Eric W. Kurzejeski

Conservation Reserve Program: Source or Sink Habitat for Grassland Birds in Missouri?

The Conservation Reserve Program (CRP) has been eredited with contributing substantially to the conservation of grassland birds. Although many species have nested in grasslands established under the CRP, little evidence of positive effect on populations has been reported. We measured reproductive rates and estimated fecundity of 7 grassland bird species in CRP fields in northern Missouri and compared those rates to estimates of fecundity needed to maintain stable populations (λ = 1). Under conservative assumptions of survival, CRP fields seemingly were source habitats (fecundity exceeded levels necessary for λ = 1) for grasshopper sparrows (Ammodramus savannarum) and field sparrows (Spizella pusilla) in at least 2 of 3 years (1993: P = 0.02, 1995: P < 0.001) and pooled over 3 years (Ps < 0.001). Although evidence was less compelling, CRP fields were likely source habitat for eastern meadowlarks (Sturnella magna) and American goldfinches (Carduelis tristis). For American goldfinches, fecundity was greater than that necessary for λ = 1 in 1995 (P < 0.001), and pooled over 3 years (P < 0.001). Our pooled estimate of fecundity was greater than necessary for λ = 1 for eastern meadowlarks (Ps < 0.001), but only under a liberal assumption of survival in 2 of 3 years (1993: P = 0.001; 1995: P = 0.088). Fecundity of common yellowthroats (Geothlypis trichas) varied substantially; therefore, source-sink status alternated among years, although the pooled estimate of fecundity was less than required for λ = 1 (P < 0.001). Dickcissel (Spiza americano) fecundity was consistently less than necessary for λ = 1 (conservative survival assumption: all Ps < 0.001; liberal survival assumption: 1994 P - 0.008. pooled P = 0.014). For red-winged blackbirds (Agelaius phoeniceus), CRP fields were consistently a sink habitat (all Ps < 0.001). Based on our evidence, the CRP likely has contributed to the conservation of grasshopper sparrows, field sparrows. and eastern meadowlarks. Although large numbers of dickcissels and red-winged black-birds nested in CRP fields, there is little evidence that the CRP has contributed to populations of those species.

Grassland Bird Conservation: CP1 vs. CP2 Plantings in Conservation Reserve Program Fields in Missouri

Abstract To determine the relative value of different Conservation Reserve Program (CRP) plantings for breeding grassland and winter birds we measured vegetation structure, avian abundance and reproductive success, and estimated fecundity during 1993–1995 on CP1 (cool-season grass) and CP2 (warm-season grass) plantings in 16 fields in northern Missouri. CP1 fields had been planted to cool-season grasses or cool-season grass-legume mixtures and CP2 fields had been seeded with switchgrass (Panicum virgatum). Species richness, abundance and nesting success of grassland birds during the breeding season and total bird use in the winter did not differ between CPs. During the breeding season CP1 fields had higher abundances of grasshopper sparrow (Ammodramus savannarum), eastern meadowlark (Sturnella magna), Henslows sparrow (Ammodramus henslowii) and American goldfinches (Carduelis tristis), whereas common yellowthroats (Geothlypis trichas) were more abundant in CP2 fields. Fecundity of dickcissels (Spiza americana) and nesting success and fecundity of red-winged blackbirds (Agelaius phoeniceus) were higher on CP2 than on CP1 habitat, but both CPs were likely sinks (λ < 1) for these species. Both CPs were likely source (λ > 1) habitat for grasshopper sparrows, whereas only CP1 habitat was likely a source for eastern meadowlarks and American goldfinches. In winter American goldfinches were more abundant in CP1 fields than CP2 fields. The shorter, more diverse, cool-season grass fields were equal or better habitat than taller, more vertically dense, switchgrass-dominated fields for grassland birds, including several species of high conservation concern. Single-species plantings of warm- or cool-season grasses should be avoided to increase the potential wildlife benefits of CRP and other grassland habitats.

Reproductive strategies, success, and mating systems of northern bobwhite in Missouri

To better understand the reproductive mechanisms that enable northern bobwhite (Colinus virginianus) to recover from high annual mortality, we studied the reproductive strategies, success, and mating systems of 321 radio-marked bobwhite in northern Missouri during 1990-92. Seventy-four female and 43 male bobwhite incubated 159 nests. Females exhibited apparent monogamy during 60% of nesting attempts and apparent polyandry during 40%. Over the entire nesting season, 71% of females were polyandrous. Of those birds alive 15 April (n = 112 F, n = 148 M), 40.2% of females and 13.5% of males successfully hatched ≥1 nest. Seventy-four percent of females (n = 42) and 26% of males (n = 50) surviving until 1 September successfully hatched ≥1 nest. Nesting females that survived the nesting period incubated a mean of 1.8 nests (SE = 0.13), and males incubated 1.0 nests (SE = 0.04). Of those birds that failed on an initial nesting attempt, 57.9% of females (n = 38) and 2 of 23 males incubated ≥1 renest. Of those females that were successful on their initial nesting attempt, 25.7% attempted second nests. Female first nests represented 45.9%, female renests 20.1%, female double-clutch attempts 5.7%, and male-incubated nests 28.3% of all nests located. Nest survival was 43.7% (SE = 3.9). The reproductive system of northern bobwhite enables recovery from low annual survival or periodic catastrophic declines and may be an adaptation to fluctuating resources in ephemeral, dynamic habitats.

