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Feasibility of Using 3-D Acoustic Telemetry to Assess the Response of Resident Salmonids to Strobe Lights in Lake Roosevelt, Washington

An entrainment study at Grand Coulee Dam indicated that 200,000 - 600,000 kokanee were entrained, primarily at the 3rd powerhouse, during a 40-month time period. Following the recommendations of the Independent Scientific Review Panel, research was initiated to investigate a strategy to reduce entrainment by using strobe lights to repel salmonids More...

  • Image of kokanee (Oncorhynchus nerka)

Bioaccumulation of Mercury by Fish and Fish-forage Organisms in Camp Far West Reservoir, Yuba and Placer Counties, California

Mercury contamination from historic gold mining operations is widespread in many rivers, lakes, and reservoirs on the western slopes of the Sierra Nevada. A multidisciplinary investigation by USGS is attempting to better understand mercury dynamics and to identify hot spots within Camp Far West Reservoir in order to determine if remediation More...

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Persistence of organochlorine chemical residues in fish from the Tombigbee River (Alabama, USA): Continuing risk to wildlife from a former DDT manufacturing facility

Organochlorine pesticide and total polychlorinated biphenyl (PCB) concentrations were measured in largemouth bass from the Tombigbee River near a former DDT manufacturing facility at McIntosh, Alabama. Concentrations of DDT isomers in McIntosh bass remained unchanged from 1974 to 2004 and were four times greater than contemporary concentrations More...

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Near-Shore Habitat Use by Endangered Juvenile Suckers

The objectives of this study are 1) to determine how and when juvenile suckers use near-shore habitat with emergent vegetation, 2) determine how the distribution and abundance of juvenile suckers varies between near shore and offshore areas as well as between different areas of the lake over time, 3) determine if water quality conditions affect More...

  • Juvenile sucker captured in emergent vegetation.

Cellular and Genetic Tracers of Transport Time in Groundwater Systems

Artificially maintained water levels within the lake and stresses placed upon the aquifer by well withdrawals facilitate movement of water from the lake into the local ground water system, potentially allowing contaminants to enter the aquifer from the lake. This raises national concern because similar lakeside settings exist throughout the United More...

  • Diatom image of the species Cymbella tumida.

Ecological Genetics of Lake Clark Sockeye Salmon (Oncorhynchus nerka)

Ecological Genetics of the Lake Clark Sockeye Salmon (Oncorhynchus nerka) characterizes the population structure and genetic diversity. This issue overview aids managers in defining and prioritizing conservation units of sockeye salmon within Lake Clark National Park and Preserve.

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Rehabilitation of Salamander Populations in High Mountain Lakes, Mount Rainier National Park

The National Park Service has stated that declining amphibian populations are the top priority for research in the National Park System. Salamanders are a native vertebrate predator in high-mountain lakes throughout the western US, especially in many small lakes naturally barren of fish. This issue overview demonstrates the potential for using More...

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Distributions and Relative Abundances of Amphibian Taxa Associated with Palustrine Vegetated Wetlands, Ponds, Lakes, Streams and Rivers in Mount Rainier National Park

Little is known about the amphibian taxa associated with streams, lakes, ponds, and wetlands in Mount Rainier National Park (MORA). This issue overview addresses the concerns about the possible impacts of introduced trout on amphibian taxa, and park management's interest in documenting current distribution and abundance of amphibian taxa in the More...

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Ecological Impact of Introduced Trout on Native Aquatic Communities in Mountain Lakes

Fish introductions have been implicated in the disappearance of amphibian communities and in the alteration of zooplankton communities. Furthermore, the presence and abundance of amphibian larvae and zooplankton in mountain lakes are directly related to nutrient concentrations in the aquatic environment, as well as enhancement to recreational More...

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Mercury Contamination in Fillets of Selected Sport Fishes from Lake Natoma

Lake Natoma, an 8,760 acre-feet reservoir on the American River, is managed by the U.S. Bureau of Reclamation (USBR) for multiple uses that include fishing and other water-based recreation. Preliminary results from 22 fish samples collected in Lake Natoma during August 2000 indicate that the mercury content may approach or exceed guidelines for More...

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Assess Current and Potential Salmonid Production in Rattlesnake Creek

With the proposed removal or laddering of Condit Dam scheduled for 2006, Rattlesnake Creek has high potential to support reintroduced or naturally colonizing populations of salmon and steelhead. Research on resident trout populations will serve as a surrogate for an initial evaluation of limiting factors to salmon and steelhead production in the More...

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Heritability of Disease Resistance and Immune Function in Chinook Salmon, with Special Emphasis on Broodstock Culling to Control Bacterial Kidney Disease

Many diseases of trout and salmon persist in our cultured fish stocks today, despite improvements in fish culture practices and years of research on vaccines and chemotherapeutants. An excellent example is bacterial kidney disease (BKD), caused by the bacterium Renibacterium salmoninarum. Infections by R. salmoninarum are considered by many to be More...

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