1398 BOBWHITE RESPONSE TO MANAGEMENT PRACTICES Assessments of northern bobwhite ( Colinus vir- ginianus ) (hereafter, bobwhite) populations in the Southeast consider habitat loss resulting from changing land-use practices to be causal to recent declines (Brennan 1991, Sauer et al. 2000). On rural landscapes modern farming and silvicultural sys- tems limit amounts of suitable nesting, brood-rear- ing, and winter habitat (Brennan 1991, Burger et al. Wildlife Society Bulletin 2005, 33(4):1398–1405 Peer refereed Address for William E. Palmer: Tall Timbers Research Station, 13093 Henry Beadel Dr., Tallahassee, FL 32312, USA; e-mail: bill@ttrs.org. Address for Shane D. Wellendorf, James R. Gillis, and Peter T. Bromley: Fisheries and Wildlife Sciences Program, North Carolina State University, Raleigh, NC 27695-7646, USA; present address for Wellendorf: 13093 Henry Beadel Dr., Talla- hassee, FL 32312, USA; present address for Gillis: USDA - NRCS, 122 Pleasant Acres Rd, York, PA 17402, USA; present address for Bromley: 871 Barnes Road, Eden, NC 27288, USA. Effect of field borders and nest- predator reduction on abundance of northern bobwhites William E. Palmer, Shane D. Wellendorf, James R. Gillis, and Peter T. Bromley Abstract Fallow-field borders along edges of crop fields have been promoted for increasing north- ern bobwhites ( Colinus virginianus ) on farms and are a component of recovery plans for this species. However, research on bobwhite population response to field-border prac- tices is sparse. Previous research on 2 farms documented increased use of farm fields and greater reproduction by bobwhites on farms with field borders, but nesting success was low during May and June. Bobwhite population response to field-border practices may increase when they are combined with nest-predator reduction on farms. Effect of nest- predator reduction on bobwhite populations on farmed landscapes has not been investi- gated in the Southeast. Therefore, we tested the effects of field borders and mesomam- mal nest-predator reduction on bobwhite abundance on 12 farms in eastern North Carolina, 1997–1999. We applied treatments to farms as factorial combinations. Reduction of mesomammal nest predators, including raccoons ( Procyon lotor ), Virginia opossums ( Didelphis virginiana ), and foxes ( Urocyon cinereoargenteus and Vulpes vulpes ), occurred from February–May of each year. To assess bobwhite response to treat- ments, we measured summer abundance of males using variable-radius point counts and covey abundance on farms in September and October using morning covey-call surveys. Bobwhites were more abundant on farms with field borders during summer ( P =0.08). On field-border farms we heard 1.8 × the number of coveys heard on farms without field bor- ders ( P = 0.004). Summer abundance of bobwhites did not differ as a result of predator reductions ( P =0.37), and we heard slightly fewer coveys on predator-reduction farms ( P =0.084) during autumn. However, we heard more coveys on farms with both field bor- ders and predator reduction compared to all other farms ( P =0.022). Field-border systems were a practical management technique to increase autumn abundance of bobwhites on individual farms in eastern North Carolina. Key words abundance, call counts, Colinus virginianus , farm, field borders, nest predator, North Carolina, northern bobwhite Palmer et al (Gene).qxp 3/7/2006 3:59 AM Page 1398 1995, Puckett et al. 1995, Palmer et al. 2001). Solutions to these habitat deficiencies are needed to recover bobwhite populations. The potential of managing field edges for farm- land wildlife has been recognized for many years (Davison 1941, Dambach 1945), and their value as habitat for gray partridge ( Perdix perdix ) in Britain (Rands and Sotherton 1987) and pheasants ( Phasinus colchicus ) in the midwestern United States (Best et al. 1995) has been intensively stud- ied. Strips of vegetation on edges of crop fields (hereafter, field borders) have been promoted by federal and state conservation programs to reduce translocation of sediment, nutrients, and pesticides and also to enhance fish and wildlife habitat (Natural Resource Conservation Service 1999). Field borders have become an important compo- nent of restoration plans (e.g., Northern Bobwhite Conservation Initiative, hereafter NBCI) for