Survival and cause-specific mortality of northern bobwhite in Missouri

Efforts to understand fluctuations in northern bobwhite (Colinus virginianus) abundance illustrate inadequate knowledge of demographic processes. Therefore, we estimated seasonal survival, annual survival, and cause-specific mortality of 1,001 radio-marked bobwhite in northern Missouri. Annual survival was 5.3 ± O.5% and did not differ between ages (P = 0.33) or sexes (P = 0.48). Fall-spring survival (15.9 ± 0.8%) was less than spring-fall survival (33.2 ± 2.7%, P < 0.001). Females had lower fall-spring survival (13.7 ± 1.1%) than males (17.6 ± 1.1%, P = 0.02). Male-biased sex ratios likely result from differential fall and winter survival. Avian (28.7%) and mammalian (25.7%) predators were primary natural mortality agents. Hunter-retrieved (22.9%) and -unretrieved (5.3%) kill resulted in 28.2% harvest-related mortality. During springfall, males experienced higher avian mortality (26.5%) than females (20.0%) (P = 0.09). Greater vulnerability of males to avian predators may represent a cost of displaying. Each incubation and brood-rearing attempt reduced survival by 16% when compared with nonreproductively active birds during a similar period. Bobwhites must be highly productive to replace annual population losses

Survival of Wild Turkey Hens in North Missouri

Survival and cause-specific mortality of wild turkey (Meleagris gallopavo silvestris) hens were investigated in north Missouri during 1984-85. Survival estimates and distributions were calculated using the Kaplan-Meier product-limit method from a sample of 60 radio-marked hens. The annual survival rate was 0.435 ? 0.073. Predation and poaching were the major causes of mortality, accounting for 54.9 and 38.7% of the losses, respectively. Legal fall harvest was responsible for only 3.2% of the deaths and was considered a minor cause of mortality. Seasonal losses were highest during spring. Forty-two percent of the illegal hen kills occurred during the spring gobbler season. Survival probabilities with poaching or predation as the only source of mortality followed similar patterns. J. WILDL. MANAGE. 51(1):188-193 Wild turkey populations in the mixed timber-agricultural regions of the Midwest have been reported to exceed 30 birds/km2 of timber (Hanson 1984, Lewis and Kurzejeski 1984). Effective management of these populations requires quantitative data on hen turkey survival. Radio-telemetry data have been used to examine survival in reintroduced turkey populations (Swank et al. 1985), expanding turkey populations (Porter 1978), and indigenous turkey populations in the traditional southern range (Everett et al. 1980, Holbrook and Vaughan 1985). Data on survival rates and causes of turkey mortality are scarce, and estimates of hen wild turkey survival are lacking for established populations in the Midwest. Estimates of hen turkey survival are important in the formulation of fall harvest recommendations and as an indication of reproductive potential. Furthermore, determining seasonal and cause-specific survival provides inference as to the relative importance of natural, illegal, and where appropriate, legal harvest mortality. The objectives of this study were to determine annual and seasonal survival and causes of mortality for hen wild turkeys in north Missouri during March 1984-March 1985. We thank V. L. Kimmel for coordinating and conducting the fieldwork, and E. A. Keyser, J. S. Fleming, D. J. Neuswanger, and B. J. Otten for assistance in trapping turkeys. C. J. Scriven, M. E. Wade, C. Turner, E. R. Jayne, and numerous others provided access to their private lands that was essential in conducting this study. S. R. Winterstein, C. Bunck, and S. L. Sheriff provided assistance with data analyses. Partial funding for this study was provided by the Mo. State Chapter and various local chapters of the Natl. Wild Turkey Fed. This study also was supported, in part, by funds supplied by the Fed. Aid to Wildl. Restor. Act, under PittmanRobertson Proj. W-13-R-38. S. S. Sapp typed drafts of the manuscript. The manuscript was reviewed by K. C. Sadler, O. A. Torgerson, R. W. Cannon, S. R. Winterstein, and L. M. Smith. STUDY AREA AND METHODS Hen wild turkeys were captured, radio instrumented, and released in a 52-km2 area in Adair County, Missouri, about 8 km west of Kirksville. The topography is rolling with elevations ranging from 226 to 297 m. Forested land comprises 59.6% of the area. Agricultural lands comprise the remainder, with 16.2% of the area in row crops and 24.2% in pasture. The timber component is 2nd growth oak (Quercus spp.) and hickory (Carya spp.) predominated by pole-sized stands. The floodplain of the Chariton River, which bisects the study area, contains a majority of the cropland. The upland portions of the area are a mosaic of timber interspersed with pastures and hayfields. Trapping was conducted using cannon nets during 2 periods (1 Aug-15 Oct 1983 and 1 Jan-13 Mar 1984). Hens were aged, radio instrumented, and released at the capture site. Transmitters were attached using a backpack harness. The 140-g radio package included a

