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Passive acoustic monitoring is a valuable ecological and conservation tool that allows researchers to collect data from vocal species across large geographic areas and temporal spans. Grassland bird populations, many of which are indicators of ecosystem health, have experienced precipitous declines over the past several decades. Acoustic monitoring of grassland bird populations provides opportunities to monitor declines and focus conservation practices, yet the ability to identify species efficiently and accurately from acoustic data is challenging. Therefore, development of automated classifiers such as convolutional neural networks (CNNs) are at the forefront of streamlining detection and identification of individual species. Here, we present a CNN classifier for 5 key grassland bird species across southcentral Oklahoma, a part of the southern Great Plains: northern bobwhite (Colinus virginianus), painted bunting (Passerina ciris), dickcissel (Spiza americana), eastern meadowlark (Sturnella magna), and Bell's vireo (Vireo bellii). We compiled a high‐quality training dataset consisting of 6,933 calls, built semiautonomously using template matching that can be expanded easily to any bird species of interest. Our trained multilabel CNN achieved a high level of classification accuracy (≥98%) for the 5 species using the library of test calls and field recordings played using a programmable game caller. The ability to conduct acoustic wildlife surveys across large spatial extents will allow for more efficient monitoring of wildlife to determine key population parameters and trends and effects of biotic and abiotic factors (e.g., vegetation, disturbance, weather) on these key species. [ABSTRACT FROM AUTHOR]

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 FROM AUTHOR]

Fields dominated by nonnative grasses, such as tall fescue (Schedonorus arundinaceus), are being restored to native plant communities across the eastern U.S. Upon restoration, disturbance is necessary to maintain native communities in an early seral stage, and plant response to different management practices is of interest to managers to guide habitat enhancement for various wildlife species. We evaluated effects of burning and mowing following restoration of native plant communities via 2 methods (planting native grasses and forbs and seedbank response without planting), across 11 replicated sites in Tennessee and Alabama, 2019–2020. We compared vegetation composition and structure, openness at ground level, forage availability, and nutritional carrying capacity (NCC) following 4 treatments (Seedbank Burned, Seedbank Mowed, Planted Burned, Planted Mowed, and tall fescue Control), and we related these measurements to the food and cover requirements for 3 popular game species: white‐tailed deer (Odocoileus virginianus), wild turkey (Meleagris gallopavo), and northern bobwhite (Colinus virginianus). The combination of planting and mowing increased grass coverage, whereas units that were established via seedbank response and managed by burning had greater forb coverage. Visual obstruction above 25 cm was greater in all treatments than Control, which provided cover that has been described as selected nesting cover by wild turkey and bedding cover for deer. Openness at ground level, which is especially important for bobwhite and wild turkey broods, was 30% greater in Seedbank Burned than Planted Mowed where we recorded the least openness among treatments by the second year of treatment. Similarly, coverage of bobwhite food and deer forage plant species was greatest in Seedbank Burned. Biomass (kg/ha) of plant species known to be selected as forage by deer was greater in all treatments than in Control, and NCC (deer days/ha) was greatest in Seedbank Burned by year 2. Our results highlight differences in plant composition and structure following management of early successional communities. Where possible, we encourage managers to use fire instead of mowing to maintain plant communities, especially if food plants and enhanced structure at multiple levels for bobwhite, wild turkey, and deer are management objectives. Furthermore, our results illustrate planting native grasses and forbs is not necessary to restore native early successional plant communities on most sites. [ABSTRACT FROM AUTHOR]

