Lesser prairie‐chicken (Tympanuchus pallidicinctus) populations have declined rangewide, and one of the principal causes is thought to be low nest success. Little is known about the relationship of vegetation structure and human intrusion to lesser prairie‐chicken nest location and success. We conducted our study from 1997 to 2002 in southwestern Kansas, USA, on 2 sand‐sagebrush (Artemisia filifolia) prairie areas managed for livestock production. We determined apparent nest success (26%) for 200 of 209 lesser prairie‐chicken nests located. Nest sites had taller grass, greater sand‐sagebrush density, and higher visual obstruction than random locations in the surrounding prairie. We recorded the distances from nests to 6 anthropogenic features (wellheads, buildings, improved roads, unimproved roads, transmission lines, center‐pivot irrigation fields) to determine whether the features were related to nest location and success. Sand‐sagebrush habitat around 5 of 6 features (all except unimproved roads) was avoided for 80 m (wellheads) to >1,000 m (buildings) by nesting lesser prairie‐chickens, but distances to the features were not substantial predictors of apparent nest success. Grass height, sagebrush plant density, and sagebrush height were the most important vegetation characteristics influencing nest success.

We flew aerial line-transect surveys to estimate the range-wide population size of lesser prairiechickens (Tympanuchus pallidicinctus) in the Great Plains, United States in 2012 and 2013. We also estimated the number of lesser prairie-chicken leks, the number of mixed-species leks that contained both lesser and greater prairie-chickens (T. cupido) and the number of hybrid lesser-greater prairie-chickens where these species' ranges overlap. The study area included the 2011 estimated occupied lesser prairie-chicken range in 5 states and was divided into 4 ecoregions. We created a sampling frame over the study area, consisting of 536 15-Â 15-km grid cells. We flew 512 transects within a probabilistic sample of 256 cells totaling 7,680 km in 2012 and 566 transects within a probabilistic sample of 283 cells totaling 8,490 km in 2013. We estimated a total of 34,440 individual lesser prairie-chickens in 2012 (17,615 in 2013) and 350 hybrid lesser-greater prairie-chickens in 2012 (342 in 2013) in the study area. We estimated a total of 2,930 lesser prairie-chicken leks in 2012 (2,037 in 2013) and 453 lesser and greater prairie-chicken mixed leks in 2012 (356 in 2013) in the study area. We discuss the implications of alternative sampling designs with regard to conservation questions to be addressed. Ó 2014 The Wildlife Society.

The lesser prairie‐chicken (Tympanuchus pallidicinctus) is currently considered a candidate for protection under the Endangered Species Act. To identify potential limiting factors for lesser prairie‐chicken populations, we developed an age‐based matrix model of lesser prairie‐chicken population dynamics to compare the relative importance of components of reproduction and survival, and determine if various management alternatives stabilize or increase rates of population change. We based our analyses on an intensive 6‐year population study from which demographic rates were estimated for each age class in Kansas. We used deterministic models and elasticity values to identify parameters predicted to have the greatest effect on the rate of population change (λ) at 2 study sites. Last, we used life‐stage simulation analysis to simulate various management alternatives. Lambda was <1 for both populations (site 1: λ = 0.54, site 2: λ = 0.74). However, we found differences in sensitivity to nest success and chick survival between populations. The results of the simulated management scenarios complemented the lower‐level elasticity analysis and indicated the relative importance of female survival during the breeding season compared with winter. If management practices are only capable of targeting a single demographic rate, changes to either nest success or chick survival had the greatest impact on λ at site 1 and 2, respectively. Management that simultaneously manipulated both nest success and chick survival was predicted to have a greater effect on λ than changes in survival of adult females. In practice, our demographic analyses indicate that effective management should be based on habitat conservation measures to increase components of fecundity.

Long‐term population declines and habitat reductions have increased concern over the status of the lesser prairie‐chicken (Tympanuchus pallidicinctus). Robust estimates of demographic parameters are essential for identifying population declines and planning effective management. We evaluated the effects of age and season on the survival of female lesser prairie‐chickens at 2 sites in southwestern Kansas, USA. Using telemetry data from a 7‐year field study (from 1997 to 2003), we estimated seasonal (Apr—Sep) and annual (Apr—Mar) survival. We also examined daily survival rates of females attending nests during the 26‐day incubation period and young during the 14‐day early brood‐rearing period. We evaluated the probable mortality causes of radiomarked birds by examining evidence at recovery sites. We captured 227 female lesser prairie‐chickens (87 yearlings, 117 ad, and 23 age undetermined) and fitted them with radiotransmitters. Estimates of 12‐month survival were lower among yearlings (Ŝ12 = 0.429, SE = 0.117) and adults at site I (Ŝ12 > = 0.302, SE = 0.080) than among yearlings (Ŝ12 = 0.588, SE = 0.100) and adults at site II (Ŝ12 > = 0.438, SE = 0.083). The patterns in timing of mortality and age‐specific 6‐month survival were consistent with those of 12‐month estimates at site I from 1998 to 2002, with a peak in mortality during May and June. Females tending to nests or to prefledged chicks had lower daily survival (DŜRtend = 0.993, SE = 0.001) than females not involved in these activities (DŜRfailedbreeder = 0.997, SE = 0.002). We recorded 92 mortalities from April 1997 to March 2003, and 59% and 11% were attributed to predation by mammals and raptors, respectively. Our research suggests that predation during the nesting season can have a major impact on lesser prairie‐chicken demography, and conservation efforts should focus on enhancing female survival during the nesting and brood‐rearing seasons.

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