bob- white populations on agricultural areas throughout the Southeast (Dimmick et al. 2001). Field borders are potentially attractive to farmers because they are established on less productive portions of fields (Morris 1998) and present little risk to crop pro- ductivity (Boatman and Sotherton 1988, Outward et al. 2000). Despite the promotion of field borders, research on the response of bobwhite populations is limit- ed. Puckett et al. (1995) found that bobwhites were more abundant during spring on 2 farms with field borders than paired farms without. In their study bobwhites on field-border farms produced more nests and had greater chick production than bob- whites on farms without borders. Given the poten- tial importance of field borders in conservation plans for bobwhites, additional research on bob- white population response is warranted. When suitable nesting habitat is limited, nests in established habitats, such as field borders, may be particularly vulnerable to predation (Camp and Best 1994, Greenwood et al. 1995). Puckett et al. (1995) reported low nesting success of bobwhite nests on farms with field borders prior to July but higher nesting success later (Puckett et al. 1995). Mesomammal predators are the most important group of nest predators for bobwhites (Fies and Puckett 2000, Staller et al. 2005), and these preda- tors are potentially abundant on agricultural land- scapes (Miller and Leopold 1992). Local reduction of these nest-predator populations in conjunction with habitat improvements may improve reproduc- tive success and autumn populations of bobwhites (Côté and Sutherland 1997, Rollins and Carroll 2001). In addition to the biological realities of pre- dation and bobwhite populations, many farmers and rural citizens consider predators to be a more important problem facing bobwhite managers than habitat, which may thwart efforts to implement habitat management programs (Rollins and Carroll 2001). In this study we tested the efficacy of field borders and mesomammal nest-predator reduction for increasing bobwhite abundance on typical farms in 2 regions of eastern North Carolina with different farm landscape configurations. Study areas We studied bobwhite response to field borders and mesomammal reduction on farms in Hyde, Tyrrell, and Wilson counties, North Carolina (1997–1999). Within each county we selected 4 farms spaced at least 1.7 km apart for study. In Wilson County, located in the upper coastal plain, study farms averaged 250 ha and contained an aver- age of 39 irregularly shaped fields averaging 1.8 ha in size. Tilled fields comprised 43% of farms. Crop types (soybeans, corn, cotton, wheat, and tobacco) were similar among farms but varied in prevalence among years (P. Bromley, unpublished data). Timber stands of various ages were interspersed among crop fields. Hyde and Tyrrell counties were located in the lower coastal plain. Farms were composed of drained wetlands with organic soils and were typi- cal of large “ditch-to-ditch” commercial agriculture. Farms consisted of flat, uniformly rectangular 8-ha fields that covered several thousand hectares. Each field was bordered by drainage ditches along the sides and canals or farm roads bordering the ends. We chose portions of these large farms averaging 202 ha ( n =16–25 fields) as study areas. Corn, soy- beans, or winter wheat, followed with soybeans, were planted over large areas usually covering an entire farm block. Methods Experimental design We randomly applied 2 × 2 factorial treatment combinations to each farm within each county. Treatments consisted of field borders at the edges of all tilled fields, predator reduction, combination of field borders and predator reduction, or control without either treatment. Bobwhite response to management practices • Palmer et al. 1399 Palmer et al (Gene).qxp 3/7/2006 3:59 AM Page 1399 19385463, 2005, 4, Downloaded from https://onlinelibrary.wiley.com/doi/10.2193/0091-7648(2005)33[1398:EOFBAN]2.0.CO;2 by University Of Florida, Wiley Online Library on [13/03/2026]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License Field borders Field borders consisted of 3–5-m strips of native herbaceous vegetation along field edges. Field bor- ders were established in the spring of 1996 in Wilson and Hyde counties and in the spring of 1997 in Tyrrell County. The