Distance sampling from aerial platforms can provide researchers with precise and efficient density estimates for wildlife populations, particularly over large areas. The intensity of the distance sampling survey depends on the survey effort. Effort can be referred to as coverage, where transect spacing is determined by the observer's sightability distance of the object or animal. Managers and researchers in Texas often use helicopters to survey and collect data for northern bobwhite (Colinus virginianus) density estimates. For bobwhites, 100% coverage represents transect spacing of 200 m, assuming observers can cover out to 100 m on either side of the transects. Often surveys are conducted at 50% coverage or 400 m spacing to reduce cost. Still, the implications of lowering survey effort on the precision of density estimates are unknown, particularly in coverage prescriptions. We flew 2,641 km of line transects each December from 2014 to 2017 and detected 2,333 bobwhite coveys across 7,648 ha of rangeland on the San Antonio Viejo Ranch in Jim Hogg County, TX, USA. We conducted line‐transect distance sampling from a helicopter platform at 50 and 100% coverage and simulated results at coverage <50% using empirical data. Based on the results of simulated surveys at <100% coverage, surveying for bobwhites using helicopters with less than 50% coverage results in variable density estimates (wide 95% confidence intervals) and low precision (coefficient of variation >20%). Empirical surveys conducted at 50 and 100% coverage show little variation in density estimates between the 2 levels of coverage. However, when broken into substrata (areas less than ~1,000 ha), conducting surveys at 50% coverage resulted in <60 detections, which led to low precision in density estimates (coefficient of variation >20%). Our results are based on surveys conducted at the juncture of the Coastal Sand Sheet and Tamaulipan Thorn Scrub ecoregions in south Texas and need to be evaluated in other arid and semi‐arid rangeland systems. [ABSTRACT FROM AUTHOR]

Restoration of early successional plant communities dominated by nonnative plant species is a central focus of many state and federal agencies to improve habitat for wildlife associated with these communities. Restoration efforts largely have concentrated on controlling nonnative species followed by planting native grasses and forbs. However, there are numerous establishment problems associated with planting that warrant evaluation of alternative approaches for restoration. We conducted a field experiment to compare vegetation composition and structure as related to habitat for focal wildlife among plant communities established by planting (Planted) native grasses and forbs and revegetation from the seedbank (Seedbank) without planting following control of tall fescue (Schedonorus arundinaceus) at 15 replicated sites in Tennessee and Alabama, USA. Planted and Seedbank treatments produced similar plant communities. Vegetation structure providing cover for nesting and brooding northern bobwhite (Colinus virginianus) and wild turkey (Meleagris gallopavo) was similar between Seedbank and Planted treatments except native grass cover was greatest in Planted, and we recorded greater openness at ground level in Seedbank than Planted or tall fescue control (Control). Abundance of northern bobwhite food plants and selected white‐tailed deer (Odocoileus virginianus) forage were similar between Planted and Seedbank treatments, but nutritional carrying capacity for deer was greatest in Seedbank. Despite similarities in food abundance, and even though all forbs included in the planting mixtures were food plants, the majority of food plants in Planted were from the seedbank. The compositional and structural characteristics deemed most influential in previous studies to selection of breeding sites by dickcissel (Spiza americana), field sparrow (Spizella pusilla), grasshopper sparrow (Ammodramus savannarum), Henslow's sparrow (Ammodramus henslowii), and northern bobwhite were similar in Planted and Seedbank. Tall fescue Control was most similar to characteristics of eastern meadowlark (Sturnella magna) breeding sites. Revegetation following Seedbank produced a plant community that provided habitat for many wildlife species equal to or better than Planted and was 3.7 times less expensive than Planted. © 2021 The Wildlife Society. Planting a native seed mixture following tall fescue control was not necessary in Tennessee and Alabama to establish a native early successional plant community beneficial to conservation‐priority grassland birds, northern bobwhite, wild turkey, or white‐tailed deer. Land managers should consider managing the natural seedbank response following eradication of nonnative species and spot‐treat undesirable plant species rather than routinely planting native grasses and forbs when restoring native early successional plant communities for wildlife. [ABSTRACT FROM AUTHOR]

