 food patches at presumed safe, moderately risky, and risky distances from cover in 10‐hr trials. Food consumption, vigilance, time allocation, foraging efficiency, and average realized covey size were measured using video recordings for each patch, and compared between wild and pen‐raised bobwhites and among patch risk levels. Both wild and pen‐raised bobwhites foraged more in safe patches than in riskier patches. Vigilance rates were similar between wild and pen‐raised bobwhites. However, pen‐raised bobwhites spent more time foraging at riskier patches than did wild bobwhites. Wild bobwhites foraged more efficiently than did pen‐raised bobwhites, with foraging efficiency of wild bobwhites increasing in risky patches. Greater foraging efficiency and associated shorter foraging time among wild bobwhites may make them less susceptible to predation than pen‐raised bobwhites. © 2016 The Wildlife Society.

ABSTRACT Trapping of northern bobwhites (Colinus virginianus) is commonly conducted for research purposes. We investigated the influence of weather, lunar phase, time of day, and season on bobwhite trapping success in the Rolling Plains ecoregion of Texas, USA, from 2009 to 2011. We trapped bobwhites in autumn (Oct–Nov) and spring (Feb–Mar) using walk‐in funnel traps baited with sorghum. We used a negative binomial regression to examine effects of temperature, humidity, wind speed, lunar phase, time of day, season, the number of traps set, and year on the number of bobwhites captured per trapping session. More bobwhites were trapped during the spring, in the evenings, and when temperatures were cooler. There was also some evidence for an influence of lunar phase on the number of bobwhites captured with greater counts during the new moon and third quarter. These variables may be important to consider for maximizing catch‐per‐unit‐effort, when using trapping data to estimate relative abundance, or when conducting mark–recapture studies. © 2016 The Wildlife Society.

ABSTRACT Long‐term data from the Breeding Bird Survey and Christmas Bird Count indicate that northern bobwhite (Colinus virginianus; hereafter, bobwhite) populations have declined since 1961 in all but 1 of the 31 states they occupy within the United States. This long‐term population decline is largely due to habitat loss. However, several other factors, including parasitism, have been considered as possible contributors or even primary causes of the bobwhite population decline. We review recent research on the helminths that infect bobwhites, particularly in Texas, and compare the bobwhite–helminth system to other galliform–helminth systems. We hypothesize that helminths do not affect bobwhite populations under favorable habitat conditions and that any observed localized population impacts may be proximate causes of the bobwhite population decline rather than ultimate causes of the bobwhite population decline. Helminth survey data provide insufficient evidence of negative effects on individual bobwhites or on their populations. Although surveys provide important data and should continue, experimental studies are the best way to identify the impact that helminths may have on bobwhites at the population level. © 2016 The Wildlife Society.

ABSTRACT Captive‐rearing and release programs have been used to augment populations of ring‐necked pheasant (Phasianus colchicus), northern bobwhite (Colinus virginianus), and other gamebirds to provide additional hunting opportunities. However, many question the efficacy of the rear‐and‐release technique to increase huntable gamebird populations. The Surrogator® (hereafter, surrogator) is a captive‐rearing system purported to establish huntable gamebird populations within a property. Little research has been conducted to inform land managers and sportsmen and sportswomen about the effectiveness of this system. We evaluated the use of the surrogator for ring‐necked pheasants and northern bobwhites from May to October 2009 and 2010 in Kiowa County, Kansas, USA. The 4‐week in‐surrogator survival rates for pheasant chicks were 85% ± 5% (SE) in 2009 (n = 840) and 79% ± 8% in 2010 (n = 420). The 5‐week in‐surrogator survival of bobwhite chicks was 78% ± 12% (n = 765) in 2009 and 79% ± 3% in 2010 (n = 783). Released pheasant chicks had an overall survival rate of 8% ± 6% (n = 58) over 12 weeks. Eight‐week postrelease survival for bobwhites was 35% ± 5% (n = 59). Postrelease survival of pheasants or bobwhites was not appreciably greater than conventional rear‐and‐release programs, suggesting that population establishment with surrogator birds may be difficult. Although 1,150 pheasants and 1,105 bobwhites were released, only 5.5% and 7.2% of bands were returned from harvested pheasants and bobwhites, respectively. The surrogator may not be effective for establishing or re‐establishing pheasant and bobwhite populations, but it may be an effective tool to supplement existing gamebird populations to enhance hunting opportunities. © 2016 The Wildlife Society.

