Filters: Tags: Nest survival (X)12 results (61ms)
Raven Observations near Greater Sage-Grouse Nests in the Great Basin and Bi-State Regions of the Western United States (2009 - 2019)
These tables serve as input data for hierarchical models investigating interactions between raven density and Greater Sage-grouse nest success. Observations were recorded over an 11 year time period, spanning from 2009 through 2019. The model is run in JAGS via R, the code is publicly available via the U.S. Geological Survey's GitLab (O'Neil et al. 2023). We recommend not making any changes or edits to the tables unless the user is experienced with hierarchical modeling. References: O'Neil, S.T., Coates, P.S., Webster, S.C., Brussee, B.E., Dettenmaier, S.J., Tull, J.C., Jackson, P.J., Casazza, M.L., and Espinosa, S.P., 2023, Code for a hierarchical model of raven densities linked with sage-grouse nest survival...
Evaluating patterns of long-term system change and demographic response for grassland nesting ducks in the US Prairie Pothole Region
The US Prairie Pothole Region (PPR) has experienced some of the highest rates of grassland loss in North America over a time that coincides with dramatic declines in grassland songbird populations yet increasing abundance of most grassland-nesting duck species except for northern pintail. To provide more insight into this contradiction, we propose to capitalize on long-term databases to evaluate how a key population driver nest survival for North American ducks has responded to system changes in the region including landscape and climatic factors. Outcomes of these analyses will contribute to testing primary conservation planning assumptions for the PPJV a vital component of the PPJV Strategic Habitat Conservation...
Map of cumulative 38-day nest survival predicted from a Bayesian hierarchical shared frailty model of sage-grouse nest fates. The midpoint of coefficient conditional posterior distributions of 38-day nest survival were used for prediction at each 30 meter pixel across the landscape.
Ranked index of model-projected nest site selection integrated with nesting productivity (i.e., nest survival), demonstrating the spatial distribution of adaptive vs. maladaptive habitat selection at each 30 m pixel. Hierarchical models of nest selection and survival were fit to landscape covariates within a Bayesian modeling framework in Nevada and California from 2009 through 2017 to develop spatially explicit information about nest site selection and survival consequences across the landscape. Habitat was separated into 16 classes ranking from high (1) to low (16). Habitat ranked highest where the top nest selection and survival classes intersected (adaptive selection), whereas the lowest rank occurred where...
Rasters representing median raven density estimates, calculated from approximately 28,000 raven point count surveys conducted between 2009 and 2019. Estimates were the result of a Bayesian hierarchical distance sampling model, using environmental covariates on detection and abundance.
Map of nesting habitat selection scores predicted from a resource selection function (RSF) developed from sage-grouse nest locations. Nest site selection was modeled using a generalized linear mixed model of used and random locations in a Bayesian modeling environment, and the midpoint of coefficient conditional posterior distributions were used for prediction. Continuous values were reclassified and ranked using a percent isopleth approach with respect to observed nest locations.
Data to Support Hierarchical Models and Decision Support Maps to Guide Management of Subsidized Avian Predator Densities
We combined approximately 28,000 raven point count surveys with data from more than 900 sage-grouse nests between 2009 and 2019 within the Great Basin, USA. We modeled variation in raven density using a Bayesian hierarchical distance sampling approach with environmental covariates on detection and abundance. Concurrently, we modeled sage-grouse nest survival using a hierarchical frailty model as a function of raven density as well as other environmental covariates that influence risk of failure. Raven density commonly exceeded more than 0.5 ravens per square kilometer and increased at low relative elevations with prevalent anthropogenic development and/or agriculture. Reduced sage-grouse nest survival was strongly...
Nest success and predation data for Mariana swiftlets (Aerodramus bartschi), Hawai'i, USA, 2006-2010
This study examined the reproductive biology of the Mariana Swiftlet over five annual cycles on the island of O‘ahu in the Hawaiian Islands. This introduced population used a human-made tunnel for roosting and nesting, and was studied as a surrogate to negate interference with the endangered populations in the Mariana Islands. Active nests (N = 478) were observed in every month of the year. Data recorded included: nest visit dates, date nests were identified, number of visits to each nest; nest stage, nest fate, nest failure status, number of rat traps present, number of rats captures, daily rainfall, and nest ages.
Spatially-explicit Predictive Maps of Greater Sage-grouse Nest Selection Integrated with Nest Survival in Nevada and Northeastern California, USA
We applied spatially-explicit models to a spatiotemporally robust dataset of greater sage-grouse (Centrocercus urophasianus) nest locations and fates across wildfire-altered sagebrush ecosystems of the Great Basin ecoregion, western USA. Using sage-grouse as a focal species, we quantified scale-dependent factors driving nest site selection and nest survival across broad spatial scales in order to identify wildfire impacts and other environmental influences on variation in nesting productivity across a broad ecoregion spanning mesic and xeric shrub communities. To investigate the consequences of habitat selection and explore the potential for a source-sink reproductive landscape, we sought to classify nesting habitat...
Estimates of Raven Impacts on Greater Sage-Grouse Nest Survival Delineated by Field Site in California, Nevada, and Idaho (2009 - 2019)
These rasters are the result of calculating the difference in Greater Sage-grouse nest survival after a simulated reduction of raven density to 0.1 ravens per square kilometer. The difference in nest survival represents spatial variation in potential to improve nest survival by reducing raven impacts. The extent of each individual raster is the extent of the field site at which sage-grouse nest observations were recorded.
Native grasslands have been altered to a greater extent than any other biome in North America. The habitats and resources needed to support breeding performance of grassland birds endemic to prairie ecosystems are currently threatened by land management practices and impending climate change. Climate models for the Great Plains prairie region predict a future of hotter and drier summers with strong multiyear droughts and more frequent and severe precipitation events. We examined how fluctuations in weather conditions in eastern Colorado influenced nest survival of an avian species that has experienced recent population declines, the Mountain Plover (Charadrius montanus). Nest survival averaged 27.2% over a 7-yr...
The datasets stored in this folder summarize reproductive data for Brown Pelicans nesting on Gaillard and Cat Islands, Alabama, in 2017 and 2018. Data include nest and nestling survival, nest site characteristics, environmental covariates, and temperatures recorded inside nests.