Repeated prescribed fire can create and maintain areas with sparse overstory tree cover and a dense grass‐forb‐shrub understory, providing habitat for northern bobwhite (Colinus virginianus; hereafter, bobwhite). Despite potential benefits of prescribed fires for conserving bobwhite habitat, burning during the nesting season may destroy bobwhite nests and reduce available nesting cover. We monitored radio‐transmittered bobwhite (n = 104) from 2016 to 2018 to describe nest‐site selection and determine the risk of nest destruction on a 17,000‐ha North Carolina military installation, Fort Bragg, managed with rotational growing‐season and dormant‐season prescribed fires on an approximate 3‐year return interval. We located 48 nests, of which 8 (16%) were in areas burned the same year, 9 (19%) were in one‐year post fire, 25 (52%) were in 2‐years post fire, and 6 (13%) were in ≥3‐years post fire areas. We compared vegetation composition and structure at nests to nearby random locations and determined bobwhite selected nest sites with greater woody understory and wiregrass cover, lower basal areas of pines and hardwoods, and less distance to the nearest road. Two nests (6.7%) were destroyed during prescribed fires, but success of incubated nests was high (67%). We calculated the overall risk of nest destruction by prescribed fire as the proportion of active nests in areas with ≥3 years since last fire multiplied by the proportion of the study area burned each week. Overall, 11% (weekly x̅ = 0.75%, range = 0–3%) of the study area was burned during the 2016 nesting season (3 June to 3 September), 4% (weekly x̅ = 0.31%, range 0–2%) of the study area was burned during the 2017 nesting season (5 June to 2 September), and 7.5% (weekly x̅ = 0.58%, range 0–5%) of the study area was burned during the 2018 nesting season (3 June to 31 August). We estimated that no more than 0.75% of bobwhite nests across the study site were exposed to fire annually. Most growing‐season fires occurred before the bobwhite nesting season, which limited direct effects of prescribed fire on bobwhite nest survival. However, shifting prescribed fires to later in the growing season to better match the historical lightning season (i.e., after 1 June) would increase the risk of nest destruction. Because bobwhite used older roughs (i.e. areas 2 years since fire) for nesting, shortening the fire return interval to less than 3 years would increase the proportion of nests exposed to fire. Additionally, a shortened fire return interval would decrease available nesting cover, especially in regions with low soil fertility where vegetation change following fire is less rapid than on more productive soils. © 2021 The Wildlife Society. : A fire return interval less frequent than every 2 years likely is necessary to maintain nesting cover and reduce risk of nest destruction, for bobwhite quail especially on less productive soils as are common in the Sandhills physiographic region of the southeastern USA. [ABSTRACT FROM AUTHOR]

Creating early successional vegetation on working farms can increase northern bobwhite (Colinus virginianus; hereafter, bobwhite) abundance with little reduction in crop production, but specific effects of field border establishment on bobwhite nesting ecology are not well understood. We monitored bobwhite nesting on a 1,740‐ha working farm with 19% of property managed for early successional vegetation in southeastern North Carolina, USA. We monitored 133 radio‐marked bobwhites from 1 April to 30 September in 2014 and 2015. We modelled nest‐site selection by comparing paired nest and random reference sites and modeled effects of habitat covariates on daily nest survival. Forb, shrub, and native warm‐season grass cover were greater at nest sites than reference sites with forb cover the strongest predictor of nest‐site selection. Bobwhite nested at a greater density in areas managed for fallow vegetation (1 nest/3 ha) than in planted warm‐season grasses and forbs (1 nest/5 ha). The daily nest survival rate over 2 years was 0.964 (SE = 0.007), and was not significantly influenced by any modeled covariate. Naïve nest success (nest successes/total nests) was 46.9%. The importance of forbs as nesting cover indicates bobwhite abundance in areas dominated by row‐crop agriculture may be limited by low nest initiation from a lack of herbaceous nesting cover. Hence, the creation of fallow herbaceous vegetation on working farms should be prioritized to increase bobwhite reproduction within agricultural landscapes. Furthermore, planting warm‐season grasses is not necessary because volunteer forbs and grasses provide as good or better nesting cover and can be less costly to establish. © 2020 The Wildlife Society. Establishing early successional vegetation along field edges and on unproductive cropland is a common method for restoring northern bobwhite (Colinus virginianus) habitat within agricultural landscapes. We modelled the influence of vegetation components on northern bobwhite nest‐site selection and nest survival on a working farm to inform management efforts; results suggest proportion of forb, shrub, and native warm‐season grass cover were greater at nest sites than random reference sites with forb cover the strongest predictor of nest‐site selection. [ABSTRACT FROM AUTHOR]