field borders comprised 13% of tilled land in Wilson County, 12% of tilled land in Tyrrell County, and 9% in Hyde County. Field border vegetation was dominated (average >5% cover) by goldenrods ( Solidago spp.), giant cane ( Arundinaria gigantea ), blackberry ( Rubus argutus ), lespedezas ( Lespedeza spp.), wax myrtle ( Myrica cerifera ), and dog fennel ( Eupatorium capillifolium ). Woody vegetation was controlled in field borders annually using a selective herbicide application (Warson et al. 1998) or by physical removal. On farms without field borders, fields were managed normally, with crops planted to the outside edge of fields, and all noncrop vegetation in field edges was mowed each winter. Mesomammal predator reduction We trapped mesomammals, including red foxes ( Vulpes vulpes ), gray foxes ( Urocyon cinereoar- genteus ), raccoons ( Procyon lotor ), and Virginia opossums ( Didelphis virginiana ) (hereafter, target predators), on selected farms from February–May, 1997–1999. The goal of trapping was to reduce predator numbers during the early nesting period when nesting was thought to be most impacted by predators (Puckett et al. 1995). Trapping effort was consistent among sites. One technician trapped each farm receiving predator reduction for 17 con- secutive days using 40 traps per night. We used 3 types of traps: 30.5 × 30.5 × 91.4-cm cage traps (Tomahawk Live Trap Co.,Tomahawk,Wisc.),Victor soft-catch 1½ foothold traps (Woodstream Corp., Lititz, Penn.), and nylon egg traps (Egg Trapp Co. Inc, Ackley, Ia.) (added in 1998). Technicians main- tained 10 cage traps, with foothold traps split approximately equally between egg traps and foothold traps. We anesthetized captured predators with Telazol ® (Fort Dodge Laboratories, Fort Dodge, Ia.) and euthanized target predators by an intracardial injection of Beuthanasia ® (Veterinary Laboratories, Lenexa, Kans.). We froze carcasses and delivered them to the North Carolina State University College of Veterinary Medicine for additional study. Target predator activity In 1998 and 1999 we indexed predator activity using an artificial nest system. The artificial nests were made of wire mesh and covered with camou- flaged material and were approximately the size of a bobwhite nest. We placed 6 bobwhite eggs inside the artificial nest as a scenting agent and placed a 1- m ring of sand around each nest as a tracking sub- strate. The sand ring was a mixture of sand, miner- al oil, and Crayola (Binney & Smith, Inc., Easton, Pa.) powdered paint to match background soil color. We recorded animals that visited artificial nests by identifying their tracks left in the sand ring. Monthly activity surveys consisted of ran- domly placing 20 artificial nests per farm (80 nests per county). To do so we randomly chose 20 fields and plotted random azimuths from field centers. The artificial nests were located either at the inter- section of the random azimuth and the field edge or on the random azimuth, within 5 m from the field edge. We monitored nests for 4 days or until all eggs were taken from the nest. We conducted sur- veys once before trapping started and immediately after each trapping period was completed. Summer point counts To estimate relative abundance of bobwhites on farms during the breeding season, we conducted whistling-male-bobwhite call counts in May and June, 1997, 1998, and 1999 (Freemark and Rogers 1995). We placed 4 to 6 stations at each farm. We spaced stations >250 m apart in Wilson County and >350 m apart in the more open habitats of Hyde and Tyrrell counties. Four observers simultaneous- ly surveyed all farms within a county. Surveys began 15 minutes before sunrise. After arriving at the survey station, we waited for a 1-minute accli- mation period and then, over the next 7 minutes, we recorded the number of whistling males heard. We did not survey if wind was >15 km per hour or if there was any precipitation (Robel et al. 1969). Covey-call counts We used early morning covey-call surveys to measure autumn covey abundance (Wellendorf et al. 2004) on the farms. We counted coveys that called during the 45 minutes before sunrise from 2 survey points at each farm. Survey points were >500 m apart to avoid double-counting calling cov- eys. We centered survey points in crop fields and at least 100 m from adjacent wood