Reproductive Parameters of Wild Turkey Hens in North Missouri

Reproductive parameters of eastern wild turkeys (Meleagris gallopavo silvestris) were studied on a 52-km2 area in north Missouri during 1981, 1982, 1984, and 1985. Nest success, hen success, nesting rates, clutch size, fate of nests, and poult mortality were estimated from a sample of 127 radio-instrumented hens. Nesting success and hen success were highly variable among years. Average nest success was 30.6% with hen success averaging 37.8%. Few differences were detected between adult and subadult hens in nest success or hen success. Predation was the major cause of nest losses. Renesting rates averaged 55.0% in 1981, 1982, and 1985; but only 14.0% following a late spring in 1984. Both renesting rate and nesting chronology appeared to be affected by early spring temperatures. Poult mortality averaged 61.9% at 4 weeks post-hatch. Reproductive success in this study was lower than has been reported elsewhere in the subspecies range. J. WILDL. MANAGE. 51(3):535-540 Reproductive parameters of recently reintroduced eastern wild turkey populations have been studied extensively (Eichholz and Marchinton 1975, Little and Varland 1981, Clark 1985, Miller et al. 1985). Reproductive success and nesting ecology also have been examined in indigenous turkey populations in the south (Williams et al. 1968, Hon et al. 1978, Everett et al. 1980, Metzler and Speake 1985, Speake et al. 1985). Porter (1978) investigated reproduction in an established, but rapidly expanding, turkey population in Minnesota, the northern boundary of the eastern wild turkey range. To date no studies have reported reproductive parameters from stable turkey populations in the Midwest. Eastern wild turkey densities in this region of the country are among the highest reported for the species, exceeding 30 birds/ km2 of timber (Kurzejeski et al. 1987). Effective management of these populations requires quantitative estimates of reproductive success and poult mortality. The purpose of this paper is to report reproductive parameters and poult mortality estimates for an established wild turkey population in north Missouri, and to examine the relationship between yearly breeding chronology and temperatures. Assistance was provided by E. A. Keyser, J. S. Fleming, B. J. Otten, D. J. Newswanger, and K. C. Ehlers. E. R. Jayne, C. J. Scriven, M. E. Wade, C. Turner and numerous others provided access to their private lands that was essential in conducting this study. G. S. Olson and S. L. Sheriff assisted with data analyses. Partial funding for this study was provided by the State Chap. and local chapters of the Natl. Wild Turkey Fed., and by the Fed. Aid Wildl. Restor. Act, under Pittman-Robertson Proj. W-13-R. The Wildl. Res. secretarial staff typed drafts of this manuscript. K. C. Sadler reviewed the manuscript. STUDY AREA AND METHODS Wild turkey hens were captured using cannon nets during 4 winters (1980-81, 1981-82, 198384, and 1984-85). Each hen was aged (subad or ad), instrumented, and released at the capture site. A 140-g mortality-sensitive radio package, operating on 164-165 MHz band, was attached using a back-pack harness. The radio package was powered by a lithium battery with an expected life of 24 months. Instrumented hens were monitored daily on a 52-km2 study area about 8 km west of Kirksville in Adair County, Missouri. A more detailed description of the study area can be found in Kurzejeski et al. (1987). We monitored hens using an ATS programmable-scanning receiver and a 4-element handheld Yagi antenna. Prior to 1 April, mortality was monitored daily by taking single readings. Beginning 1 April, triangulation occurred daily. Highly localized movements were assumed to be indicative of nest initiation (Porter 1978:61).

