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

Nitella, Elodea, Potamogeton and mosses, provided important primary input in shallower
inlet azeas. Zooplankton consisted primarily of the rotifer Synchaeta and the crustaceans
Cyclops, Daphnia and Bosmina. Populations of zooplankton usually peaked in July.
Deeper benthic portions of the reservoir contained mostly oligochaetes and chironomids
that varied in population levels. Benthic communities in the shallower bay areas were
quite variable with the samples being dominated by chironomids and gastropods.
Macroinvertebrate densities ranged from 1,804/m2 to 14,485/ m2. Biomass ranged from
0.93 g/mZ to 25.5 g/m2. This community structure was indicative of clean water and
oligotrophic conditions.
Seven species offish were found in Ruedi Reservoir including: rainbow trout, brown
trout, brook trout, lake trout, kokanee salmon, bluehead sucker and mottled sculpin.
Native cutthroat trout were stocked in 1972 but recent surveys have not found this species
to be present. Habitat requirements for adults juveniles and spawning, of each species
were summarized. Historically brown trout have been the most abundant species.
However, numbers of brown trout have been declining over the past several years.
Fryingpan River
The study area on the Fryingpan River included the 14-mile stretch from Ruedi Dam to
the confluence with the Roaring Fork River. The chemical and physical chazacteristics in
this stretch indicated that there was quality habitat for trout. Temperature and flow were
the two primary physical components that had been altered since the completion of Ruedi
Dam. Average winter flows in the Fryingpan River were 111 cfs while unregulated
winter flows would average about 39 -cfs. Average peak summer flows were 296 cfs
while unregulated peak flows would average 1,024 cfs. Temperature seemed to be the
primary limiting factor for fisheries in this stretch. The ratio of pools and runs to riffles
was found to be 0.7. A 0.8-mile section near the confluence with Seven Castles Creek
was found to have an abundance of deep pools and runs providing excellent habitat for
adult and juvenile trout. Cobble and boulder substrates dominated most of the river.
Spawning gravels are limited to several sections in the upper portion of the river, and
locations neaz the confluences of Seven Castles Creek and Taylor Creek.
Diatoms and green algae typical of cold, rapid streams were the main components of the
' periphyton community found in the Fryingpan River. The macrophyte Ranunculus
aquaticus was found to be an important source of primary production in the sections
immediately below the dam and again seven miles below the dam. The
' macroinvertebrate community was found to vary longitudinally in the river. The
chironomid pseudodiamesa was the dominant taxa immediately below the dam, but
decreased in abundance gradually downstream. The filter-feeding caddisfly
Brachycentrus increased progressively from the dam downstream, possibly due to the
increasing abundance of fine particulate matter. Except for the noted longitudinal
variation, the macroinvertebrate community in the Fryingpan River was typical for
streams with excellent water and habitat quality.
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Fryingpan-Roaring Fork Literature Review February 27, 2002
Miller Ecological Consultants, Inc. Page 13