WSP03461

• File Number: 8240.200.40.J
• Description: Colorado River Basin Threatened-Endangered Species - UCRBRIP - Yampa River - Environmental Studies
• State: CO
• Basin: Yampa/White
• Water Division: 6
• Date: 9/1/2004
• Author: USFWS
• Title: Management Plan for Endangered Fishes in the Yampa River Basin - Volume I -Environmental Assessment - USFWS - 09-01-2004
• Water Supply Pro - Doc Type: Report/Study

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5, Ensure adequate protection from diseases and parasites,
6. Regulate nonnative fish releases/escapement into the main river, floodplain, and tributaries.
7. Control problematic nonnative fishes as needed.
8. Minimize the risk of increased hybridization among Gila spp.
9. Minimize the risk of hazardous-materials spills in critical habitat.
10. Provide for the long-term management and protection of populations and their habitats
beyond deli sting (i.e., conservation plans),

Colorado pikeminnow (Ptychocheilus lucius)

The Colorado pikeminnow is the largest member of the minnow family (cyprinidae) in North
America. Adult pikeminnow may grow up to 6 feet in length and weigh as much as 80 pounds,
Wild, reproducing populations occur in the Green River subbasin, including the Yampa River, and
in the Colorado River subbasin of the Upper Colorado River Basin (i,e" upstream from Glen Canyon
Dam). Small numbers of wild individuals also exist in the San Juan River subbasin, although their
reproduction is limited. The species was extirpated from the Lower Colorado River Basin in the
1970's, but has been reintroduced into the Gila River subbasin, where it exists in small numbers in
the Verde River.. Geographic distribution of the Colorado pikeminnow is shown in Figure 5,
Table 2 describes its current distribution in the Green River subbasin (USFWS 2002c).

Table 2. Distribution of Colorado pikeminnow within the Green River subbasin

River Occupied HabitatlRivermiles Limits of Distribution
Green Lodore Canyon to Colorado Releases from Flaming Gorge Dam have
River confluence (360 RM) been warmed and species has naturally
expanded upstream into Lodore Canyon;
species distributed downstream to
Colorado River confluence.
Yampa Craig, CO, to Green River Present distribution similar to historic.
confluence (141 RM)
Little Snake Wyoming to Yampa River Habitat is marginal; flows are reduced;
confluence (50 RM.) historic distribution unknown.
White Taylor Draw Dam to Green River Upstream distribution blocked by Taylor
confluence (62 RM) Draw Dam,
Price Lower 89 RM above Green River Streamflow reduced; barriers occur above
confluence current distribution.
Duchesne Lower 6 RM above Green River Streamflow reduced; barriers occur above
confluence current distribution.

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The Colorado pikeminnow is a long-distance migrator; moving hundreds of miles to and from
spawning areas. Adults require pools, deep runs, and eddy habitats maintained by high spring flows.
These high spring flows maintain channel and habitat diversity, flush sediments from spawning
areas, rejuvenate food production, form gravel and cobble deposits used for spawning, and
rejuvenate backwater nursery habitats. Spawning occurs after spring runoff at water temperatures
typically between 18 and 230C. After hatching and emerging from spawning substrate, larvae drift

Management Plan for Endangered Fishes in the Yampa River Basin

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