9705

• UCREFRP Catalog Number: 9705
• Author: Green River Study Plan ad hoc Committee.
• Title: Study plan for the implementation and evaluation of flow and temperature recommendations for endangered fishes in the Green River downstream of Flaming Gorge Dam.
• USFW Year: 2007.
• USFW - Doc Type: Upper Colorado River Endangered Fish Recovery Program
• Copyright Material: NO

GREEN RIVER STUDY PLAN

24

February 2, 2007

Table 2. Continued.

Primary Studies Topic Not
Addressed by
Anticipated Effects and Uncertainties (Hypotheses) That Address Studies (information
Hypothesis needs)
Nonnative Fishes in Reach 1 (continued)
U2. The response of nonnative fish populations to the spring . Project 115 . Nonnative fish life
peak flows (U.S. Fish and Wildlife Service 2005). history components
affected by flows
(e.g., spawning
locations, timing,
temperature, fish
concentration areas).
U4. The effect of base flows and release temperatures on . Project 115 . Nonnative fish life
nonnative fish populations (U.S. Fish and Wildlife Service . Project 8 history components
2005). . Project 19 affected by flows.
Nonnative Fishes in Reach 2
U21. The effect of base flows on nonnative fish populations . Project 138 . Nonnative fish life
(Muth et al. 2000). . Project 144 history components
. Project 123 affected by flows.

The following three resource categories represent the most important Issues for
evaluating the flow and temperature recommendations.

1. Floodplain inundation for larval entrainment, rearing, and subsequent movement of
subadult razorback suckers into the mainstem in Reach 2.

2. Backwater formation and maintenance for the rearing of young Colorado pikeminnow.

3. Nonnative fish management in Reach 1 and upper Reach 2.

The order of the three resource categories does not imply prioritization or greater
importance of one group of studies over another. Integration of these study components provides
a more comprehensive strategy for evaluating the flow and temperature recommendations that is
more closely allied to species recovery. Because some anticipated effects and uncertainties are
either closely linked, redundant, or overlapping, isolating a single hypothesis or study risks
fragmentation that could inadvertently exclude important ecological issues vital to species
recovery .

It should be noted that the identified categories and studies are necessary for evaluating
the flow and temperature recommendations, and are not necessarily inclusive of all of the most
important issues and studies necessary for recovery of the four endangered fish species in the
Upper Basin. Other Recovery Program actions are addressing those issues not related to the flow
and temperature recommendations (Figure 1). The ultimate goal of all of the Recovery Program