Detailed information on movements, space use, and habitat selection patterns by northern bobwhite (Colinus virginianus; hereafter, bobwhite) is important for understanding population dynamics, gene flow, disease spread, and development of habitat management activities. Advances in Global Positioning System (GPS) technology has allowed researchers to collect spatial and temporal location data with increasing accuracy, which in turn has shifted the resolution at which habitat evaluations and management focus can occur. Only recently have GPS tags been deployable for small ground‐nesting birds. We conducted a preliminary examination of the spatial ecology of 74 bobwhites equipped with GPS tags during breeding and covey season on 3 private properties in north‐central Texas, USA, during 2015–2017. Specifically, we derived daily estimates of core area and range size using dynamic Brownian bridge movement models, daily distance traveled, and distance between consecutive roost sites. Bobwhites tended to move more during breeding than covey season. Consecutive roost sites were, on average, approximately 130 m apart. Daily core area and home range size of bobwhites across the calendar year were 1.99 ± 0.13 and 6.29 ± 0.85 ha, respectively. During the breeding season, bobwhites avoided hardwood communities and showed no selection or avoidance of shrub, grass, and herbaceous communities. During covey season, bobwhites selected for herbaceous, grass, and hardwood communities, and neither selected nor avoided shrub communities. Global Positioning System data on a variety of species has become the primary information used for habitat and conservation management decisions, therefore, future research on bobwhite will include the application of GPS, which our results show can increase the temporal resolution of information and be used for habitat conservation and restoration actions. © 2020 The Wildlife Society. Advances in Global Positioning System (GPS) technology has allowed researchers to collect spatial and temporal location data with increasing accuracy, and only recently have GPS tags been deployable for small ground‐nesting birds such as northern bobwhite. We demonstrate daily patterns in movements and selection of 74 northern bobwhite equipped during breeding and covey season on 3 private properties in north‐central Texas, USA, during 2015–2017. [ABSTRACT FROM AUTHOR]

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 <7 days. The probability of retaining a radiotransmitter for the duration of our 8‐week study was 0.76 (±0.08 SE), 0.89 (±0.09 SE), and 0.00 for normal suture, our modified suture, and glue‐on techniques, respectively. Development and growth of suture‐ and patagial‐tagged bobwhite chicks (average mass gain of 41.95 g ± 2.79 SE) was unimpeded compared with a control (patagial‐tagged only, no transmitter) group of birds (average mass gain: 40.89 g ± 2.91 SE). We observed similar tag‐retention rates (0.906 ± 0.07 SE) of transmitters affixed to wild bobwhite chicks in the field using a modified‐suture technique compared with the aviary study. Our modifications to the traditional suture methods include changing the placement of the transmitter to reduce snag rate in vegetation, using a smaller gauge syringe needle to reduce skin‐tearing, applying a surgeon's knot for increased knot‐security and reduced knot slippage while suturing, and applying insta‐set spray to rapidly dry superglue to reduce handling time of chicks. The modified‐suture technique provides improvements in tag‐retention, facilitates shorter handling time of birds in the field, and provides an effective means for tagging and tracking individuals to collect ecological data and demographic vital rates on bobwhite chicks and other birds. Future studies should investigate potential sublethal effects that suture tags may impose on individuals to identify and account for estimable biases of vital rates. © 2020 The Wildlife Society. Limited data exist on game birds with precocial young because of the difficulty of capturing and tagging small, rapidly growing chicks with miniature tracking devices. The modified suture technique we have developed provides a technique for quickly and reliably affixing miniature radiotags to bobwhite chicks, affording a new window of opportunity into their ecology. [ABSTRACT FROM AUTHOR]

