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Global environmental change has influenced lake surface temperatures, a key driver of ecosystem structureand function. Recent studies have suggested significant warming of water temperatures in individual lakesacross many different regions around the world. However, the spatial and temporal coherence associatedwith the magnitude of these trends remains unclear. Thus, a global data set of water temperature isrequired to understand and synthesize global, long-term trends in surface water temperatures of inlandbodies of water. We assembled a database of summer lake surface temperatures for 291 lakes collectedin situ and/or by satellites for the period 1985–2009. In addition, corresponding climatic drivers (airtemperatures,...
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How local geomorphic and hydrologic features mediate the sensitivity of stream thermal regimesto variation in climatic conditions remains a critical uncertainty in understanding aquatic ecosystem responsesto climate change.We used stable isotopes of hydrogen and oxygen to estimate contributions of snow and rainfallto 80 boreal streams and show that differences in snow contribution are controlled by watershed topography.Time series analysis of streamthermal regimes revealed that streams in rain-dominated, low-elevation watershedswere 5–8 times more sensitive to variation in summer air temperature compared to streams draining steepertopography whose flows were dominated by snowmelt. This effect wasmore pronounced...
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Within interior North America, erratic weather patterns and heterogeneous wetland complexes cause wide spatio-temporal variation in the resources available to migrating shorebirds. Identifying the pattern-generating components of landscape-level resources and the scales at which shorebirds respond to these patterns will better facilitate conservation efforts for these species. We constructed descriptive models that identified weather variables associated with creating the spatio-temporal patterns of shorebird habitat in ten landscapes in north-central Oklahoma. We developed a metric capable of measuring the dynamic composition and configuration of shorebird habitat in the region and used field data to empirically...
The restoration of historical fire regimes is often a primary objective in the conservation of fire-adapted forests. However, individual species’ responses to future climate change may uncouple historical vegetation–disturbance relationships, producing potentially negative ecological consequences to fire restoration. We used a landscape simulation model to assess how forest pattern will respond to future climate regimes and whether the restoration of historical fire regimes will benefit forest conservation under future climate regimes. Our study landscape was the 335,000-ha Kaibab Plateau at the North Rim of the Grand Canyon spanning a broad elevation-vegetation gradient of pinyon-juniper, ponderosa pine, mixed...
Open canopy conditions in southeastern pine (Pinus spp.) forests were historically maintained by frequent fire and other disturbances, without which midstory hardwoods create closed canopy conditions limiting value of pine stands for many endemic, disturbance-adapted species. Intensively managed pine forests, which comprise 19% of forests in the southeastern U.S., can emulate historical open pine conditions, providing appropriate vegetation structure and composition for many endemic species. However, exact mechanisms for producing and maintaining open pine conditions and subsequent effects on biodiversity have not been examined across regions and stand ages. To better inform managers about options for providing...
The development of robust modelling techniques to derive inferences from large- scale migratory bird monitoring data at appropriate scales has direct relevance to their management. The Integrated Waterbird Management and Monitoring programme (IWMM) represents one of the few attempts to monitor migrating waterbirds across entire flyways using targeted local surveys. This dataset included 13,208,785 waterfowl (eight Anas species) counted during 28,000 surveys at nearly 1,000 locations across the eastern United States between autumn 2010 and spring 2013 and was used to evaluate potential predictors of waterfowl abundance at the wetland scale. Mixed-effects, log- linear models of local abundance were built for the Atlantic...
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Stopover use by migrating shorebirds is affected by patch-level characteristics of habitat, but the relative influence of broadscale factors is poorly understood. We conducted surveys of ten 10-km-radius landscapes in north-central Oklahoma from 2007 through 2009 to examine the influence of the amount and composition of wetland habitats and surrounding land cover on shorebird use during migration. We used generalized linear modeling and an information-theoretic framework to identify factors that best explained species richness, total abundance, and abundance of four groups of shorebirds classified by breeding status and migration distance. Total abundance and richness both increased with the area of wetland...
