9385

• UCREFRP Catalog Number: 9385
• Author: Hawkins, J.
• Title: Responses by Flaming Gorge Technical Integration Team to April 4, 2000, Minority Report from John Hawkins
• USFW Year: 2000.
• USFW - Doc Type: Flow and Temperature Recommendations for Endangered Fishes in the Green River Downstream of Flaming Gorge Dam ‎(hereafter the Flow Report.
• Copyright Material: NO

The Little Snake River is significant to endangered Colorado River fishes for
two primary reasons. First, it provides mainstream habitat for humpback chub and
Colorado pikeminnow and second, it contributes flow and sediment that maintain
nursery habitats in the alluvial reaches of the Green River. Since the closure of
Flaming Gorge Dam beneficial sediment loads have decreased 50% in the
downstream alluvial reaches of the Green River. Sediments from the Little Snake
River are critical in maintaining the active channel in alluvial reaches of the Green
River and partially ameliorate the loss of sediments in the Green River due to
Flaming Gorge Dam. Currently a high percentage of the beneficial sediment load
in the Yampa and Green rivers originates from the highly erosive soils in the Little
Snake River Basin. Approximately 77% of the Yampa River sediment load is from
the Little Snake River and downstream in the Green River, about 60% of the
sediment load at the Jensen gage is from the Little Snake River. Seasonal runoff
in the Little Snake River is early compared to the Yampa River and because flows
are unregulated, the amplitude between peak and base flows is high. Depletions
from the Little Snake River are about 11 % of the historical yield and are low
compared to most Upper Basin rivers. Additional depletions from the tributary
Savery Creek at the new High Savery Dam, Wyoming will increase annual
depletions to about 14% of the total yield of the Little Snake River.

In four years of sampling the Little Snake River between 1981 and 1995,
seventeen species of fish were caught, including ten nonnative species. However,
these nonnative species that are typically abundant and widespread in other Upper
Colorado Basin rivers were few in number and limited in distribution in the Little
Snake River; native species were more abundant and widespread than nonnatives
in all years sampled. In 1981, 64% of all individuals captured were natives; in
1988, 96% were native; in 1994, 69% were native; and in 1995, 72% were
native. The most abundant native species included flannelmouth sucker
(Catostomus latipinnis), blue head sucker (C. discobolus), and roundtail chub

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