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. Capturing northern bobwhites is a critical component of many research projects, and identifying factors that increase capture success can save time, money, and improve inference. 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. [ABSTRACT FROM AUTHOR]

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. We evaluated the potential of an automated recording device to detect and survey northern bobwhite covey calls. With thorough consideration of technological and survey constraints, we believe automated recording device technology can provide valuable opportunities for monitoring northern bobwhite populations. [ABSTRACT FROM AUTHOR]

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. Large‐scale cooperative conservation efforts, while becoming more common, are challenging and complex. We explore 2 interstate initiatives that have demonstrated pathways to success and offer strategies to emerging and future initiatives of this nature. [ABSTRACT FROM AUTHOR]

Grasslands were once common in the eastern United States and provided habitat for numerous grassland‐dependent wildlife. However, native grasslands in this region have largely been eliminated as a result of conversion to other land uses (e.g., urban development, row‐crops), altered disturbance regimes (e.g., lack of fire and grazing), or conversion to introduced grasses for livestock production. Consequently, many wildlife species adapted to these environments have experienced protracted population declines, notably, northern bobwhite (Colinus virginianus), and other grassland‐dependent bird species. Restoration of native grasslands with appropriate native plant species composition, structure, and disturbance regimes will be key to restoring at‐risk wildlife. Indeed, the region still includes >20 million ha of grasslands, but these are dominated by introduced grass species and focused on cattle (Bos taurus) production. Any successful restoration strategy must engage the agricultural community, provide profitable forage production, and benefit habitat for wildlife. Furthermore, grassland ecosystems in humid regions (i.e., >95 cm annual rainfall) require frequent disturbance to prevent succession to forested conditions. Historically, these native grasslands were maintained by fire, herbivory, and their interaction. Consequently, wildlife communities in humid, native grasslands are adapted to those same disturbances and the conditions they create. Improving species composition by replacing introduced, sod‐forming grass species commonly used in production agriculture (e.g., tall fescue [Schedonorus arundinaceus] and bermudagrass [Cynodon dactylon]) with native grasses can be beneficial but must be accompanied by appropriate disturbance to achieve and maintain improved habitat. Therefore, developing a business case for producers to incorporate native grasses into regional agro‐grasslands that include disturbance through grazing may foster large‐scale improvements in habitat quality. Although Farm Bill conservation practices can make important contributions to conservation of eastern grassland‐dependent wildlife, such programs are dependent on uncertain and limited federal budgets and, to provide appropriate disturbance, require management intervention at a net cost to landowners and Farm Bill programs. Thus, there exists an opportunity to improve habitat at a scale that has the potential to sustain viable populations of grassland‐dependent wildlife. Therefore, we discuss the potential of a new conservation paradigm, one based on grazing systems that utilize native grasses, for filling that conservation gap. © 2019 The Wildlife Society. The duration and severity of the decline of grassland‐dependent bird populations across the eastern United States requires a conservation strategy that takes a large‐scale approach that can affect the extensive working lands of this region. We discuss the potential of a working‐lands conservation model based on objectives of forage managers, grassland‐dependent bird habitat needs, and emerging research regarding grazing and grassland habitats. [ABSTRACT FROM AUTHOR]

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. Reversing the range‐wide decline in northern bobwhite abundance requires conservation actions on private land, but little is known about how private land managers make decisions regarding developing bobwhite habitat. Using a choice‐based conjoint approach we demonstrate that land managers can be grouped into several segments based on their management goals, and most segments do not place a high value on bobwhite hunting opportunities, but instead are most interested in minimizing labor input (i.e., ≤30 days/year) followed by limiting out‐of‐pocket costs (i.e., cost shares ≥ 50%). [ABSTRACT FROM AUTHOR]

