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Publications

Publications from USGS science centers throughout the Southeast Region.

Filter Total Items: 10362

Population biology of the Florida manatee: An overview Population biology of the Florida manatee: An overview

In the following overview we discuss progress toward meeting the three objectives of the 1992 workshop: to provide a synthesis of existing information about manatee population biology; to evaluate the strengths and weaknesses of current data sets and approaches to research on manatee population biology; and to provide recommendations for research. We discuss progress in six topics that...
Authors
Thomas J. O'Shea, B.B. Ackerman

Contraction scour at a bridge over Wolf Creek, Iowa Contraction scour at a bridge over Wolf Creek, Iowa

Contraction scour at the State Highway 14 bridge over Wolf Creek in south-central Iowa was caused by a large flood on September 14 and 15, 1992. The bridge is a 30.5-m, single-span steel structure supported by vertical-wall concrete abutments with wingwalls. Approximately 6 meters of scour resulted from the flood. The peak discharge was estimated by water-surface profile analysis to be 2...
Authors
Edward E. Fischer

Influence of fluoride on aluminum toxicity to Atlantic salmon (Salmo salar) Influence of fluoride on aluminum toxicity to Atlantic salmon (Salmo salar)

Atlantic salmon (Salmo salar) alevins were exposed to various aluminum (0–4700 μg/L) and four fluoride (0–500 μg/L) concentrations at two pH values (5.5 and 6.5) for 4- and 30-d periods. In the 4-d tests, aluminum with fluoride was less toxic at pH 6.5 than at pH 5.5, whereas without fluoride, pH had no effect. In the 30-d test, mortality in all treatments was 17–21% at pH 5.5, but only...
Authors
Steven J. Hamilton, Terry A. Haines

Can Dugongs Survive in Palau? Can Dugongs Survive in Palau?

In August 1991 we surveyed dugongs Dugong dugon in the coastal waters of Palau using methods similar to aerial surveys conducted in 1977, 1978 and 1983. Twenty-six dugongs (including four calves) were seen, a count within the range obtained previously. The rate at which dugongs were seen per unit flight-time was lower than for any of the other surveys, despite the observers being more...
Authors
H. Marsh, G. B. Rathbun, T. J. O'Shea, A.R. Preen

Trends and patterns in mortality of manatees in Florida, 1974-1991 Trends and patterns in mortality of manatees in Florida, 1974-1991

Abstract not supplied at this time
Authors
B.B. Ackerman, S.D. Wright, R. K. Bonde, D.K. Odell, D.J. Banowetz
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