Publications

We studied effects of pair status, molt intensity, and year on food selection by migrating male blue-winged teal (Anas discors) in southwestern Louisiana during springs 1990 and 1991. Diets consisted primarily of animal foods; but plant material, consisting mostly of seeds, comprised as much as 44%. There was no difference in animal food consumption by paired and unpaired males; however, the propo

No abstract available

No abstract available

Juvenile chinook salmon Oncorhynchus tshawytscha (40-50 mm total length, TL) and striped bass Morone saxatilis (30-40 mm TL) were exposed to serial dilutions (100, 50, 25, and 12.5%) of agricultural subsurface drainwater (WWD), reconstituted drainwater (RWWD), and reconstituted seawater (IO). Agricultural subsurface drainwater contained naturally elevated concentrations of major ions (such as sodi

Acute toxicity tests with reconstituted water were conducted to investigate the relationship between water hardness, salinity, and a mixture of trace elements found in irrigation drain waters entering Stillwater Wildlife Management Area (SWMA), near Fallon, Nevada. The SWMA has been the site of many fish kills in recent years, and previous toxicity studies indicated that one drain water, Pintail B

A method is given for the recovery, cleanup, and analysis of polycyclic aromatic hydrocarbons (PAHs) that have been sequestered in SPMDs (semipermeable membrane devices). SPMDs are polymeric membranes enclosing lipids, and mimic the bioconcentration process of aquatic animals. SPMDs are used as passive, in situ monitors of contamination by organic pollutants of aquatic environments. The method rep

Exposure of aquatic organisms to suspended sediments can impair growth and survival and increase bioaccumulation of sediment-associated contaminants. However, evaluation of the effects of suspended sediments and their associated contaminants on aquatic organisms has been hampered by the lack of a practical and inexpensive exposure system for conducting bioassays. We present a cost-effective system

No abstract available.

Water resources data for the 1991 water year for Iowa consist of records of stage discharge,and water quality of streams; stage, contents, and water quality of lakes and reservoirs; ground water levels and water quality of ground-water wells. This report contains records of water discharge for 118 stream-gaging stations; stage or contents for 9 lakes and reservoirs; water quality for 6 stream-gagi

This report describes procedures used by the Iowa District sediment laboratory of the U.S. Geological Survey to assure the quality of sediment-laboratory data. These procedures can be used by other U.S. Geological Survey laboratories regardless of size and type of operation for quality assurance and quality control of specific sediment-laboratory processes. Also described are the equipment, specif

The ground-water-level monitoring network in Iowa consists of 202 wells completed in the principal bedrock and surficial aquifers that supply ground water to numerous users throughout the State. The bedrock aquifers include the Cambrian-Ordovician aquifer system, the Silurian-Devonian aquifer, the Mississippian aquifer, localized Pennsylvanian aquifers, and the Dakota aquifer. The surficial aquife

Hydrologic data for a study of pre-lllinoian glacial till were collected during the 1991 water year at a site in Linn County, east-central Iowa. A hydrologic-data-collection network, consisting of a meteorological station, 22 observation wells, and a water-quality minimonitor, was installed at the site to investigate the hydraulic properties of the till. Recorders were installed on 12 of the obser