Effects of Burning and Discing Conservation Reserve Program Fields to Improve Habitat Quality for Northern Bobwhite (Colinus Virginianus)

Abstract Since 1985 considerable expanses of highly erodible cropland have been enrolled in the Conservation Reserve Program (CRP). Areas enrolled in CRP provide wildlife habitat; however, habitat quality and specific resources on these sites vary in relation to seasonal biological processes of target wildlife species, planted cover and vegetation succession. Throughout the southeastern United States habitat quality for early successional species, such as northern bobwhite (Colinus virginianus), may decline as CRP grasslands age. Although disturbance may enhance and maintain habitat quality for bobwhite, concerns regarding perceived conflicts between wildlife habitat and soil erosion objectives of the CRP persist. During 1995 and 1996 we evaluated effects of strip-discing or prescribed burning on vegetation structure and composition and soil erosion in fescue (Festuca arundiacea) dominated CRP fields in Mississippi. Fall discing generally increased percentage bare ground and plant diversity and decreased percentage litter cover and litter depth. Fall discing enhanced bobwhite habitat quality, but responses diminished by the second growing season post treatment. Burning increased plant diversity and improved quality of habitat for bobwhite. Soil loss for all treatments was within United States Department of Agriculture tolerable limits. Discing or burning intensity on CRP fields could be increased without compromising soil erosion provisions of CRP.

Survival of Reintroduced Ruffed Grouse in North Missouri

We studied survival of a reintroduced ruffed grouse (Bonasa umbellus) population in north Missouri from 16 September 1986 to 30 April 1987. Estimates of survival were derived from 77 radio-marked grouse with the Kaplan-Meier product-limit method. Survival from release to spring was 0.245 ? 0.05 (SE) and was not constant. Most losses occurred from release through fall. Adult male survival differed from that of immature males and immature females. No other differences were evident among age and sex classes. Grouse whose movements exceeded the mean daily movement had higher mortality rates than more sedentary birds. Survival of grouse into the breeding season may limit the success of reintroductions. J. WILDL. MANAGE. 52(2):248-252 Ruffed grouse were extirpated from major portions of their southern range during the late 1800s and early 1900s because of exploitative land use practices (Bump et al. 1947, Lewis 1970). Unregulated sport and market hunting also contributed to the decline (Hunyadi 1984). Since the 1950s many states have initiated ruffed grouse restoration programs with varied success (Lewis et al. 1968, White and Dimmick 1978, Backs 1984, Woolf et al. 1984). Estimates of grouse survival from release until the subsequent breeding season are useful to evaluate restoration programs. However, data are not available concerning the effect of condition or movements on the survival of reintroduced ruffed grouse. Objectives of our study were to determine survival of reintroduced ruffed grouse in north Missouri during September 1986-April 1987 and to examine the effect of condition and movement on grouse survival. We thank J. A. Balkenbush and V. L. Kimmel-Truitt for assisting in field work. The staff of the Missouri Department of Conservation, Kirksville, provided essential assistance. G. S. Olson and S. L. Sheriff assisted with data analyses and study design. This study was supported, in part, with the Federal Aid in Wildlife Restoration Act funds, under Pittman-Robertson Project W-13-R. R. M. Scheidt typed drafts of the manuscript. L. D. Vangilder, E. K. Fritzell, J. B. Lewis, D. T. Zekor, and F. R. Thompson reviewed the manuscript. STUDY AREA AND METHODS From 16 September to 7 October 1986, 77 ruffed grouse (42 ad, 35 immature) were released on Sugar Creek State Forest (SCSF) in Adair County, Missouri. Wild-trapped grouse were obtained from the Indiana Department of Natural Resources through a cooperative agreement with the Missouri Department of Conservation. The 1,056-ha SCSF, located in northcentral Missouri, is >90% forested. Most stands are composed of small sawlog and pole-sized oak (Quercus spp.) and hickory (Carya spp.). Since 1980, 7 stands totaling 72 ha were clearcut on SCSF and 128 ha received intermediate thinnings. Private lands surrounding the study area are a mosaic of forest, pasture, and cropland. Vegetative conditions of SCSF met the criteria for ruffed grouse release sites in Missouri (Hunyadi 1984, Kurzejeski et al. 1987a): a minimum size of 404 ha, predominantly forested, >10% in early forest succession, and an active timber management program. Grouse were released in a 6-year-old clearcut (9.8 ha) centrally located within the eastern unit of SCSF. Age (Davis 1969), sex (Roussel and Ouellet 1975), and weight of grouse were determined at release. Weight loss between time of capture and release was recorded and used as an indication of condition. Each bird was fitted with a mortality-sensitive, poncho-mounted transmitter (Advanced Telem. Systems, Inc., Isanti, Minn.). The 16-18-g transmitters had an expected life of 200 days and were assumed not to affect movements or survival of grouse (Small and Rusch 1985). We attempted to relocate grouse daily from date of release through 30 April 1987 with vehicle-mounted antennae and portable receivers. When necessary, fixed-wing aircraft were used to relocate grouse. Triangulation error with the vehicle-mounted antenna system was estimated at ?1.440 (n = 448) (Springer 1979). We estimated time of death within 24 hours of receiv-