Northern bobwhite (Colinus virginianus) populations are monitored using 2 general approaches—population indices and abundance estimators. Due to their convenient sampling designs, indices are commonly used by land managers and researchers to predict or estimate hunting‐season populations. We evaluated the efficacy of 4 bobwhite indices (spring cock [adult male] call‐counts, autumn covey call‐counts, roadside surveys, and helicopter surveys) to predict hunting‐season population size by relating them to abundance estimators (minimum known population [no. unique trapped individuals each year], mark–recapture, helicopter‐based distance sampling). Data were collected at the Rolling Plains Quail Research Ranch in Fisher County, Texas, USA, during 2009–2018. Spring cock call‐counts and autumn covey call‐counts were analyzed at 2 spatial scales: ranch scale (1,781 ha) and point scale (i.e., within the presumed radius of audibility of listening points; 600 m or 113 ha). Roadside and helicopter surveys were conducted at the ranch scale along 31‐ and 90‐km transects, respectively. At the ranch scale, mean spring cock call‐counts were a modest predictor of minimum known populations (r2 = 0.54) and good predictor of mark–recapture estimates (r2 = 0.80). At the point scale, the mean number of cocks heard was a poor predictor of densities surrounding points (r2 = 0.0003) as estimated by distance sampling. The mean number of coveys heard during autumn counts was a significant predictor of both minimum known populations (r2 = 0.88) and mark–recapture estimates (r2 = 0.85) at the ranch scale but was a weak predictor of densities immediately surrounding listening points (r2 = 0.22). Helicopter surveys during November (individuals/km) were a significant predictor of minimum known populations (r2 = 0.98) and mark–recapture (r2 = 0.93). Overall, roadside surveys (individuals/km) conducted during September was the best index for predicting minimum known populations (r2 = 0.99) and mark–recapture estimates (r2 = 0.97). Our results suggest the linear relationship between indices and autumn–winter populations for bobwhite are stronger when conducted closer in time to hunting season and at larger scales. © 2019 The Wildlife Society. This study was conducted to evaluate linear relationships between commonly adopted indices and abundance estimators for northern bobwhite (Colinus virginianus) in the Rolling Plains of Texas, USA, for practitioners seeking to predict or estimate autumn hunting populations. We found that indices conducted at larger scales and closer in time to hunting season may be considered more reliable for predicting abundance. [ABSTRACT FROM AUTHOR]

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. Neonicotinoid compounds were detected in trace amounts in the livers of northern bobwhite quail. Signs of testicular degeneration (n = 2) and lipid‐type hepatocellular vacuolation (n = 8) were consistent with known results of neonicotinoid intoxication. A population‐level ecological risk assessment would provide a more complete understanding of the impacts of neonicotinoid use in Texas, USA, on bobwhite population declines. [ABSTRACT FROM AUTHOR]

ABSTRACT: Cottonseed products have been used as a feed supplement for ruminant livestock and white‐tailed deer (Odocoileus virginianus). Gossypol, a secondary plant metabolite found in cotton (Gossypium spp.), is known to be toxic to a variety of animals, specifically monogastric mammals and birds. However, there are no published data regarding the effects of gossypol in northern bobwhites (Colinus virginianus). Our goal was to determine whether ingestion of gossypol presents a threat to northern bobwhite survival and reproduction. We performed this study at Tarleton State University Northern Bobwhite Research Center (Stephenville, TX, USA) during March and April 2016, using the Environmental Protection Agency's 850.2100 Guideline: Avian Acute Oral Toxicity Test. We administered one‐time doses of refined gossypol to northern bobwhites at 20 mg/kg, 200 mg/kg, 262 mg/kg, 342 mg/kg, 447 mg/kg, 585 mg/kg, 765 mg/kg, and 1,000 mg/kg body weight (BW) and observed them daily throughout a 14‐day period. We measured feed consumption daily and body mass weekly. Birds receiving larger doses (447–1,000 mg/kg BW) consumed less total feed postdosing (55.46 ± 56.46 g, n = 39) and had greater, negative postdosing percent change in mass (−23.02 ± 13.04%, n = 85) compared with control birds and those receiving lower doses (20–342 mg/kg BW). We also examined laying performance and egg quality of birds dosed with 20 mg/kg and 200 mg/kg BW (n = 30 pairs) and the growth rate and percent mortality of second‐generation young produced from these pairs. There was no difference in laying performance, egg quality, the percentage of chicks that hatched, and the growth rate and percent mortality of chicks between the dosing rates. Our results suggest that gossypol can have adverse effects on feed consumption and body mass in northern bobwhites at sufficient doses; however, a one‐time acute dose of gossypol up to 200 mg/kg BW does not pose any negative reproductive effects. © 2018 The Wildlife Society. [ABSTRACT FROM AUTHOR]

