Publications

Priest Rapids Dam on the Columbia River produces large daily and hourly streamflow fluctuations throughout the Hanford Reach during the period when fall Chinook salmon Oncorhynchus tshawytscha are selecting spawning habitat, constructing redds, and actively engaged in spawning. Concern over the detrimental effects of these fluctuations prompted us to quantify the effects of variable...

All plants in natural ecosystems appear to be symbiotic with fungal endophytes. This highly diverse group of fungi can have profound impacts on plant communities through increasing fitness by conferring abiotic and biotic stress tolerance, increasing biomass and decreasing water consumption, or decreasing fitness by altering resource allocation. Despite more than 100 yr of research...

No abstract available

We used a Scanning Hydrographic Operational Airborne LiDAR (Light Detection and Ranging) Survey (SHOALS) system to collect high-resolution bathymetry for 33 km of the Hanford Reach. Data were used in conjunction with hydrodynamic and predictive habitat models within a GIS (Geographical Information System) framework to evaluate the effects of a varying hydrograph on juvenile fall Chinook...

We evaluated a stock for restoring runs of fall Chinook salmon Oncorhynchus tshawytscha in the Upper Klamath River basin by monitoring its development in Iron Gate Hatchery and in net-pens in the Williamson River and Upper Klamath Lake in Oregon. We transferred age-1 hatchery fall Chinook salmon to net-pens in October 2005 and age-0 fall Chinook salmon in May 2006. Indices of smolt...

Lost River sucker Deltistes luxatus and shortnose sucker Chasmistes brevirostris were listed as endangered in 1988 for a variety of reasons including apparent recruitment failure. Upper Klamath Lake, Oregon, and its tributaries are considered the most critical remaining habitat for these two species. Age-0 suckers are often abundant in Upper Klamath Lake throughout the summer months, but...

Beulah Reservoir on the north fork of the Malheur River in northeastern Oregon provides irrigation water to nearby farms and ranches and supports an adfluvial population of bull trout (Salvelinus confluentus), which are listed as threatened under the Endangered Species Act. Water management in Beulah Reservoir results in seasonal and annual fluctuations of water volume that may affect...

Acoustic transmitters implanted in green sturgeon (Acipenser medirostris) captured in rivers in California were detected by acoustic receivers deployed within and around Baker Bay. The receivers were deployed at eight locations in the Bay and adjacent navigation channels of the Lower Columbia River during a period of anticipated channel dredging. Three of the transmitters detected were...

In 2006, we collected larval Lost River sucker Deltistes luxatus (LRS), shortnose sucker Chasmistes brevirostris (SNS), and Klamath largescale sucker Catostomus snyderi (KLS) emigrating from spawning areas in the Williamson and Sprague Rivers. This work is part of a multi-year effort to characterize the relative abundance, drift timing, and length frequencies of larval suckers in this...

In the summer of 2007, we undertook an assessment of larval and juvenile sucker use of Hanks Marsh in Upper Klamath Lake, Oregon. This 1,200-acre marsh on the southeastern shoreline of the lake represents part of the last remaining natural emergent wetland habitat in the lake. Because of the suspected importance of this type of habitat to larval and juvenile endangered Lost River and...

Predation by pinnipeds, such as California sea lions Zalophus californianus, Pacific harbor seals Phoca vitulina, and Stellar sea lions Eumetopias jubatus on adult Pacific salmon Oncorhynchus spp in the lower Columbia River has become a serious concern for fishery managers trying to conserve and restore runs of threatened and endangered fish. As a result, Smith-Root, Incorporated (SRI...

This report presents the results for two sampling periods (April 2008 and July 2008) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (dissolved selenite, selenate, organoselenium), and total suspended solids were determined in water samples and total selenium...