Publications
Read publications and other informational products to learn more about USGS science occurring in the Mississippi Basin.
Filter Total Items: 5583
Genetic variation in male Yellow-headed Blackbirds from the northern Great Plains Genetic variation in male Yellow-headed Blackbirds from the northern Great Plains
Electrophoretic differences at 15 presumptive loci were used to assess allelic frequencies, heterozygosities, and polymorphism for male Yellow-headed Blackbirds (Xanthocephalus xanthocephalus) collected in east-central Alberta, north-central North Dakota, and east-central South Dakota. Five loci were polymorphic and mean heterozygosities ranged from 0.119 to 0.133. Significant...
Authors
Daniel J. Twedt, William J. Bleier, George M. Linz
Comparison of algorithms for replacing missing data in discriminant analysis Comparison of algorithms for replacing missing data in discriminant analysis
We examined the impact of different methods for replacing missing data in discriminant analyses conducted on randomly generated samples from multivariate normal and non-normal distributions. The probabilities of correct classification were obtained for these discriminant analyses before and after randomly deleting data as well as after deleted data were replaced using: (1) variable means...
Authors
Daniel J. Twedt, D.S. Gill
Hydrologic data for a study of pre-Illinoian glacial till in Linn County, Iowa, water year 1991 Hydrologic data for a study of pre-Illinoian glacial till in Linn County, Iowa, water year 1991
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...
Authors
P.R. Bowman
Disappearing coastal wetlands Disappearing coastal wetlands
No abstract available.
Authors
James B. Johnston, Donald W. Field, Anthony J. Reyer
The use of freshwater and saltwater animals to distinguish between the toxic effects of salinity and contaminants in irrigation drain water The use of freshwater and saltwater animals to distinguish between the toxic effects of salinity and contaminants in irrigation drain water
Irrigation drain waters entering Stillwater Wildlife Management Area (SWMA) in south-western Nevada contain elevated levels of salinity and several inorganic contaminants (As, B, Cu, Li, Mo, and Sr). Mortalities of fish and waterfowl at the management area are believed to be associated with the poor water quality of the drains. The objective of the present study was to use fresh-water...
Authors
Christopher G. Ingersoll, F.J. Dwyer, S.A. Burch, M.K. Nelson, D.R. Buckler, J. B. Hunn
Fossil sea turtles from the early Pliocene Bone Valley Formation, central Florida Fossil sea turtles from the early Pliocene Bone Valley Formation, central Florida
No abstract available.
Authors
C.K. Dodd, G.S. Morgan
The boulder darter: a conservation challenge The boulder darter: a conservation challenge
Abstract not supplied at this time
Authors
N.M. Burkhead, J.D. Williams
Dispersal of exotic species from aquaculture sources, with emphasis on freshwater fishes Dispersal of exotic species from aquaculture sources, with emphasis on freshwater fishes
Abstract not supplied at this time
Authors
W.R. Courtenay, J.D. Williams
Acute toxicity testing of sediments Acute toxicity testing of sediments
No abstract available.
Authors
Pasquale F. Roscigno, Arthur V. Stiffey, W. David Burke, Diane K. Arwood
Selenium and other elements in freshwater fishes from the irrigated San Joaquin Valley, California Selenium and other elements in freshwater fishes from the irrigated San Joaquin Valley, California
Arsenic (As), chromium (Cr), mercury (Hg), and selenium (Se) were measured in composite whole-body samples of five fishes — bluegill (Lepomis macrochirus), common carp (Cyprinus carpio), mosquitofish (Gambusia affinis), largemouth bass (Micropterus salmoides), and Sacramento blackfish (Orthodon microlepidotus) — from the San Joaquin River system to determine if concentrations were...
Authors
M. K. Saiki, M.R. Jennings, T.W. May
Availability and quality of water from the alluvial, glacial-drift, and Dakota aquifers and water use in southwest Iowa Availability and quality of water from the alluvial, glacial-drift, and Dakota aquifers and water use in southwest Iowa
A ground-water resources investigation was conducted in southwest Iowa to describe the availability, quality, and use of water from the alluvial, glacial-drift, and Dakota aquifers in a nine-county area. Historical water quality was examined for each aquifer, and water samples were collected for major ions, trace metals, radionuclides, and selected pesticides. Selected aspects of surface...
Authors
R.E. Hansen, C. A. Thompson, P. E. Van Dorpe