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 FROM AUTHOR]

ABSTRACT The northern bobwhite ( Colinus virginianus; hereafter, bobwhite) population decline has prompted several studies over the past decade investigating bobwhite population genetics and overall connectivity. The zeitgeist of current quail conservation is that bobwhite populations have become increasingly fragmented, leading to their decline as a result of reduced fitness associated with effects from small population size. A few studies exploring population-level patterns of genetic connectivity at the local scale have identified some areas possessing limited gene flow likely due to recent anthropogenic landscape changes. Interestingly, however, multiple studies using genetic methods have also suggested that the species has experienced a recent range-wide expansion with few barriers to dispersal, suggesting a large panmictic population. Although the above are both supported by empirical data, we highlight another possibility that has been proposed yet rarely investigated. Millions of wild bobwhites have been transported among populations, and millions more captive-reared bobwhites have been and continue to be released across the species' range. Given the massive scale at which bobwhites have been artificially dispersed, more research is needed to investigate the effects of introgression of nonlocal birds on our ability to understand recent changes in bobwhite population fragmentation, size, and diversity. Such information has important management implications to long-term bobwhite population sustainability. By quantifying the level of human-mediated bobwhite dispersal events, our review cautions against assigning evolutionary or conservation significance to patterns of genetic connectivity among bobwhite populations until a more systematic effort is made to verify that such activities have not affected our ability to identify natural gene-flow patterns at both local and broad-scale distributions. © 2017 The Wildlife Society. [ABSTRACT FROM AUTHOR]

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 FROM AUTHOR]

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 FROM AUTHOR]

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 FROM AUTHOR]

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 FROM AUTHOR]

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 FROM AUTHOR]

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 FROM AUTHOR]

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 FROM AUTHOR]

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. Despite high levels of mortality, wildlife managers and hunters continue to release captive‐reared Galliformes to augment wild populations. Using paired‐release trials we observed a trained Harris's hawk to select a captive‐reared northern bobwhite over a wild northern bobwhite in 8 of 10 trials, potentially indicating that avian predation is a greater risk for captive‐reared birds than wild birds. [ABSTRACT FROM AUTHOR]

ABSTRACT Conservation practices are designed to provide habitat conditions that meet the environmental requirements for species of conservation concern. However, exotic invasive grass species may reduce the efficacy of these practices because they disrupt biological processes. During 7 August-6 September 2001, we investigated 2 possible ecological impacts of bermudagrass ( Cynodon dactylon) on northern bobwhite ( Colinus virginianus) brood ecology in managed field margins (Laurens County, GA, USA)-reduction in mobility and increased thermal risk. We tested and compared movement rates using imprinted chicks as assays and the thermal environment using in situ temperature probes for bermudagrass and forb habitats. Furthermore, we built upon the existing thermal ecology of northern bobwhite literature and established thermal models to derive time-to-death values from our empirical data. Bermudagrass reduced movement times for chicks 5-days old (0.45 min slower in treatments with bermudagrass), but not for chicks 10-days old. Furthermore, temperatures reached higher daytime temperatures in bermudagrass plots (44.0° C vs. 40.1° C) and crossed the critical hyperthermia threshold more often (32% vs. 11%) than in forb-dominated habitats. Based on simulations, chicks would reach thermal death much earlier in bermudagrass regardless of age. Collectively, our results suggest that bermudagrass reduces habitat quality for bobwhites through reduced movement efficiency and increased thermal stress. Large-scale reductions in bermudagrass are unlikely because of its invasive nature and economic importance to agriculture. However, targeted control or suppression of bermudagrass prior to and following field fallowing is necessary to achieve the objectives of conservation programs for bobwhites and likely other ground-dwelling birds. © 2015 The Wildlife Society. [ABSTRACT FROM AUTHOR]