edges. We con- ducted surveys on 2 consecutive mornings. We used 8 observers each morning to simultaneously survey all farms within a county. We conducted sur- 1400 Wildlife Society Bulletin 2005, 33(4):1398–1405 Palmer et al (Gene).qxp 3/7/2006 3:59 AM Page 1400 19385463, 2005, 4, Downloaded from https://onlinelibrary.wiley.com/doi/10.2193/0091-7648(2005)33[1398:EOFBAN]2.0.CO;2 by University Of Florida, Wiley Online Library on [13/03/2026]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License veys between the last week of September and the end of October, prior to crop harvest and while coveys were located in or near crop fields (Wellendorf et al. 2002). Weather guidelines were the same as summer point-count surveys. Data analysis Target predator activity . We determined target predator visitation rates by dividing total number of documented target predator visitations by total number of available nest-nights during a survey period. Available nest-nights included all nest-days, except those where the sand ring was made unus- able by rain or other disturbances. We summarized data into pretrap and trapping categories for analy- sis. We averaged monthly activity rates during the trapping period to give a yearly estimate of preda- tor activity. We used repeated-measures MANOVA and generalized linear modeling procedures to test predictions about the effects of field borders and predator removal on mesomammal predator visita- tion rates over years (PROC GLM, SAS Institute, Inc. 1998). We transformed visitation rates using the square root transformation to meet assumptions of MANOVA (Ramsey and Schafer 1997). Bobwhite abundance We adjusted autumn covey-call counts by dividing each call-count obser- vation by a predicted covey-call rate, which adjusts calling rate of coveys for effects of covey density, weather, and seasonal timing (Wellendorf et al. 2004). Covey-calling rates and predicted covey-call rates are lower at low covey density. Therefore, when few coveys are heard per point, the covey abundance index is inflated. At relatively high covey counts, calling rate tends to be higher, result- ing in a minor adjustment to the count. Summer bobwhite call surveys were not adjusted because we did not have prediction models of calling prob- ability for males during summer. We considered each survey point a subsample and considered each farm the sampling unit. Therefore, we averaged subsample counts collected on a farm within each season to produce 2 separate seasonal indices of bobwhite abundance, 1 for sum- mer and 1 for autumn. We tested these abundance indices for normality and used Levene’s test to determine whether homogeneity of variance assumptions was met (Ramsey and Schafer 1997). We log-transformed the adjusted covey-call counts, the autumn index of bobwhite abundance, to meet normality assumptions. We examined comparisons between treatments, counties, and years using repeated measures MANOVA (PROC GLM, SAS; SAS Institute, Inc. 1998). Results Target predator removal We removed 235, 229, and 292 target predators from study farms, 1997–1999, respectively. Mean number of target predators removed annually at Hyde, Tyrrell, and Wilson county farms with field borders was 50.0 (SE = 12.2), 54.7 (SE = 6.4), and 42.0 (SE=2.3), respectively. Mean number of target predators annually removed at Hyde, Tyrrell, and Wilson county farms without field borders was 25.7 (SE=5.8), 32.0, SE=8.5), and 47.7 (SE=4.3). Target predator activity Pretrapping target predator activity in 1999 ( x - = 0.14, SE = 0.042) was similar to 1998 ( x -= 0.13, SE = 0.046) and was consistent for counties ( F 2,2 =6.53, P =0.133), field-border farms ( F 1,2 =3.14, P =0.218), and predator-reduction farms ( F 1,2 = 6.63, P = 0.124). During trapping periods target predator activity on predator-reduction farms ( x -=0.026, SE= 0.005) remained lower than on farms without trap- ping ( x -=0.106, SE=3.4); ( F 1,7 =7.63, P =0.028). This outcome differed by county ( F 2,7 =6.22, P =0.028), however, with Wilson having the largest difference in target predator activity between predator reduc- tion treatments. Bobwhite response Summer bobwhite abundance in Hyde ( x -=1.9, SE = 0.24) and Tyrrell ( x - = 2.2, SE = 0.21) counties was slightly greater than in Wilson county ( x - = 1.2, SE = 0.12); ( F 2,2 =10.28, P =0.08). Summer