Publications

In water-limited dryland ecosystems of the Western United States, climate change is intensifying the impacts of heat, drought, and wildfire. Disturbances often lead to increased abundance of invasive species, in part, because dryland restoration and rehabilitation are inhibited by limited moisture and infrequent plant recruitment events. Information on ecological resilience to...

The tire-rubber-derived ozonation product of N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD), N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine-quinone (6PPD-Q), was recently discovered to cause acute mortality in coho salmon (Oncorhynchus kisutch). para-Phenylenediamines (PPDs) with variable side chains distinct from 6PPD have been identified as potential replacement...

Carbon fluxes in tidal brackish marshes play a critical role in determining coastal wetland carbon sequestration and storage, thus affecting carbon crediting of coastal wetland restoration. In this study, a process-driven wetland biogeochemistry model, Wetland Carbon Assessment Tool DeNitrification-DeComposition was applied to nine brackish marsh sites in Mississippi River (MR) Deltaic...

Traps are used to catch adult sea lampreys during their upstream migration to estimate their abundance in streams and, in turn, provide a measure of the Sea Lamprey Control Program’s effectiveness. During 2015 and 2016, we experimentally compared two components of sea lamprey trap design: trap entrance funnel type and the presence of retention devices, using side-by-side instream test...

Remotely sensed imagery from various collection platforms (e.g., satellites, crewed and uncrewed aircraft) are used by biologists and other conservation personnel to support management activities ranging from monitoring invasive species to assessing land cover and vegetation characteristics. Although remote sensing–based vegetation indices and models have been developed and used for some

Sierra Nevada ecosystems have been influenced by fire for millennia; however, increasing wildfire size and frequency may yield unforeseen consequences on wildlife populations and their distribution. Foothill yellow-legged frogs Rana boylii have declined in portions of their range and are considered a species of conservation concern. We surveyed streams for foothill yellow legged frogs in...

The Snake River in Idaho, USA, supports a popular sport fishery for nonnative Smallmouth Bass Micropterus dolomieu, but there are limited studies on the population dynamics of this introduced species in Idaho and other water systems in the western United States. The purpose of this study was to describe the population dynamics and demographics of Smallmouth Bass in the Snake River, Idaho...

Rationale Vein calcite in Devils Hole has been precipitating continuously in oxygen-isotope equilibrium at a constant temperature for over 500 000 years, providing an unmatched δ18O paleoclimate time series. A substantial issue is that coeval calcite (based on matching δ18O values) has uranium-series ages differing by 12 000 years. Methods An unparalleled high-accuracy δ18O chronology...

The Little Sequatchie River and Pryor Cove Branch, in southern Tennessee, drain the eastern escarpment of the Cumberland Plateau to the Sequatchie River near the southern end of the Sequatchie Valley. The Little Sequatchie River is the largest tributary to the Sequatchie River by drainage area, covering over 120 square miles. The hydrology of the two drainage areas has been largely...

The U.S. Geological Survey constructed a two-dimensional hydrodynamic model that was applied to a 15.8-mile tailwater reach of the Colorado River in Glen Canyon that begins 0.25 mile downstream from Glen Canyon Dam and extends to Lees Ferry in Glen Canyon National Recreation Area, Arizona. The model used the Flow and Sediment Transport with Morphological Evolution of Channels (FaSTMECH)...

Geospatial data describing the topography, natural features, human-built features, and land uses of a particular area or region can come from independent data providers and, therefore, vary in format, data encoding, and geographic coverage. Because of the complexity of the processes and procedures required for unifying these heterogeneous data into a dataset with consistent format...

Site 11 is a former landfill at North Chevalier Field Disposal Area in Operable Unit 2 at Naval Air Station Pensacola, in northwest Florida. Site 11 is adjacent to Bayou Grande, a shallow, tidally influenced, saline estuary of the Pensacola Bay watershed. Federal and Florida regulators have expressed concern that contaminants detected in groundwater beneath the inland parts of Site 11...