7752

• UCREFRP Catalog Number: 7752
• Author: Stanford, J. A.
• Title: Instream Flows to Assist the Recovery of Endangered Fishes of the Upper Colorado River Basin
• USFW Year: 1993.
• USFW - Doc Type: Review and Synthesis of Ecological Information, Issues, Methods and Rationale.
• Copyright Material: NO

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CD 250
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C'CI 200
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Q 150
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Figure 6. Generalized relationship between average daily flows in the Green River (Jensen
gauge: 1980-91), river temperatures ee) and the timing oflife history events of squawfish (CS),
humpback chub (He) and razorback sucker (RZ) (modified from Tyus 1990, Tyus and Karp 1991,
flow data from U.S. Geological Survey).

and duration of the peak flow events that occurred during spring runoff or other intense spates of
that year, or the year or two immediately preceding the measurements. Instream flows designed to
provide maximum access for endangered fishes to low velocity habitats must be based on long-term
measures of the relationship between peak flows and channel and backwater configuration, even in
river segments where delivery of sediments is equal to export (quasi-equilibrium systems). This is

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especially true in alluvial segments that may be aggrading, as in the Escalante Bottom and Ouray

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