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We used the lesser prairie‐chicken (Tympanuchus pallidicinctus), an iconic grouse species that exhibits a boom–bust life history strategy, on the Southern High Plains, USA, as a bioindicator of main and interactive effects of severe drought and grazing. This region experienced the worst drought on record in 2011. We surveyed lesser prairie‐chicken leks (i.e., communal breeding grounds) across 12 years that represented 7 years before the 2011 drought (predrought) and 4 years during and following the 2011 drought (postdrought). Grazing was annually managed with the objective of achieving ≤50% utilization of aboveground vegetation biomass. We used lek (n = 49) count data and covariates of weather and managed grazing to: (a) estimate long‐term lesser prairie‐chicken abundance and compare abundance predrought and postdrought; (b) examine the influence of annual and seasonal drought (modified Palmer drought index), temperature, and precipitation on long‐term lesser prairie‐chicken survival and recruitment; and (c) assess and compare the influence of grazing on lesser prairie‐chicken population predrought and postdrought. Lesser prairie‐chicken abundance was nearly seven times greater predrought than postdrought, and population declines were attributed to decreased survival and recruitment. The number of days with temperature >90th percentile had the greatest effect, particularly on recruitment. The population exhibited a substantial bust during 2011 and 2012 without a boom to recover in four postdrought years. Adaptive grazing positively influenced the population predrought, but had no effects postdrought. Results suggest that the severe drought in 2011 may have been beyond the range of environmental conditions to which lesser prairie‐chickens, and likely other species, have adapted. Land management practices, such as grazing, should remain adaptive to ensure potential negative influences to all species are avoided. Increasing habitat quantity and quality by reducing habitat loss and fragmentation likely will increase resiliency of the ecosystem and individual species. We used the lesser prairie‐chicken (Tympanuchus pallidicinctus), an iconic grouse species that exhibits a boom–bust life history strategy, on the Southern High Plains, USA, as a bioindicator of main and interactive effects of severe drought and grazing. The population exhibited a substantial bust during 2011–2012, primarily through reduced recruitment due to excessive heat, without a boom to recover in four postdrought years. Adaptive grazing positively influenced the population predrought, but had no effects postdrought. [ABSTRACT FROM AUTHOR]

Groundwater reliant and agriculturally dominant environments (GRADEs) utilize exhaustible aquifer resources to supply food and fiber demands. The sustainability of these GRADES is threatened by over‐exploitation of fresher groundwater resources. There is an interest in exploring deeper brackish groundwater resources to sustain agricultural based economies in these regions. Using the southern high plains of Texas (SHP) as a test‐bed, the interlinkages between food‐energy‐water on improving water resiliency through brackish groundwater development is explored. Three scenarios—(1) direct use of deeper formations; (2) blending deeper and shallower groundwaters and 3) desalination of blended resources were evaluated in a spatially explicit manner. The results indicate that direct reuse of deeper water is possible over 30% of the study area, but it is not available in areas of critical need. The parameters limiting the suitability of deeper groundwater for agriculture in the order of decreasing importance are EC > TDS > SAR > B > Na > Cl. Simple blending of water from deeper and shallower aquifers improve water quality over roughly 900,000 acres. While blending greatly reduces the specific ion toxicities caused by sodium absorption ratio (SAR) and boron (B), the limitations of total dissolved solids (TDS) cannot be overcome. The over‐burden pressures in the deeper confined aquifer somewhat alleviate the blending energy requirements, especially in the southern portions of SHP. Desalination increases the energy requirements by several fold and is not suitable to sustain current agricultural practices which are focused mostly on lower valued staple crops. Using desalinated water for municipal and industrial uses can help ameliorate the stresses on the Ogallala Aquifer and enhance its longevity. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 21–36, 2018 Novelty or Significance: The study is focused on the linkages between food, energy and water in groundwater dependent agricultural economies. Using the Southern High Plains of Texas as a test‐bed, the work evaluates whether a deeper brackish groundwater resource (Dockum geological unit) can be used to augment water supplies to sustain intensive agricultural production. The study identifies various factors that limit the use of this deeper resource and quantifies the energy footprint associated with three progressively complex approaches to improve water resiliency in the region and prolong the life of the Ogallala Aquifer. [ABSTRACT FROM AUTHOR]

Scaled quail (Callipepla squamata) populations have been declining since the early 1960s, and there is no clear understanding of what is causing this decline. It has been suggested that reproductive failure is a probable cause of this decline. We used radiotelemetry to evaluate nesting ecology and survival of scaled quail in the Southern High Plains of Texas in 1999 and 2000. We radio- marked 138 hens (66 in 1999 and 72 in 2000) and reported nesting activity on 106 nests. In 1999, 50 nests were detected with a nesting success of 44%. In 2000, 56 nests were detected with a nesting success of 64%. Chick survival was recorded at 21 days posthatch and was analyzed as present or absent, as exact numbers were difficult to determine. Two hens had chicks present at 21 days in 1999, but 16 hens had chicks present at 21 days in 2000. Chick presence with the hen at 21 days was negatively associated with cool and wet weather. Logistic regression revealed predictive relationships for models describing vegetation characteristics at and around nest sites as predictors of nesting success and nest sites. Variables in the models included percentage of bare ground, forb diversity, and amount of visual obstruction at different heights. Hen survival, nesting success, and chick survival were higher in 2000 than in 1999. Differences in vegetation composition and structure were likely responses to differences in precipitation between years. Drought and overgrazing by livestock increase the percentage of bare ground and reduce visual obstruction; these are likely contributors to the reduced scaled quail populations in the Southern High Plains. [ABSTRACT FROM AUTHOR]

