JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.Abstract: One step in assessing the quality of an urban environment as habitat for a species is to compare its breeding ecology and productivity in urban and exurban (i.e., undeveloped, natural) areas. We studied Cooper's hawks (Accipiter cooperii) in Tucson, Arizona, and in exurban areas in southeastern Arizona, 1994-96. Urban pairs nested earlier (P < 0.001) and had larger clutches (P = 0.085) than exurban pairs. Nestling mortality was greater among urban nests (50.3%) than exurban nests (4.9%). The primary cause of death among urban nestlings was trichomoniasis (79.9%), which was a consistent mortality factor among years (P = 0.402). An overall failure rate among urban nests (52.6%) was greater than at exurban nests (20.5%; P < 0.001). Although the role of bird feeding in the spread of trichomoniasis remains unclear, promoting "dove-proof" feeders or abstinence from bird feeding may minimize the spread of the disease among prey species, thereby reducing mortality of nestling Cooper's hawks. The greatest cause of mortality among free-ranging Cooper's hawks in the urban area was collisions (69.8%), primarily with windows. Techniques to decrease window collisions should be promoted to reduce window-strike mortalities among both Cooper's hawks and their prey. Cooper's hawks also are occasionally aggressive when defending their nests from perceived threats, which may lead to fear and persecution by city residents. Hence, environmental education may be an important component of managing this species in urban settings. JOURNAL OF WILDLIFE MANAGEMENT 63(1):77-84

The decline in population and range of lesser prairie‐chickens (Tympanuchus pallidicinctus) throughout the central and southern Great Plains has raised concerns considering their candidate status under the United States Endangered Species Act. Baseline ecological data for lesser prairie‐chickens are limited, especially for the shinnery oak‐grassland communities of Texas. This information is imperative because lesser prairie‐chickens in shinnery oak grasslands occur at the extreme southwestern edge of their distribution. This geographic region is characterized by hot, arid climates, less fragmentation, and less anthropogenic development than within the remaining core distribution of the species. Thus, large expanses of open rangeland with less anthropogenic development and a climate that is classified as extreme for ground nesting birds may subsequently influence nest ecology, nest survival, and nest site selection differently compared to the rest of the distribution of the species. We investigated the nesting ecology of 50 radio‐tagged lesser prairie‐chicken hens from 2008 to 2011 in the shinnery oak‐grassland communities in west Texas and found a substantial amount of inter‐annual variation in incubation start date and percent of females incubating nests. Prairie‐chickens were less likely to nest near unimproved roads and utility poles and in areas with more bare ground and litter. In contrast, hens selected areas dominated by grasses and shrubs and close to stock tanks to nest. Candidate models including visual obstruction best explained daily nest survival; a 5% increase in visual obstruction improved nest survival probability by 10%. The model‐averaged probability of a nest surviving the incubation period was 0.43 (SE = 0.006; 95% CI: 0.23, 0.56). Our findings indicate that lesser prairie‐chicken reproduction during our study period was dynamic and was correlated with seasonal weather patterns that ultimately promoted greater grass growth earlier in the nesting season that provided visual obstruction from predators. © 2014 The Wildlife Society.

The Southern High Plains is anticipated to experience significant changes in temperature and precipitation due to climate change. These changes may influence the lesser prairie-chicken (Tympanuchus pallidicinctus) in positive or negative ways. We assessed the potential changes in clutch size, incubation start date, and nest survival for lesser prairie-chickens for the years 2050 and 2080 based on modeled predictions of climate change and reproductive data for lesser prairie-chickens from 2001–2011 on the Southern High Plains of Texas and New Mexico. We developed 9 a priori models to assess the relationship between reproductive parameters and biologically relevant weather conditions. We selected weather variable(s) with the most model support and then obtained future predicted values from climatewizard.org. We conducted 1,000 simulations using each reproductive parameter’s linear equation obtained from regression calculations, and the future predicted value for each weather variable to predict future reproductive parameter values for lesser prairie-chickens. There was a high degree of model uncertainty for each reproductive value. Winter temperature had the greatest effect size for all three parameters, suggesting a negative relationship between above-average winter temperature and reproductive output. The above-average winter temperatures are correlated to La Niña events, which negatively affect lesser prairie-chickens through resulting drought conditions. By 2050 and 2080, nest survival was predicted to be below levels considered viable for population persistence; however, our assessment did not consider annual survival of adults, chick survival, or the positive benefit of habitat management and conservation, which may ultimately offset the potentially negative effect of drought on nest survival.