ABSTRACT We determined autumn and winter food habits of hunter‐harvested northern bobwhites (Colinus virginianus; n = 388) over 11 years (1998–2009) in a matrix of restored shortleaf pine–bluestem (Pinus echinata–Andropogon–Schizachyrium), and unthinned and unburned stands on the Ouachita National Forest, Arkansas, USA. Restoration treatments involved thinning of midstory hardwoods and midstory and co‐dominant shortleaf pine in a process called wildlife stand improvement (WSI). The WSI was followed by February or March prescribed burns at 3‐year intervals. Species richness of individual bobwhite crops ranged from 0 to 16 and differed among years but not months. Shortleaf pine seed, post oak (Quercus stellata) acorns, and various legume seed (Lespedeza spp., Desmodium spp.) occurred most often of 94 food categories/items (≥110 species) found in quail crops. Shortleaf pine seed had among the highest gross energy (4.58 ± 0.2 kcal/g), fat (21.8 ± 0.6%), and crude protein (31.2 ± 0.5%) of food items analyzed. Green vegetation occurred in 43.3% of all crops, the greatest of any food category, and also was high in crude protein (28.7%), but the lowest in gross energy (3.43 kcal/g). Invertebrates occurred in 35.6% of crops, but were high‐ranked items in autumn and winter diets, particularly Orthopterans (12.4%), which were greatest in crude protein (64.3%). Average dry mass of crop contents was 1.38 g ± 0.16 g. Dry mass of woody plant seeds comprised most of the diet, averaging 0.86 g ± 0.17 g/crop. Bobwhites used a wide variety of plant and invertebrate food items that require or are benefited by open canopy conditions and frequent disturbance such as prescribed fire. © 2016 The Wildlife Society.

ABSTRACT Declines in northern bobwhite (Colinus virginianus) populations have led landowners in Texas, USA, to develop various management strategies to combat waning abundance. One common management strategy is to provide supplemental feed to bobwhites, despite the paucity of information regarding the effects of supplemental feed on bobwhite space use and survival. We examined survival and home range of bobwhites using the technique of spreading supplemental feed into roadside vegetation in the Texas Rolling Plains. The study sites were divided into 8 (404.6‐ha) units randomly designated as treatment (feed provided) or control (feed withheld). Treatment and control units were rotated during the second field season to minimize potential habitat bias. Treatment units received approximately 69.1 kg/km of milo (Sorghum bicolor) twice per month. We captured and radiomarked 197 female bobwhites (82 treatment [48: 2010–2011; 34: 2011–2012], 115 control [64: 2010–2011; 51: 2011–2012]) from autumn 2010 to spring 2012. Females were monitored for location and survival with radiotelemetry 3–4 times/week. Average home‐range size was similar on control and treatment units (47.6 ha [8.7 SE] and 46.2 ha [10.3 SE], respectively). We estimated survival rate with the nest survival model in Program MARK. We observed an increase in survival rate on treatment units compared with control units, regardless of year or environmental conditions. Our results suggest that distributing supplemental feed into roadside vegetation positively influences bobwhite survival with no reduction in home range size. © 2015 The Wildlife Society.

