9571

• UCREFRP Catalog Number: 9571
• Author: Miller Ecological Consultants Inc.
• Title: Fryingpan-Roaring Fork Literature Review.
• USFW Year: 2002.
• USFW - Doc Type: Fort Collins, CO.
• Copyright Material: NO

Finned, L. M. and G. L. Bennet. 1977. Fryingpan-Arkansas Fish Research
' Investigations. Colorado Division of Wildlife. Final Report.
Fryingpan River
' A variety of water quality measurements were taken in order to determine if Ruedi
Reservoir has an influence on the Fryingpan River downstream from the dam. The water
' in the river below the dam was found to be higher in pH, hardness, and conductivity than
the water flowing into the reservoir. This was presumed to be due to gypsum deposits
adjacent to the reservoir. The average summer water temperature in the river was found
' to have dropped from 14.5 C to 8.1 C after the construction of the dam. It is speculated
that these changes may slow trout growth, but may increase invertebrate production. The
loss of scouring action in the reach below the dam has caused an increase in growth of
algal mats. It has not been determined whether this algal growth has detrimental or
beneficial effects. No detrimental or beneficial effects on the biology of the river could
be ascertained.
' A review of some earlier fish population studies was presented. It was su ested that
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growth rates of brown trout in the Fryingpan River were higher than the average for
' similar rivers in that area. Growth rates for rainbow trout appeared to be normal. The
study was unable to determine the effects of planted trout on wild populations.
' Ruedi Reservoir
At this time successful reproduction of opossum shrimp, Mysis relicta, in Ruedi
' Reservoir had not been confirmed. It was noted that high population levels of opossum
shrimp had been found to reduce or eliminate populations of cladocerans. Future studies
are planned to determine the extent of competition and predation between opossum
shrimp and zooplankton.
' Nehring, R B. 1979. Evaluation of instream flow methods and determination of
water quality needs for streams in the State of Colorado. Colorado Division of
' Wildlife. Fort Collins, Colorado.
Fryingpan River
' A comparison using four methods of computer analysis to determine minimum flow for
two sites on the Fryingpan River was presented. These methods included: Single R-2
' Cross, Multiple R-2 Cross, IFG4, and the "Montana Method". The conclusions
suggested that these four methods produced similar results at both locations on the
Fryingpan River; however the "Montana Method" was less reliable on other streams.
' Minimum flow recommendations for the Fryingpan River at these two sites ranged
between 47.5 cfs and 65 cfs depending on the method that was used.

' Fryingpan-Roaring Fork Literature Review February 27, 2002
Miller Ecological Consultants, Inc. Page 9