abundance of bobwhites was slightly greater on field-border farms ( x - = 2.1, SE = 0.26) than farms without field borders ( x - = 1.5, SE = 0.15; F 1,2 = 11.08, P = 0.08). Summer abundance of bobwhites was not different on farms receiving predator reduction ( x -=1.9, SE= 0.28) than farms not trapped ( x -=1.7, SE=0.20; F 1,2 = 11.08, P = 0.37). There was a minor year effect with a decrease in summer bobwhite abundance in 1999 ( x -=1.4, SE=0.17) relative to 1997 ( x -=2.0, SE= 0.21) and 1998 ( x - = 1.9, SE = 0.23; F 2,4 = 4.82, P = 0.09). Similar to summer bobwhite call counts, number of coveys heard per point was greater on lower coastal plain farms ( F 2,2 = 212.6, P = 0.005), with a mean of 5.2 (SE = 0.72) coveys heard in Tyrrell County, 4.9 (SE=0.32) at Hyde County, and 2.6 (SE Bobwhite response to management practices • Palmer et al. 1401 Palmer et al (Gene).qxp 3/7/2006 3:59 AM Page 1401 19385463, 2005, 4, Downloaded from https://onlinelibrary.wiley.com/doi/10.2193/0091-7648(2005)33[1398:EOFBAN]2.0.CO;2 by University Of Florida, Wiley Online Library on [13/03/2026]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License =0.42) at Wilson County. We heard more coveys on farms with field borders than those without field borders ( F 1,2 = 216.0, P = 0.005) (Table 1). Over all farms and years, we heard 5.5 (SE=0.46) coveys per point on farms with field borders versus 3.4 (SE = 0.46) coveys per point on farms without field bor- ders. There was no difference in number of coveys heard on farms with predator reduction relative to farms where predators were not trapped ( F 1,2 = 10.4, P =0.084). Although predator reduction alone had no effect, farms with both field border and predator reduction had more coveys detected than all other farms ( F 1,2 =43.3, P =0.022) (Figure 1). On average, we heard 5.6 (SE = 0.71) coveys per point on sites with both borders and predator reduction, versus 4.5 (SE=0.55) coveys per point on sites with just field borders. This compares to 3.2 (SE=0.61) and 3.6 (SE = 0.72) coveys per point for sites with predator removal only or reference sites, respec- tively. Discussion We observed greater abundance of bobwhites during autumn on farms with field borders across all counties and years. Greater abundance was pre- sumably a result of increased use of farms with field borders during spring and summer, which resulted in greater chick production on those farms. However, because we did not radiomark bobwhites in this study, the mechanisms causing greater autumn abundance on field-border farms were not known. On farms in Dare County, which borders Tyrrell County, Puckett et al. (2000) documented that bobwhites moved onto field-border farms ear- lier, established breeding-season home ranges earli- er, and maintained higher overall abundance during the breeding season as compared to paired farms without field borders. Additionally, Puckett et al. (1995) found bobwhite nest incubation rates aver- aged 2.5 times greater on farms with field borders, partially a result of increased rates of nesting earli- er in the summer. We surveyed bobwhite abun- dance on study farms during early autumn, immedi- ately after the breeding season but prior to crop harvest, after which bobwhites on our study sites moved off farms to their winter ranges (Wellendorf et al. 2002). Based on our data and that of Puckett et al. (1995, 2000), we believe our estimates of bob- white abundance during early autumn were repre- sentative of differences in recruitment on our study farms. The numbers of mesomammal nest predators removed each year was similar. The relatively small areas trapped, which approximated typical North Carolina farmland ownership (Morris 1998), likely facilitated resettlement of predators on trapped areas (Chesness et al. 1968, Greenwood 1986). No change in populations of mesomammal predators the year following trapping is a common result of predator-removal studies (Newton 1993, Reynolds and Tapper 1996, Côté and Sutherland 1997). However, we observed a short-term reduction in target predator activity during the trapping period, which accomplished our study objective to reduce potential predation pressure during the early nest- ing season for bobwhites. Temporary reduction of predator activity by trapping has been documented in other studies (Duebbert and