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The Lees Ferry reach of the Colorado River-a 16-mile segment from Glen Canyon Dam to the confluence with the Paria River-supports an important recreational rainbow trout (Oncorhynchus mykiss) fishery. In Grand Canyon, nonnative rainbow trout prey on and compete for habitat and food with native fish, such as the endangered...

Since 1979, abundances of sauger Stizostedion canadense have declined in the Tennessee River system. Reasons for this decline may include overharvest, loss of spawning habitat, and low recruitment due to extreme flows. The purpose of this study was to investigate the movements of saugers following winter concentration below Pickwick Dam, Tennessee. Thirty-seven...

Growing evidence supports the notion that plutons are constructed incrementally, commonly over long periods of time, yet field evidence for the multiple injections that seem to be required is commonly sparse or absent. Timescales of up to several million years, among other arguments, indicate that the dominant volume does...

In this report we describe how we adapted two techniques for sampling lake sturgeon (Acipenser fulvescens) and other fish early life history stages to meet our research needs in the Detroit River, a deep, flowing Great Lakes connecting channel. First, we developed a buoy‐less method for sampling fish eggs and...

Long-term monitoring data are difficult to obtain for high-value resource areas, particularly in remote parts of national parks. One long-used method for evaluating change uses ground-based repeat photography to match historical images of landscapes. River expeditions that documented a proposed railroad route through Grand Canyon with large-format photographs occurred in...

Holocene- to late Pleistocene-aged lava flows at Craters of the Moon National Monument and Preserve provide an ideal setting to examine the early stages of soil formation under cool, dry conditions. Transects were used to characterize the amount and nature of soil cover on across basaltic lava flows ranging in...

Airborne light detection and ranging (LiDAR) data were used to map water level (WL) and hydraulic gradients (δH/δx) in the Mackenzie Delta. The LiDAR WL data were validated against eight independent hydrometric gauge measurements and demonstrated mean offsets from − 0·22 to + 0·04 m (σ< 0·11). LiDAR‐based WL gradients...

The Eurasian freshwater tubenose goby Proterorhinus semilunaris (formerly Proterorhinus marmoratus) invaded the Laurentian Great Lakes in the 1990s, presumably via ballast water from transoceanic cargo ships. Tubenose gobies spread throughout Lake St. Clair, its tributaries, and the Detroit River system, and also are present in the Duluth-Superior harbor of Lake...

Geological effects of the 2010 Chilean tsunami were quantified at five near-field sites along a 200 km segment of coast located between the two zones of predominant fault slip. Field measurements, including topography, flow depths, flow directions, scour depths, and deposit thicknesses, provide insights into the processes and morphological changes associated...

The aim of this study was to determine the suitability of water quality in the Roanoke River of North Carolina for supporting shortnose sturgeon Acipenser brevirostrum, an endangered species in the United States. Fathead minnows Pimephales promelas were also evaluated alongside the sturgeon as a comparative species to measure potential...

Stream ecosystems harbor many secretive and imperiled species, and studies of vertebrates in these systems face the challenges of relatively low detection rates and high costs. Environmental DNA (eDNA) has recently been confirmed as a sensitive and efficient tool for documenting aquatic vertebrates in wetlands and in a large river...

Maps of irrigated areas are essential for Ghana's agricultural development. The goal of this research was to map irrigated agricultural areas and explain methods and protocols using remote sensing. Landsat Enhanced Thematic Mapper (ETM+) data and time-series Moderate Resolution Imaging Spectroradiometer (MODIS) data were used to map irrigated agricultural areas...

For more than a century, the Sangamon paleosol (the Sangamon) has been an integral part of geologic and pedologic investigations in the central United States, including the Upper Mississippi and Lower Missouri River Valleys. Compositional, pedologic, micromorphologic, stratigraphic, and age data indicate that the prominent reddish paleosol developed in silt-rich...

Nebraska's Central Platte River Valley (CPRV) is a major spring‐staging area for migratory birds. Over 6 million ducks, geese, and sandhill cranes (Grus canadensis) stage there en route to tundra, boreal forest, and prairie breeding habitats, storing nutrients for migration and reproduction by consuming primarily corn remaining in fields after...

Reliable estimates of abundance are needed to assess consequences of proposed habitat restoration and enhancement projects on freshwater mussels in the Upper Mississippi River (UMR). Although there is general guidance on sampling techniques for population assessment of freshwater mussels, the actual performance of sampling designs can depend critically on the...

Most studies of King Rail (Rallus elegans) have investigated habitat use during the nesting season, while few comparisons have been made between the nesting and brood-rearing seasons. King Rails were located during the nesting season in Missouri using repeated surveys with call playback, and systematic searches for broods were conducted...

The effects of Pleistocene cold-climate geomorphology are distributed across the weathered and eroded Mid-Atlantic Coastal Plain uplands from the Wisconsinan terminal moraine south to Tidewater Virginia. Cold-climate deposits and landscape modifications are superimposed on antecedent landscapes of old, weathered Neogene upland gravels and Pleistocene marine terraces that had been built...

Stream and reservoir stage are critical parameters in the computation of stream discharge and reservoir volume, respectively. In addition, a record of stream stage is useful in the design of structures that may be affected by stream elevation, as well as for the planning for various uses of flood plains....

The introduction of American shad from the Atlantic to the Pacific coast of North America in the late 1800’s and the subsequent population expansion in the 1980’s resulted in the amplification of Ichthyophonus sp., a Mesomycetozoean parasite of wild marine fishes. Sequence analysis of the ribosomal DNA gene complex (small...

A prolonged drought in the High Plains of Nebraska prompted the use of groundwater for cooling at the largest coal-fired power plant in the State. Prior to the drought, groundwater was used primarily for irrigation and the power plant relied exclusively on surface water stored in a nearby reservoir for...

Recent floods on the Wichita River at Wichita Falls, Texas, have reached higher stages compared to historical floods of similar magnitude discharges. The U.S. Geological Survey (USGS) has operated streamflow-gaging station 07312500 Wichita River at Wichita Falls, Tex., since 1938 and flood measurements near the location of the present gage...

The Mt. Edgecumbe Volcanic Field (MEVF), located on Kruzof Island near Sitka Sound in southeast Alaska, experienced a large multiple-stage eruption during the last glacial maximum (LGM)-Holocene transition that generated a regionally extensive series of compositionally similar rhyolite tephra horizons and a single well-dated dacite (MEd) tephra. Marine sediment cores...

Metropolitan Atlanta-September 2009 Floods The epic floods experienced in the Atlanta area in September 2009 were extremely rare. Eighteen streamgages in the Metropolitan Atlanta area had flood magnitudes much greater than the estimated 0.2-percent (500-year) annual exceedance probability. The Federal Emergency Management Agency (FEMA) reported that 23 counties in Georgia...

The continuous slope-area (CSA) method expands the slope-area method of computing peak discharge to a complete flow event. Continuously recording pressure transducers installed at three or more cross sections provide water-surface slopes and stage during an event that can be used with cross-section surveys and estimates of channel roughness to...

Avian studies conducted in the 1970s on Alaska’s Arctic Coastal Plain (ACP) indicated that coastal littoral habitats are important to Arctic-breeding shorebirds for staging prior to fall migration. However, relatively little recent, broad-scale, or quantitative information exists on shorebird use of staging areas in this region. To locate possible shorebird...