ABSTRACT Northern bobwhites (Colinus virginianus) represent a valuable resource for upland game‐bird hunters and the rural economies they support; however, bobwhite populations are declining across the United States. As ground‐nesting birds, bobwhites are highly susceptible to mammalian predation during the breeding season. We placed global positioning collars on 6 coyotes (Canis latrans), 4 bobcats (Lynx rufus), and 11 raccoons (Procyon lotor) in Texas, USA, during the nesting season of bobwhites (April–August of 2009–2011) to assess their habitat selection and use, as well as determine the relative frequency with which they may encounter bobwhite nests. Overall, nightly encounter rate of predators with known bobwhite nest sites was low. Coyotes encountered nest sites 3 times more frequently than male raccoons and 7 times more frequently than bobcats. Female raccoons did not come within 50 m of any nest locations. The higher encounter rate of coyotes with bobwhite nest sites was associated with the similarity of habitat preference of coyotes and bobwhites for grasslands and grass–shrub habitats and the wide‐ranging nocturnal paths of coyotes. Bobcats and raccoons had shorter nightly paths and mainly used habitats providing a greater degree of cover than is typically suitable for nesting bobwhites. Male raccoons were more mobile than females and made greater use of the grass–shrub habitat, and thus were more likely to encounter quail nests. Despite having lower individual encounter rates with bobwhite nest sites than did coyotes, male raccoons remain important predators of quail nests because they have the behavioral ability to attain greater population densities than those of the more territorial coyotes and bobcats. © 2014 The Wildlife Society.

ABSTRACT Predation risk has a profound influence on prey behavior and habitat use. The Rio Grande Plains ecoregion of Texas, USA, provides a unique opportunity to investigate changes in prey behavior because the ecoregion experiences a high influx of raptors every year during autumn migration. We used an 8‐year data set (2000–2008) of radiocollared northern bobwhites (Colinus virginianus) and raptor abundance to test the hypothesis that bobwhites responded to increased raptor abundance via changes in woody‐cover use at the home‐range scale. Bobwhite survival was negatively correlated with raptor abundance, with red‐tailed hawks (Buteo jamaicensis), and northern harriers (Circus cyaneus) accounting for 51% of the variability in bobwhite survival (P

Abstract Habitat fragmentation is considered a contributing factor to declining populations of northern bobwhite (Colinus virginianus). Some population strongholds exist within large expanses of habitat; however, many regions of the species' range have become fragmented and populations therein have become nearly extirpated. Our objectives were to determine whether combined habitat management and bobwhite translocation could restore bobwhite populations in habitat patches within a fragmented landscape. We translocated 550 bobwhites to 2 sites (≥660 ha; Caldwell and Fayette counties) in the Post Oak Savannah ecoregion of Texas, USA, during 2004–2006. We compared survival, home‐range size, and reproduction between translocated bobwhites in a fragmented landscape and resident bobwhites in contiguous habitat (Brooks County). Pooled over the 3‐year study, translocated bobwhites had lower survival (6 Apr–15 Aug, 2004–2006; Ŝ = 0.35; n = 165 bobwhites) than did resident bobwhites (Ŝ = 0.56; n = 224 bobwhites; P

Abstract The northern bobwhite (Colinus virginianus) decline has become a cause célébre of wildlife conservation during the past 2 decades. With few exceptions, current broad‐scale population trends show ongoing erosion in bobwhite numbers across most of the species' range. The causes of these declines are ultimate factors exacerbated by certain proximate factors. Ultimate factors are centered on the loss and fragmentation of habitat. Proximate factors such as predation and disease also may be present. The impacts of some factors, such as climate change, remain unknown but may influence bobwhite population trajectories over the long term. Progress has occurred in bobwhite conservation efforts since 1990 and has culminated in the formation of the National Bobwhite Technical Committee and the publication of the Northern Bobwhite Conservation Initiative. The vast majority of prevailing agricultural, forestry, and to some extent rangeland land uses in the United States continue as threats to bobwhite population persistence in the foreseeable future. Land‐use patterns that once sustained widespread abundance of northern bobwhite during the early 20th century clearly are past and likely never to return. Landscape features that sustain and elevate northern bobwhite populations will only be maintained as a function of purposeful management actions directed at saving and creating usable space. © The Wildlife Society, 2012

