Publications

Sublethal physiological effects and metal residue accumulation in tissues were measured in adult and juvenile rainbow trout fed a metal-contaminated diet and/or exposed to waterborne metals for 21 d. The consumption of metal-contaminated invertebrates from the Clark Fork River, Montana, significantly affected scale loss and metal accumulation in gut tissue of adult trout. Survival, scale...

The upper Clark Fork River basin in western Montana is widely contaminated by metals from past mining, milling, and smelting activities As part of a comprehensive ecological risk assessment for the upper Clark Fork River, we measured physical and chemical characteristics of surficial sediment samples that were collected from depositional zones for subsequent toxicity evaluations Sampling...

A comprehensive field and laboratory approach to the ecological risk assessment for the Milltown Reservoir-Clark Fork River Sediments Site, a Superfund site in the Rocky Mountains of Montana, has been described in the preceding reports of this series. The risk assessment addresses concerns over the ecological impacts of upstream releases of mining wastes to fisheries of the upper Clark...

Hydrologic data were collected in the Bloody Run and Sny Magill watersheds in Clayton County, Iowa during the 1992 Water Year (October 1, 1991 to September 30, 1992) to provide data on suspended sediment and stream discharge from these watersheds. Suspended-sediment samples were collected daily during normal flow and several times during rainstorms. Stream stage was recorded continuously...

We assessed geographic variability in morphology among Yellow-headed Blackbirds (Xanthocephalus xanthocephalus) collected from breeding populations in Minnesota, North Dakota, and South Dakota in the United States and Alberta, Manitoba, and Saskatchewan in Canada during spring. Both male and female Yellow-headed Blackbirds tended to be larger in the more northern breeding populations...

No abstract available.

The effect of seasonal inundation on the decomposition of emergent macrophyte litter (Scolochloa festucacea) was examined under experimental flooding regimes in a northern prairie marsh. Stem and leaf litter was subjected to six aboveground inundation treatments (ranging from never flooded to flooded April through October) and two belowground treatments (nonflooded and flooded April to...

The objective of this study was to demonstrate a method for testing the toxicity of contaminated sediments under field conditions. An artificial sediment that matches field sediment in grain‐size distribution and organic matter content was mixed from 11 components and used as the test substrate. Clean sediments and sediments spiked with zinc (∼8,000 mg/kg) were exposed in the field on a...

No abstract available.

Composition and biomass of beds of submerged aquatic vegetation (SAV) in estuaries along the upper Texas coast were examined from bottom core and rake samples taken along 72 line transects during July–August 1987. Substrate composition, salinity, water depth, and water clarity were also measured at each sample station. Halodule wrightii was the dominant species of SAV meadows (69%...

We measured aquatic invertebrate abundance, standing stock biomass, and community production in three types of wetlands on Noxubee National Wildlife Refuge from December 1987 through April 1988. Together, Orthocyclops modestus and Daphnia pulex were the most abundant organisms collected in all habitats during both winter and spring, but each contributed little to total standing stock...

No abstract available