6010

• UCREFRP Catalog Number: 6010
• Author: Binns, A., et al.
• Title: The Planning, Operation, and Analysis of the Green River Fish Control Project.
• USFW Year: 1964.
• USFW - Doc Type: \
• Copyright Material: NO

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The survival time of the small carp in the live cages varied from one
to four hours after initial rotenone contact. These differences may have been
due to variations in the strength of rotenone fronts moving from station to
station. In other words, fish at one location tnay have been exposed to
an initial contact of relatively high concentration while fish at another
location may not have been exposed to an equivalent concentration until some-
time after initial contact was made. Differences in resistability of test
fish might also account for some of the variations in mortality-time requirements.
All test fish, except the control fish above Green River Station 1, were dead
when the live cages were removed from the river after the treatment.
The chemistry of the river changed as the river water flowed down-
stream through strata with different chemical and physical characteristics,
and most of the maximums for the various measurements were recorded from the
lower river. Except for the water temperatures recorded during the treatment,
no water chemistry data was obtained below Station 14. Minimum-maximum water
temperatures recorded during the treatment were 52° and 64° Fahrenheit, respect-
ively. Daytime water temperatures in the lower river section ranged from
65° to 67° Fahrenheit. Temperatures taken one week before treatment ranged
from 50° to 61° Fahrenheit while the range of temperatures taken one week after
treatment was from 52° to 61° Fahrenheit. Methyl orange alkalinity, measured
as ppm CaCO , showed a gradual increase with time and progression downstream.
Over the th~ee-week period, minimum readings went from 91 ppm to IOO ppm while
the maximum readings changed from 135 ppm to 1~+2 ppm.
The pH of the river varied from 7.8 to 8.6 during the three-week
period. Mirror increases in pH with the time were noted at several different
points on the river, but much of the variation was due to the location of the
checking point on the r~:i.ver, There w~~s i.~o evidence to indic~~te that -the water
chemistry was affected by the treatment.
A tentative checklist of fishes killed during the treatment is
presented in Table ~+. Mountain whitefish, Core_gonius williamsoni and flannel-
mouth suckers, Catostomus latipinnis, were the predominant species of fish
in the river. The whitefish were most abundant in the upper sections of the
river, especially in the New Fork River, while the suckers were predominant
below Green River City.
In addition, a two-man crew traveled down the river from drip stations
19 and 21 with the toxicant front. Other areas searched included Hideout
Canyon, the damsite, Little Hole, and the upper portions of Brown's Park.
Trout were found to be extremely infrequent in the Green River above the dam
and totally lacking below. The few observed above the dam are thought to
-be recruitment from treatment of tributary streams and from natural movement
of the fish down the tributaries into the Green River. Five squawfish were ~
taken during the work. No squawfish were found above the dam diversion
tunnel. The bonytail or Colorado chub, Gila robusta, was-numerous but no
humpback chub, Gila cypha, were collected.
In order to obtain an estimate of the number and weight of fish
killed per unit of stream, a crew of four men was assigned to make spot
counts and measurements of dead fish as the rotenone moved downstream. This
plan was abandoned during the first day when the salvage activities of the
multitude of onlookers made it impossible to get unbiased samples, and no
estimate of fish production in the river was obtained. A large number of fish