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Holocene environmental change is poorly characterized throughout much of the High Plains. Playa wetlands are sites with appreciable potential for reconstructing environmental change because of their environmental sensitivity. Radiocarbon, litho- and magneto-stratigraphic, and stable carbon isotope (δ13C) data for four playas on the Kansas High Plains indicate significant change occurred throughout the Holocene, which had profound impacts on playa ecosystem functions (e.g. groundwater recharge, surface water storage, and habitat). Minimum δ13C values and buried soils observed during the Pleistocene–Holocene transition suggest sufficient moisture to support vegetative cover and promote pedogenesis. Low magnetic susceptibility,...
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There is mounting concern that climate change will lead to the collapse of cyclic population dynamics, yet the influence of climate variability on population cycling remains poorly understood. We hypothesized that variability in survival and fecundity, driven by climate variability at different points in the life cycle, scales up from local populations to drive regional characteristics of population cycling and spatial synchronization.
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The availability of output from climate model ensembles,such as phases 3 and 5 of the Coupled Model Intercomparison Project(CMIP3 and CMIP5), has greatly expanded information about future projections,but there is no accepted blueprint for how this data should be utilized.The multi-model average is themost commonly cited single estimate of future conditions,but higher-order moments representing thevariance and skewness of the distribution of projections provide important information about uncertainty. We have analyzed a set of statistically downscaled climate model projections from the CMIP3 archive to assess extreme weather events at a level aimed to be appropriate for decisionmakers. Our analysis uses the distribution...
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Landscape Conservation Cooperatives (LCCs) are public-private partnerships composed of states, tribes, federal agencies, non-governmental organizations, universities, international jurisdictions, and others working together to address landscape and seascape scale conservation issues. LCCs inform resource management decisions to address broad-scale stressors-including habitat fragmentation, genetic isolation, spread of invasive species, and water scarcity-all of which are magnified by a rapidly changing climate. For further information go to https://www.fws.gov/science/catalog. The previous 2011 LCC Network Areas data is available at https://www.sciencebase.gov/catalog/item/52f2735ee4b0a6f0bd498c2f
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Landscape Conservation Cooperatives (LCCs) are public-private partnerships composed of states, tribes, federal agencies, non-governmental organizations, universities, international jurisdictions, and others working together to address landscape and seascape scale conservation issues. LCCs inform resource management decisions to address broad-scale stressors-including habitat fragmentation, genetic isolation, spread of invasive species, and water scarcity-all of which are magnified by a rapidly changing climate. For further information go to https://www.fws.gov/science/catalog. The previous 2011 LCC Network Areas data is available at https://www.sciencebase.gov/catalog/item/52f2735ee4b0a6f0bd498c2f
One of the most influential environmental laws in the US – the 1972 Clean Water Act – included the visionary objective of maintaining and restoring aquatic ecological integrity. However, the efficacy of the Act depends on how integrity is assessed. Reviewing the assessment literature for fresh waters over the past 40 years, we found evidence of methodological trends toward increased repeatability, transferability, and robustness of assessments over time. However, implementation gaps were revealed, based on the relatively weak linkages to freshwater policies, stakeholder involvement, emerging threats, and conservation opportunities. A related survey of assessment practitioners underscored the disparity between need...
The purpose of the North American Bat Monitoring Program (NABat) is to create a continent-wide program to monitor bats at local to rangewide scales that will provide reliable data to promote effective conservation decisionmaking and the long-term viability of bat populations across the continent. This is an international, multiagency program. Four approaches will be used to gather monitoring data to assess changes in bat distributions and abundances: winter hibernaculum counts, maternity colony counts, mobile acoustic surveys along road transects, and acoustic surveys at stationary points. These monitoring approaches are described along with methods for identifying species recorded by acoustic detectors. Other chapters...
Categories: Data, Publication; Types: Citation; Tags: BIOLOGICAL RECORDS, BIOLOGICAL RECORDS, BIOLOGICAL RECORDS, BIOLOGICAL RECORDS, BIOSPHERE, All tags...
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Executive Summary: We provide an analysis of Sonoran Desert water network connectivity to inform managers of current conditions for target wildlife and how the connectivity will change as the landscape becomes more water limited.Climate change is expected to lead to fragmentation of the network, increasing coalescence distance by 8% and reducing the persistence and overall number of waters on the landscape. Identification of key water sites, ranked by network connectivity metrics, are presented in Appendix B. Wetland number under our scenario of water limitation will decline by 43% reducing network resilience.Anurans and Caudates, although varying in ability to disperse, generally experienced reduced connectivity...
