9569

• UCREFRP Catalog Number: 9569
• Author: Valdez, R. A.
• Title: Synthesis of Winter Investigations of Endangered Fish in the Green River Below Flaming Gorge Dam.
• USFW Year: 1994.
• USFW - Doc Type: 18-11,
• Copyright Material: NO

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SYNTHESIS OF GREEN RIVER AND YAMPA RIVER STUDIES
Two recent investigations in the upper Colorado River basin described the effect of
fluctuating flows and ice dynamics on fish activity and habitat under winter conditions.
Valdez and Masslich (1989) used radiotelemetry to describe movement and habitat use by
adult Colorado squawfish and razorback suckers in the Green River, between Echo Park
(RM 345), Colorado, and Ouray (RM 248), Utah, from December through March 1986-87
(Winter 1) and 1987-88 (Winter 2). Wick and Hawkins (1989) conducted a similar,
concurrent investigation with radiotagged adult Colorado squawfish in the Yampa River,
from Lily Park (RM 51) to Morgan Gulch (RM 105), Colorado (Figure 1). Locations cited
in this report for the Green River are in river miles (RM) from the confluence of the
Colorado River in Canyonlands National Park, Utah. Yampa River locations are referenced
by river mile from the confluence of the Green River in Echo Park, Dinosaur National
Monument, Colorado.

River Hvdrolo2V And Ice Conditions

Green River

Hvdrology
Average and maximum flows of the Green River, and volume released from Flaming

Gorge Dam, were higher the first year of the investigation, 1986-87. For the water year 1987

(October 1, 1986 - September 30, 1987), average, maximum, and minimum daily discharges

near Greendale (0.5 miles below Flaming Gorge Dam) were 2,220; 4,030; and 742 cfs (63,

114, and 21 cms), respectively. For the water year 1988 (October 1, 1987 - September 30,

1988), average, maximum, and minimum daily discharges were 1,672; 3,280; and 860 cfs (47,