Northern bobwhites (Colinus virginianus) are captured routinely for scientific study. Extreme exertion during restraint and transport can lead to acidosis and free radical production that result in muscle tissue damage. This condition, termed capture myopathy, can result in dyspnea, hyperthermia, weakness, muscle rigidity, and collapse. These complications could lead to increased susceptibility of individuals to predation or contribute to death weeks or months after capture. Death caused by capture could negatively bias mortality rate estimates if mortalities occur after traditional censor periods. We hypothesize that muscular damage incurred during capture handicaps northern bobwhites. We evaluated our hypothesis by comparing survival of northern bobwhite that were treated for muscular damage with an injection of vitamin E and selenium, a solution recommended in veterinary avian medicine, with bobwhites that were not treated. We captured northern bobwhite during 2002 and 2003 and injected half of the birds with 0.1 ml of a vitamin E and selenium solution and the other half with a saline control. We then transported these birds to our study site and monitored them using radiotelemetry. We estimated survival rates using the staggered-entry Kaplan-Meier Product Limit Estimator. The survival of treated birds was greater than the survival of control birds in 2002 at days 45 (58% vs. 29%, Z = 1.98, P = 0.05) and 66 (53% vs. 29%, Z = 1.79, P = 0.07), a period before and after which sample sizes were very small. Treated birds exhibited a greater (χ² = 7.11, P < 0.008) survival curve than control birds during 2003 and when treatments were pooled by year (χ² = 4.19, P = 0.04). Thus, our data suggest that injection of wild northern bobwhite with vitamin E and selenium increased survival of transplanted birds as compared to control birds injected with saline. [ABSTRACT FROM AUTHOR]

Agricultural land use may indirectly affect the body size of amphibians by altering the hydroperiods of nearby wetlands and influencing amphibian densities—both factors which can limit the larval and postmetamorphic growth rates of amphibians. We measured postrrietamorphic body size for 4 species (Spea multiplicata, S. boinbifrons, Bufo cognatus, Ambystoma tigrinum mavortium) and 3 age classes (metamorph, subadult, adult) of amphibians captured at playa wetlands surrounded by one of 2 general land-use types (cultivation, grassland) in the Southern High Plains. Sixteen playas (4 per land-use type in 1999 and 2000) were partially enclosed with drift fence and pitfall traps, and mass and snout-vent length (SVL) were measured from a subsample of captured individuals. Mass and SVL were 10-148% greater for amphibians captured at grassland wetlands than at cropland wetlands for most species and age classes. Mass and SVL also were 3-124% greater in 1999 than in 2000 for most species and age classes. We attribute differences in body size between land-use types to differences in the hydroperiods of the associated wetlands, and potentially to variation in the density of terrestrial conspecifics and aquatic predators. We attribute differences in body size between years to differences in rainfall. Body size is positively related to the probability of survival, reproduction, and evolutionary fitness in amphibians. Thus, if cultivation of landscapes surrounding wetlands negatively influences postmetamorphic body size of amphibians, restoration of native grasslands surrounding playa wetlands may help prevent local amphibian declines. [ABSTRACT FROM AUTHOR]

Breeding-bird communities inhabiting northern prairie wetlands have been shown to have higher densities and diversities in wetlands with a well-interspersed 50:50 vegetative cover:water ratio than in those wetlands with a higher or lower proportion of cover. Potential reasons for such a response include increased food or visual isolation and spacing of breeding birds. We manipulated cover:water ratios (75:25, 50:50, 25:75) in Southern Great Plains playas and examined avian response (i.e., species richness, nonwaterfowl bird density, and waterfowl density) to these patterns in winter. We found the highest species richness and generally the highest waterfowl densities in the 50:50 cover:water treatment. Because the amount of vegetative food was similar among treatments and waterfowl inhabiting playas during winter are forming pair bonds, it is most likely that the optimal edge and visual isolation provided in the 50:50 cover:water treatment contributed to its high use and richness. Nonwaterfowl bird density was not different among the treatments. Many nonwaterfowl birds using playas in winter, such as McCown's longspur (Calcarius mccownii), occur as nonbreeding feeding flocks, are not forming pair bonds, and likely are not responding to particular cover:water treatments. Playa wetland biologists should create a well-interspersed 50:50 cover:water ratio to optimize waterfowl use and avian species richness. [ABSTRACT FROM AUTHOR]