Abstract Distance sampling during aerial surveys has been used extensively to estimate the density of many wildlife species. However, practical issues arise when using distance sampling during aerial surveys, such as obtaining accurate perpendicular distances. We assembled a computerized, electronic system to collect distance‐sampling data (e.g., transect length, detection location, and perpendicular distance) during aerial surveys. We tested the accuracy of the system in a controlled trial and a mock survey. We also evaluated the electronic system during field surveys of northern bobwhite (Colinus virginianus) conducted in the Rio Grande Plains and Rolling Plains ecoregions of Texas, USA, during December 2007–2008. For comparison, we evaluated the accuracy of visual estimation of distance during a mock survey. A strong linear relationship existed between estimated and actual distances for the controlled trial (r2 = 0.99) and mock survey (r2 = 0.98) using the electronic system. Perpendicular‐distance error (i.e., absolute difference between estimated distance and actual distance) for the electronic system was low during the controlled trial (1.4 ± 0.4 m; ${ar {x}}$ ± SE) and mock survey (3.0 ± 0.5 m) but not during the visual estimation of distance (10 ± 1.5 m). Estimates of bobwhite density obtained using the electronic system exhibited reasonable precision for each ecoregion during both years (CV

Abstract Providing supplemental feed is a common practice for the management of northern bobwhite (Colinus virginianus) and scaled quail (Callipepla squamata). The ecological efficacy and economic efficiency of a feeding program for quail can be evaluated using numerous metrics, including visitation rates by target and non‐target species. We quantified species visitation rates seasonally at free‐choice quail feeders with motion‐sensing cameras at 4 sites in West Texas, USA. Feeders were monitored from autumn 2002 to summer 2003 using both an active‐infrared sensing camera system (TrailMaster 1500®; Goodson & Associates, Inc., Lenexa, KS) and a passive infrared video system (TrophyView®; Wildlife Surveillance Systems, Inc., Kerens, TX). Our camera systems recorded 14 mammal and 18 avian species among 6,558 events observed from 490 days of feeder surveillance. Collectively, northern bobwhite and scaled quail accounted for only 7.3% and 11.3% of all recorded species visitations for the TrophyView and TrailMaster camera systems, respectively. Raccoons (Procyon lotor, 43.2%) and nongame birds (32.5%) comprised the majority of all recorded visitations. Although feeder visitation rates do not necessarily equate to feed consumption, we conclude that the vast majority of the feed in this study was consumed by non‐target species and most notably raccoons. High visitation rates by raccoons at feeders suggest supplemental feeding programs for quail could facilitate targeted removal of a common feed competitor (and potential predator of quail nests) and perhaps improve efficacy of feeding efforts. Managers should consider both direct and indirect effects of providing supplemental feeding efforts. © 2012 The Wildlife Society.

Abstract Loblolly pine (Pinus taeda) plantations are established using various treatments to manage competing vegetation and increase pine production. Although young pine plantations historically supported early successional vegetation communities that contained abundant wildlife forage, increasing intensity of stand‐establishment treatments, particularly herbicides, has caused concern regarding potential effects on composition, availability, and quality of wildlife forage within young pine plantations. Few long‐term studies have described relationships between intensity of site preparation and effects on important forage plants for 2 economically and ecologically important game species: white‐tailed deer (Odocoileus virginianus) and northern bobwhite (Colinus virginianus). Therefore, we examined effects of 6 treatments of increasing stand‐establishment intensity via combinations of mechanical and chemical site preparation with herbaceous weed‐control on deer and bobwhite food plants from 1 year to 8 years after site preparation in loblolly pine plantations (n = 6) within pocosins in the Lower Coastal Plain of North Carolina, USA, during summers of 2002–2005, 2007–2009. Although woody and vine forage plants for deer and quail were common on all treatments, chemical site preparation resulted in long‐term decreases (approx. 50% for 8 yr) in coverage of these plants. Type of mechanical site preparation–spacing and herbaceous weed‐control had few effects on woody and herbaceous deer and quail food plants. Dissimilar from research in other regions, reduction in woody cover did not provide a concurrent increase in herbaceous food plants. Because of relatively poor forage quality in pocosin habitats, vegetation management practices may reduce deer and quail food quantity without increasing quality. However, because abundance of low‐quality forage is high in pocosin habitats, localized forage reductions due to site‐preparation techniques may not affect overall carrying capacity in these areas. © 2012 The Wildlife Society.