“The loss of foundational but fire-intolerant perennials such as sagebrush due to increases in fire size and frequency in semi-arid regions has motivated efforts to restore them, often with mixed or even no success. Seeds of sagebrush Artemisia tridentata and related species must be moved considerable distances from seed source to planting sites, but such transfers have not been guided by an understanding of local climate adaptation. Initial seedling establishment and its response to weather are a key demographic bottleneck that likely varies among subspecies and populations of sagebrush.We assessed differences in survival, growth and physiological responses of sagebrush seedlings to weather among eleven seed sources...
Bromus species – such as cheatgrass – are exotic annual grasses that have become the dominant annual grasses in the western hemisphere. Their spread and impacts across the western United States continue despite the many attempts by land managers to control these species. A new book edited by scientists from the U.S. Geological Survey, U.S. Forest Service and Colorado State University answers critical research, planning, and management questions about these species. The book synthesizes available literature on the biology, ecology, sociology and economics of Bromus grasses to develop a more complete picture of the factors that influence their invasiveness, impacts, and management in the western United States. Lessons...
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Throughout the Arctic most pregnant polar bears (Ursus maritimus) construct maternity dens in seasonal snowdrifts that form in wind-shadowed areas. We developed and verified a spatial snowdrift polar bearden habitat model (SnowDens-3D) that predicts snowdrift locations and depths along Alaska’s Beaufort Sea coast. SnowDens-3D integrated snow physics, weather data, and a high-resolution digital elevation model (DEM) to produce predictions of the timing, distribution, and growth of snowdrifts suitable for polar bear dens. SnowDens-3D assimilated 18 winters (1995 through 2012) of observed daily meteorological data and a 2.5 m grid-increment DEM covering 337.5 km2 of the Beaufort Sea coast, and described the snowdrift...
AbstractContext Conservation planning is increasingly using ‘‘coarse filters’’ based on the idea of conserving ‘‘nature’s stage’’. One such approach is based on ecosystems and the concept of ecological integrity, although myriad ways exist to measure ecological integrity.Objectives To describe our ecosystem-based index of ecological integrity (IEI) and its derivative index of ecological impact (ecoImpact), and illustrate their applications for conservation assessment and planning in the northeastern United States.Methods We characterized the biophysical setting of the landscape at the 30 m cell resolution using a parsimonious suite of settings variables. Based on these settings variables and mapped ecosystems, we...
AbstractUrban development is a principal driver of landscape change affecting the integrity of ecological systems and the capacity of the landscape to support species. We developed an urban growth model (SPRAWL), evaluated it with hindcasting, and used it to simulate urban growth across the northeastern United States between 2010 and 2080 under four alternative scenarios. In the model, urban growth is constrained by demand for new development for each time step at the subregional scale. Demand is subsequently allocated to local application panes (5 km on a side within 15 km window) using a unique landscape context matching algorithm, such that the more historical development that occurred in the matched training...
map background search result map search result map Broad-scale Relationships Between Shorebirds and Landscapes in the Southern Great Plains Quantitative and Predictive Analysis: Landscape Connectivity of Isolated Waters for Wildlife in the Sonoran Desert Publication: Interpreting climate model projections of extreme weather events Publication: Climate variability drives population cycling and synchrony Publication: Holocene records of environmental change in High Plains playa wetlands, Kansas, US Modeling snowdrift habitat for polar bear dens Watershed geomorphology and snowmelt control stream thermal sensitivity to air temperature. A global database of lake surface temperatures collected by in situ and satellite methods from 1985–2009 Spatiotemporal scaling of North American continental interior wetlands: implications for shorebird conservation Modeling snowdrift habitat for polar bear dens Watershed geomorphology and snowmelt control stream thermal sensitivity to air temperature. A global database of lake surface temperatures collected by in situ and satellite methods from 1985–2009 Publication: Holocene records of environmental change in High Plains playa wetlands, Kansas, US Quantitative and Predictive Analysis: Landscape Connectivity of Isolated Waters for Wildlife in the Sonoran Desert Broad-scale Relationships Between Shorebirds and Landscapes in the Southern Great Plains Spatiotemporal scaling of North American continental interior wetlands: implications for shorebird conservation Publication: Interpreting climate model projections of extreme weather events Publication: Climate variability drives population cycling and synchrony