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 FROM AUTHOR]

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 FROM AUTHOR]

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 < 0.010). However, we documented no change in the amount of woody cover used by bobwhites in their home range between the raptor migration (6.6% ± 0.5%; n = 73 bobwhites) and non-migration periods (7.1% ± 0.4%; n = 105 bobwhites; P = 0.490). In addition, bobwhites that survived the raptor migration period used similar amounts of woody cover within their home range (6.3% ± 0.6%, n = 58 bobwhites) compared with those dying during the migration period (6.8% ± 0.4%, n = 100 bobwhites; P = 0.530). Our data suggest that bobwhites do not alter their use of woody cover at the home-range scale in response to increasing raptor abundance, but this does not preclude increased use of woody cover at the point-of-use scale. © 2014 The Wildlife Society. [ABSTRACT FROM AUTHOR]

ABSTRACT In response to the decline of northern bobwhite ( Colinus virginianus; hereafter, bobwhite) in eastern Oklahoma, USA, a cost-share incentive program for private landowners was initiated to restore early successional habitat. Our objectives were to determine whether the program had an effect on bobwhite occupancy in the restoration areas and evaluate how local- and landscape-level habitat characteristics affect occupancy in both restoration and control areas. We surveyed 14 sample units that received treatment between 2009 and 2011, and 17 sample units that were controls. We used single-season occupancy models, with year as a dummy variable, to test for an effect of restoration treatment and habitat variables on occupancy. We found no significant treatment effect. Model selection showed that occupancy was best explained by the combination of overstory canopy cover and habitat area at both the local and landscape scales. Moran's I revealed positive spatial autocorrelation in the 1,000-3,000-m distance band, indicating that the likelihood of bobwhite occupancy increased with proximity to other populations. We show that creating ≥20 ha of habitat within 1-3 km of existing bobwhite populations increases the chance of restoration being successful. © 2013 The Wildlife Society. Published 2013. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

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 FROM AUTHOR]

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; ${\bar {x}}$ ± 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 < 20%). Perpendicular-distance error slightly increased with target distance (0.7-m increase in error for every 10-m increase in target distance). Overall, the electronic system appears to be a promising technique to estimate density of northern bobwhite and possibly other terrestrial species for which aerial-based distance sampling is appropriate. © The Wildlife Society, 2012 [ABSTRACT FROM AUTHOR]

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 < 0.001). Translocated bobwhites also had larger home ranges ( ${\bar {x}}$ = 398.1 ha; n = 55 bobwhites) than resident bobwhites ( ${\bar {x}}$ = 10.9 ha; n = 28 bobwhites; P = 0.003). Moreover, percent of hens nesting (95% CI = 36 ± 16.4%) and nesting rate (95% CI = 1.1 ± 0.2 nests/hen) were lower for translocated bobwhites than for resident bobwhites (79 ± 12.4% and 1.6 ± 0.3 nests/hen, respectively). Our restoration efforts were unsuccessful; relative abundance of bobwhites remained low (≤1.0 covey heard/point) on translocation sites despite intensive translocation efforts. Restoring bobwhite populations in areas with few remaining bobwhites may be beyond the realm of practical management in this fragmented ecoregion. © 2012 The Wildlife Society [ABSTRACT FROM AUTHOR]

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 FROM AUTHOR]

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 FROM AUTHOR]

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 FROM AUTHOR]

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 FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]