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The Western Gulf Coast provides important habitat for migratory and resident waterfowl. The mottled duck(Anas fulvigula) relies on this region for all of its life-cycle events. Its relatively small population, limited worldwide range, and generally declining population trajectory has earned it a “Red” status on the Audubon WatchList and is a species of concern among state and federal agencies. The Western Gulf Coast (WGC) mottled duck population decline is believed to be primarily caused by the historical conversion and degradation of coastal wetlands and native prairie, and recent declines in cultivated rice. There is general agreement among experts that negative impacts to nesting and brood-rearing habitat are...
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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...
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The potential ecological and economic effects of climate change for tropical islands were studied using output from 12 statistically downscaled general circulation models (GCMs) taking Puerto Rico as a test case. Two model selection/model averaging strategies were used: the average of all available GCMs and the average of the models that are able to reproduce the observed large-scale dynamics that control precipitation over the Caribbean. Five island-wide and multidecadal averages of daily precipitation and temperature wereestimated by way of a climatology-informed interpolation of the site-specific downscaled climate model output. Annual cooling degree-days (CDD) were calculated as a proxy index for air-conditioning...
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Beaded streams are widespread in permafrost regionsand are considered a common thermokarst landform.However, little is known about their distribution, how andunder what conditions they form, and how their intriguingmorphology translates to ecosystem functions and habitat.Here we report on a circum-Arctic survey of beaded streamsand a watershed-scale analysis in northern Alaska using remotesensing and field studies.We mapped over 400 channelnetworks with beaded morphology throughout the continuouspermafrost zone of northern Alaska, Canada, and Russiaand found the highest abundance associated with mediumto high ground-ice content permafrost in moderately slopingterrain. In one Arctic coastal plain watershed, beaded...
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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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This project will provide a comprehensive synthesis of beaver recolonization science and techniques for successful reintroduction or population expansion through a thorough, in-depth, coordinated review of all North American beaver-related information, including identification of research gaps and data needs, and recommendations for project implementation. This information will be disseminated through a series of one-day workshops.
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ire-induced permafrost degradation is well documented in boreal forests, but the role of fires in initiating thermokarst development in Arctic tundra is less well understood. Here we show that Arctic tundra fires may induce widespread thaw subsidence of permafrost terrain in the first seven years following the disturbance. Quantitative analysis of airborne LiDAR data acquired two and seven years post-fire, detected permafrost thaw subsidence across 34% of the burned tundra area studied, compared to less than 1% in similar undisturbed, ice-rich tundra terrain units. The variability in thermokarst development appears to be influenced by the interaction of tundra fire burn severity and near-surface, ground-ice content....
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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...
Worldwide, many species are responding to ongoing climate change with shifts in distribution, abundance, phenology, or behavior. Consequently, natural-resource managers face increasingly urgent conservation questions related to biodiversity loss, expansion of invasive species, and deteriorating ecosystem services. We argue that our ability to address these questions is hampered by the lack of explicit consideration of species’ adaptive capacity (AC). AC is the ability of a species or population to cope with climatic changes and is characterized by three fundamental components: phenotypic plasticity, dispersal ability, and genetic diversity. However, few studies simultaneously address all elements; often, AC is confused...
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Lakes are prevalent in the Arctic and thus play a key role in regional hydrology. Since manyArctic lakes are shallow and ice grows thick (historically 2 m or greater), seasonal ice commonly freezes tothe lake bed (bedfast ice) by winter’s end. Bedfast ice fundamentally alters lake energy balance and meltoutprocesses compared to deeper lakes that exceed the maximum ice thickness (floating ice) and maintainperennial liquid water below floating ice. Our analysis of lakes in northern Alaska indicated that ice-out ofbedfast ice lakes occurred on average 17 days earlier (22 June) than ice-out on adjacent floating ice lakes (9July). Earlier ice-free conditions in bedfast ice lakes caused higher open-water evaporation,...
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Seamless DEM for the Crown of the Continent Ecosystem with a 50km buffer. This DEM was created using Shuttle Radar Topography Mission (SRTM) 1 Arc-Second Global data. The SRTM DEM had nodata values in several regions, particularly mountain tops. NoData holes were filled with ASTER Global DEM Version 2. Note: While the ASTER Global DEM does not have the NoData problems, the layers derived from the ASTER DEM (ex: slope, aspect) have sensor anomalies and artifacts, especially visible in the prairie regions. Data originally in WGS 1984 Vertical height in meters DEM created 2016-Feb-09
Understanding local and geographic factors influencing species distributions is a prerequisite for conservation planning. Our objective in this study was to model local and geographic variability in elevations occupied by native and nonnative trout in the northwestern Great Basin, USA. To this end, we analyzed a large existing data set of trout presence (5,156 observations) to evaluate two fundamental factors influencing occupied elevations: climate-related gradients in geography and local constraints imposed by topography. We applied quantile regression to model upstream and downstream distribution elevation limits for each trout species commonly found in the region (two native and two nonnative species). With...
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Article Introduction: Efforts to define water needs for riparian and aquatic ecosystems in arid and semi-arid systems are critical because riparian areas are essential for the survival of desert life, with stream corridors providing a large proportion of ecosystem services in these landscapes (Poff, Koestner, Neary, & Henderson, 2011; Millennium Ecosystem Assessment, 2005). To create a one-stop-shop for published ecological water needs information and illuminate critical knowledge gaps in the desert watersheds of the U.S. and Mexico, the University of Arizona’s Water Resources Research Center and the Northern Arizona University School of Earth Sciences and Environmental Sustainability created the Desert Flows Database....
