9301

• UCREFRP Catalog Number: 9301
• Author: Wydoski, R. S.
• Title: Green River Fishes and Invertebrates.
• USFW Year: 1967.
• USFW - Doc Type: Logan, UT.
• Copyright Material: NO

70
INTRODUCTION
1
Before Flaming Gorge Dam in northeastern Utah was closed, a fish control
program was carried out on approximately 450 miles of the.Green River and its
tributaries to suppress non-game fish populations and allow stocked trout to
survive and provide satisfactory sport fishing in the new reservoir and tail-
waters. Accordingly, a total of 21,495 gallons of 5-percent rotenone was
introduced into the Green River at several stations beginning at Pinedale,
Wyoming on September 4, 1962, and concluding at a site located 7 miles up-
stream from the Flaming Gorge Dam site on September 7, 1962. To detoxify the
rotenone and protect the native fishes downstream in Dinosaur National Monu-
ment, potassium permanganate was released at Browns Park, 36 miles below the
last rotenone station and 16 miles upstream from Dinosaur National Monument.
In spite of the precautionary measure, an accidental kill of unknown numbers
of fish and aquatic insects occurred in the Monument, apparently the result
of an undetermined amount of toxic water passing downriver. The anticipated
benefits of the eradication program have been realized in F amin& Gorge
Reservoir, and in 1965, 191,619 anglers fished 621,799 hours and caught
?- -?_ - 57--rainbow trout,- ____ almo gairdneri! (Eisermanet al9 1967).
The Secretary of the Interior, Stewart L. Udall, reviewed the Green River
Fish Eradication Program March 25, 1963, and asked the National Park Service
and the Bureau of Sport Fisheries and Wildlife to undertake fish population
studies in Dinosaur National Monument to determine the extent of species
and population impairment caused by the rotenone and to plan a longer range
research project which would assess the changes on habitat and populations
in Dinosaur National Monument brought about by the closing of Flaming Gorge
Dam.
In response to this directive,-the-Bureau of _Sport_Fisheries_.ansL Wild-11 life assigned the problem to the Utah Cooperative Fishery Unit to be financed
under Section 8 of the Colorado River Storage Project Act. The objectives
of these studies were (1) to study changes in the environment and changes
in aquatic life brought about through modification of stream flows as a
result of the construction and operation of Flaming Gorge Dam, and (2) to
determine existing populations-of -fish and other aquatic forms -in--the-,Green
River from Flaming Gorge Dam to Ouray, Utah, (a distance of 166 river miles)
and to follow changes with particular reference to the fish control project.
Emphasis was placed upon studies of indigenous fishes in Dinosaur National
Monument, the invertebrate forms which make up major portions of the natural
food of fishes, and physical and chemical characteristics of the aquatic eco-
system.
Field studies were begun in the summer of 1963 and were supervised by
the late Dr. Donald R. Franklin, former Unit Leader, Utah Cooperative Fishery
Unit, until the time of his death February 6, 1966. Studies were completed
in September, 1966, under the direction of the present Unit Leader, Utah
Cooperative Fishery Unit. _ _In,?ad_dition _to the. Bureau, of__Sport_Fishe.ries_ and
Wildlife, other agencies cooperating in the present studies included the
National Park Service, Utah Department of Fish and Game, Colorado Department
of Game, Fish, and Parks, and Utah State University. Two graduate students
at Utah State University studied selected phases of the overall project for
thesis problems. One was a Master's thesis, "Distribution of Macroinverte-