7058

• UCREFRP Catalog Number: 7058
• Author: Binns, N. A.
• Title: Effects of Rotenone Treatment on the Fauna of the Green River, Wyoming.
• USFW Year: 1966.
• USFW - Doc Type: Oregon State University,
• Copyright Material: NO

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These are believed to have been downstream. migrants (Peterson,
1963).
The survival time of the small carp in the live cages varied
from one to four hours after initial rotenone contact. The test carp
at station #11 did not begin to lose their equilibrium for nearly
three hours after initial exposure. After four hours, the young
carp were so weak that they were pressed together at the down-
stream end of the cage; death followed shortly. Differences in
survival duration probably were primarily due to the fish being
exposed to different concentrations of rotenone. Variations in the `- ='
natural toxic resistance of test fish may also account for some of ~°r~
..;
the differences. Adult carp in the river near station #9 were first
observed in distress 105 minutes after exposure.
After the closure of each rotenone introduction station, the
river below remained contaminated until all the rotenone from up- -
stream stations had either decomposed or dispersed downstream.
Accumulations of rotenone downstream subjected the lower sections ~'
of the river to very extended periods of contamination. For ~
example, at Green River City, rotenone was first present on
September 6 at 0100 hours; Henderson {1963) reported finding at
Ieast 0, I ppm of rotenone at about 1200 hours on September 11.
Rotenone was thus present for at least 131 hours (5-1/2 days).
Assuming a river flow of one mile per hour, the rotenone from