Categories: Data, Publication; Types: Citation, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: Aquascalientes, Arizona, Baja California, California, Chihuahua, All tags...
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Dispersal can strongly influence the demographic and evolutionary trajectory of populations. For many species, little is known about dispersal, despite its importance to conservation. The Greater Sage-Grouse (Centrocercus urophasianus) is a species of conservation concern that ranges across 11 western U.S. states and 2 Canadian provinces. To investigate dispersal patterns among spring breeding congregations, we examined a 21-locus microsatellite DNA dataset of 3,244 Greater Sage-Grouse sampled from 763 leks throughout Idaho, Montana, North Dakota, and South Dakota, USA, across 7 yr. We recaptured ~2% of individuals, documenting 41 instances of breeding dispersal, with 7 dispersal events of .50 km, including 1 of...
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Governmental and nongovernmental organizations charged with managingnatural resources increasingly emphasize the need to work across jurisdictional boundaries.Their challenge is to manage shifting resources under rapidly changing climate andland-use scenarios. Scientists, resource managers, and conservation planners, and theirorganizations and agencies routinely collaborate on projects to solve specific problems.Cooperative frameworks to programmatically address complex social–environmental issuesand develop shared research, planning, and implementation priorities are relatively new.One such framework includes 22 Landscape Conservation Cooperatives that encompass the US, Caribbean countries, and bordering regions...
The exotic annual grass Bromus tectorum (cheatgrass) dominates vast acreages of rangeland in the western USA, leading to increased fire frequency and ecosystem degradation that is often irreversible. Episodic regeneration failure (“die-off”) has been observed in cheatgrass monocultures and can have negative ecosystem consequences, but can also provide an opportunity for restoration of native species and ecological function within the imperiled sagebrush steppe ecosystem. Proximate causes of cheatgrass die-off are uncertain, although several taxa of fungal soil pathogens have been implicated. Die-off occurrence is stochastic and can occur in remote areas. Thus, developing remote sensing indicators that are repeatable...
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In Arctic ecosystems, freshwater fish migrateseasonally between productive shallow water habitatsthat freeze in winter and deep overwinter refuge in riversand lakes. How these movements relate to seasonal hydrologyis not well understood.We used passive integratedtransponder tags and stream wide antennae to track1035 Arctic grayling in Crea Creek, a seasonally flowingbeaded stream on the Arctic Coastal Plain, Alaska. Migrationof juvenile and adult fish into Crea Creek peakedin June immediately after ice break-up in the stream. Fishthat entered the stream during periods of high flow andcold stream temperature traveled farther upstream thanthose entering during periods of lower flow and warmertemperature. We used generalized...
map background search result map search result map Broad-scale Relationships Between Shorebirds and Landscapes in the Southern Great Plains The Beaver Restoration Guidebook Version 1.0 Crown of the Continent DEM Genetic recapture identifies long-distance breeding dispersal in Greater Sage-Grouse (Centrocercus urophasianus) Understanding Environmental Flows in Desert Rivers of the U.S. and Mexico through the Desert Flows Database Publication: Holocene records of environmental change in High Plains playa wetlands, Kansas, US Distribution and biophysical processes of beaded streams in Arctic permafrost landscapes Depth, ice thickness, and ice-out timing cause divergent hydrologic responses among Arctic lakes 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 Recent Arctic tundra fire initiates widespread thermokarst development Seasonal cues of Arctic grayling movement in a small Arctic stream: the importance of surface water connectivity Spatiotemporal scaling of North American continental interior wetlands: implications for shorebird conservation Climate Change Implications for Tropical Islands: Interpolating and Interpreting Statistically Downscaled GCM Projections for Management and Planning The Caribbean Landscape Conservation Cooperative: A New Framework for Effective Conservation of Natural and Cultural Resources in the Caribbean Publication: Decision support tool: Mottled duck habitat management and conservation in the Western Gulf Coast Climate Change Implications for Tropical Islands: Interpolating and Interpreting Statistically Downscaled GCM Projections for Management and Planning The Caribbean Landscape Conservation Cooperative: A New Framework for Effective Conservation of Natural and Cultural Resources in the Caribbean Distribution and biophysical processes of beaded streams in Arctic permafrost landscapes Depth, ice thickness, and ice-out timing cause divergent hydrologic responses among Arctic lakes Seasonal cues of Arctic grayling movement in a small Arctic stream: the importance of surface water connectivity 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 Genetic recapture identifies long-distance breeding dispersal in Greater Sage-Grouse (Centrocercus urophasianus) Publication: Holocene records of environmental change in High Plains playa wetlands, Kansas, US Broad-scale Relationships Between Shorebirds and Landscapes in the Southern Great Plains Crown of the Continent DEM Publication: Decision support tool: Mottled duck habitat management and conservation in the Western Gulf Coast Spatiotemporal scaling of North American continental interior wetlands: implications for shorebird conservation Recent Arctic tundra fire initiates widespread thermokarst development Understanding Environmental Flows in Desert Rivers of the U.S. and Mexico through the Desert Flows Database The Beaver Restoration Guidebook Version 1.0