Abstract There is a paucity of information concerning northern bobwhite (Colinus virginianus) chick demography caused by a deficiency of efficient published capture techniques and permanent unique markers for identification. In order to facilitate chick research, we employed a thermal camera to detect and capture chicks during the preflight stage (≤14 days old) brooded by a radiomarked female. We released a known number of chicks into native vegetation within a flight pen to test this technique. Observers (unaware of the number) then used a thermal camera to successfully count (≥95% intra‐class correlation coeff.; complete counts for each age class) and capture the chicks. In separate field tests, we homed to within 10 m of the roost location of wild radiomarked females before sunrise, circled the area until the brood heat signature was observed, and flushed the female from the chicks. We located 116 chicks from 43 broods with the thermal camera throughout the 2011 nesting season with 81% complete, 12% partial, and 7% failed captures attempts. Detection of chicks by the thermal camera was not affected by age. Complete brood abandonment was not detected as a result of capture events. The employment of a thermal camera to capture chicks should advance the success and efficiency of capture and thus promote research concerning brood ecology. © 2012 The Wildlife Society.

Abstract We assessed the effects of using a broadcast caller during surveys and increasing survey duration to estimate northern bobwhite (Colinus virginianus) density and occupancy. From 15 May 2009 to 15 August 2009, we conducted repeat‐visit breeding bobwhite surveys at 180 sites in Delaware, USA. Increasing survey duration from 3 min to 7 min, or using a broadcast caller, improved detection probability for a single visit by 52% and 42%, respectively. However, density estimates when using a broadcast caller were biased high—≥3 times greater compared to passive‐listening surveys. Density estimates for 3‐min and 7‐min passive surveys were not different. Additionally, bobwhite occupancy was similar among all 3 survey treatments. Use of a broadcast caller to survey for bobwhites appears to violate the assumption of distance sampling that an individual is detected prior to movement. Use of a broadcast caller is inappropriate for determining density estimates through distance sampling, but may be appropriate for determining site occupancy. © 2011 The Wildlife Society.

Abstract We compared 4 external radiotransmitter attachment techniques to determine the optimum attachment method on chicks of 2 galliform species. The attachment methods included tissue glue, silicone gel, suturing, and leg harness. The study was conducted in captivity with a 2‐phase assessment: first with northern bobwhite (Colinus virginianus), and then chukar (Alectoris chukar) chicks. We applied each technique and assessed effects on growth rates, retention times, ease of attaching the transmitter, and effects on physical development. No apparent adverse impacts on chicks were observed for any of the attachment techniques. We found the leg‐harness technique was most reliable in terms of retention time, required the least amount of handling time, and was the simplest to administer. Modifications to our suture technique likely would result in similar retention times, but would still require additional handling time and complexity in attaching transmitters. © 2011 The Wildlife Society.

The Northern Bobwhite (Colinus virginianus) is an economically important game bird within the Rolling Plains Ecoregion. Within this region, bobwhite is experiencing extreme cyclic population fluctuations which are resulting in a net decline in total population. It is suspected that within this region two helminth parasites, an eyeworm (Oxyspirura petrowi) and a cecal worm (Aulonocephalus pennula), are contributing to this phenomenon. However, this has been difficult to study as the primary mode of investigation would be the deployment of anthelmintic treatment. Unfortunately, no registered treatments for wild bobwhite currently exist. Thus, utilizing an anthelmintictreatment for wild bobwhite would require registration of that treatment with the U.S. Food and Drug Administration (FDA). As bobwhite are game birds that are hunted, they are considered food-producing animals to the FDA, and as such require the assessment for the withdrawal of the drug residues to be assessed for human food safety. In this study, we optimized and validated a bioanalytical method for the quantification of fenbendazole sulfone in bobwhite following the U.S. FDA Center for Veterinary Medicine Guidance for Industry #208 [VICH GL 49 (R)] for assessment of fenbendazole sulfone drug residue in Northern bobwhite liver. The official method for quantifying fenbendazole sulfone in domestic chicken (Gallus gallus) was adapted for use in bobwhite. The validated method quantitation range is 2.5-30 ng/mL for fenbendazole with an average recovery of 89.9% in bobwhite liver., (© 2023 John Wiley & Sons Ltd.)