7103

• UCREFRP Catalog Number: 7103
• Author: Grabowski, S. J. and S. D. Hiebert.
• Title: Green River Trophic Dynamics Study 1987
• USFW Year: 1988.
• USFW - Doc Type: Draft.
• Copyright Material: NO

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RESULTS AND DISCUSSION

Green River Flows

Water releases out of Flaming Gorge Dam into the Green River were fairly
well regulated in 1987 to provide previously-negotiated flow regimes
for ongoing research needs related to endangered fishes studies. Flows
out of Flaming Gorge Dam were gradually reduced from mid-June to about
mid-August, to allow quantification of size and numbers of backwaters
developing at various flows, and to determine at what flows backwater
habitat would be optimized for use by larval Colorado squawfish. Daily
average flows in the Green River from June to November are shown in
figure 2; sampling periods for the trophic dynamics study are highlighted
on the figure. Implications of the changes in river flow during a
particular sampling period and seasonally will be discussed below.

Main River

Water temperature. - Water temperature initially increased from early
June to a high in early August at Island Park, Jensen and Ouray, then
decreased steadily to the last sampling period in mid-November (fig. 3).
In most cases water temperature increased from Island Park downstream
to Ouray. However, by mid-November, main river water temperature decreased
downstream. Some ice began to appear on backwaters in November. Main
river water temperatures ranged from 4.54 to 20.81 oC at Island Park,
3.43 to 22.55 oC at Jensen, and 1~72 to 24.18 oC at Ouray during the

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