Kantrud 1974, Duebbert and Lokemoen 1980, Anthony et al. 1991). Mesomammal predator reduction by itself did not have any effect on post-breeding bobwhite 1402 Wildlife Society Bulletin 2005, 33(4):1398–1405 Figure 1. Interaction of mesomammal predator reduction and fallow-field borders around farm fields on northern bobwhite covey abundance on farms ( n =12), in Hyde, Tyrrell, and Wilson counties, North Carolina, 1997–1999. Table 1. Mean adjusted counts of northern bobwhite coveys heard during covey-call surveys on farms ( n = 12) with and without field borders and mesomammal predator reduction in Hyde, Tyrrell, and Wilson counties, North Carolina, 1997–1999. Raw covey counts were adjusted by dividing by an estimated call rate. Year 1997 1998 1999 Treatment Mean SE Mean SE Mean SE Neither 2.9 1.22 4.8 1.68 3.1 0.91 Predator reduction 2.4 1.28 3.4 0.61 3.9 1.40 Field borders 3.2 0.60 6.0 0.53 4.4 1.04 Both 4.6 0.88 6.4 1.20 5.8 1.73 Palmer et al (Gene).qxp 3/7/2006 3:59 AM Page 1402 19385463, 2005, 4, Downloaded from https://onlinelibrary.wiley.com/doi/10.2193/0091-7648(2005)33[1398:EOFBAN]2.0.CO;2 by University Of Florida, Wiley Online Library on [13/03/2026]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License abundance, even though predator activity was reduced during the nesting season. Bobwhites may not have responded to predator reductions on farms because the farms lacked habitat to attract bobwhites in the first place. This result was sup- ported by the lower counts of bobwhites on farms without field borders and by previous telemetry studies (Puckett et al. 1995, Palmer et al. 1998). Alternatively, bobwhites may not have responded to reduction of mesomammal predators because other nest predators, such as snakes (e.g., Elaphe spp.) and bobcats ( Lynx rufus ), may have compen- sated for the reduction in part of the mesomammal predator community (Rollins and Carroll 2001, Staller et al. 2005). Although no other studies have investigated the effects of predator reduction on bobwhite abundance in the Southeast, studies con- ducted in Texas (Beasom 1974, Guthery and Beasom 1977) reported mixed results. Beasom (1974) observed higher bobwhite reproductive parameters on 2,300-ha predator-control sites in southern Texas. Guthery and Beasom (1977) recorded no change in bobwhite abundance on a 1,500-ha predator-control area in southern Texas, but concluded that predator control allowed for bobwhites to maintain abundance levels during poor habitat and weather conditions. Regardless of the biological reasoning for a lack in response to predator reduction on farms, predator reduction alone was not effective at increasing bobwhite cov- eys on small farms. One rationale for testing the effects of nest-pred- ator reduction on bobwhite populations on farms was earlier research documenting low success of nests located in linear strips such as field borders (Puckett et al. 1995). When suitable nesting habitat is limited, nests in remaining habitats may be par- ticularly vulnerable to predation (Camp and Best 1994, Greenwood et al. 1995). In this context reduction of predator activity on farms had a posi- tive effect on autumn covey abundance. To clarify, predator reduction appeared to increase the effect field-border treatments had on post-breeding abun- dance of bobwhites. However, as with field borders alone, predator reduction along with field borders did not lead to annual incremental increases in bob- white abundance on farms, but rather a greater abundance that was similar each year. Although we observed a mean 1.8-fold increase in autumn bobwhite abundance on field-border farms, bobwhite populations did not continue to increase each year of the study. We believe this was a result of poor habitat for bobwhites across the majority of the farmed landscape. Forests sur- rounding crop fields were closed-canopied, pine ( Pinus spp.)–hardwood forests, hardwood drains, or planted pine plantations, all of which provided marginal bobwhite habitat (Stoddard 1931). On our study farms in Wilson and Tyrrell counties, we documented low survival of radiotagged bobwhites after they emigrated from crop fields to forested habitats (S. D. Wellendorf, unpublished data). We believe that modest population gains from improved recruitment on farms with field borders, or field borders along with temporary nest-preda- tor reduction, were offset by low survival of bob- whites during autumn, winter, and early spring as a result of the low suitability of habitats across most of the farmed landscape. Field borders resulted in increased bobwhite abundance on farms, and therefore including field borders as a management option in regional recov- ery plans is valid. However, enhancing bobwhite populations beyond the levels found in this study likely will result only from habitat improvements across the farmed landscape, such as thinning and prescribed burning of forests to promote suitable year-round habitat for bobwhites. Reduction of mesomammal nest predators increased bobwhite abundance on farms with field borders, but popu- lation improvements were not sufficient to warrant the costs of predator trapping. Further, the low suitability of most habitats on farms for bobwhites likely canceled the potential for predator reduction to have a population effect. This suggests that pred- ator removal as a technique to increase bobwhite populations should be considered only after suffi- cient habitat improvements are in place. Acknowledgments. We thank J. Marcus, M. Lane, R. Outward, and many technicians and interns for assistance with data collection. C. Jernigan, P. Keyser, and M. Gibbs assisted with finding study areas. Many private landowners and managers granted us access to their land including M. Langley, G. Smith, and W. Doughtry. Significant logistical sup- port was provided by D. Baumbarger, C. Betsill, S. Capel, S. Dunston, M. Fies, M. Jones, M. Puckett, T. Sharpe, E. Stanford, and M. Stoskoph. Trapping and handling were done in accordance with NCSU IACUC Agreement #97-004. 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See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License Bobwhite response to management practices • Palmer et al. 1405 nests. Journal of Wildlife Management 69: 124–132. S TODDARD , H. L. 1931. The bobwhite quail: its habits, preserva- tion and increase. Third edition. Charles Scribner’s Sons, New York, New York, USA. W ARSON , B. E,W. E. P ALMER , P.T. B ROMLEY , AND J. R.A NDERSON 1998. Maintaining early-successional habitats using a metal wick applicator. Southeastern Association of Fisheries and Wildlife Agencies Annual Conference 52: 265–273. W ELLENDORF , S. D., W. E. P ALMER , AND P. T. B ROMLEY 2002. Habitat selection of northern bobwhite coveys on two intensive agri- cultural landscapes in eastern North Carolina. Proceedings of the National Quail Symposium 5: 191. W ELLENDORF , S. D.,W. E. P ALMER , AND P.T. B ROMLEY . 2004. Estimating calling rates of northern bobwhite coveys and measuring abundance. Journal of Wildlife Management 68: 672–682. Bill Palmer has been the Director of Game Bird Research and Management at Tall Timbers Research Station since 1996. He received his B.S. from Virginia Tech, his M.S. from Mississippi State University, and his Ph.D. from North Carolina State University. His research interests include northern bobwhite habitat management, behavioral ecology, and population dynamics with an emphasis on predator–prey relationships. Shane Wellendorf has been a wildlife biologist at Tall Timbers Research Station since 2000. He received his B.S. in fisheries and wildlife biology from Iowa State University and his M.S. in fisheries and wildlife science from North Carolina State University. While at N.C. State, he developed a new technique for measuring autumn abundance of quail. Jim Gillis earned a B.S. from Pennsylvania State University and an M.S. from North Carolina State University. His work and interests have focused on mammalian predators. Jim currently is a biologist with the Natural Resources Conservation Service. Pete Bromley is a retired professor of wildlife science at North Carolina State University and a Certified Wildlife Biologist. He led the wildlife–agriculture research/extension program at NCSU for 12 years. Pete is past president of the Virginia and North Carolina chapters of TWS. Associate editor: Applegate Palmer et al (Gene).qxp 3/7/2006 3:59 AM Page 1405 19385463, 2005, 4, Downloaded from https://onlinelibrary.wiley.com/doi/10.2193/0091-7648(2005)33[1398:EOFBAN]2.0.CO;2 by University Of Florida, Wiley Online Library on [13/03/2026]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License