7769

• UCREFRP Catalog Number: 7769
• Author: McAda, C. W., J. W. Bates, J. S. Cranney, T. E. Chart, W. R. Elmblad and T. P. Nesler.
• Title: Interagency Standardized Monitoring Program
• USFW Year: 1994.
• USFW - Doc Type: Summary of Results, 1986-1992 - Final Report.
• Copyright Material: NO

red shiner was typically most common in Reach 1 (12 to 7596). Sand shiner was also the third most
common species collected from the Colorado River (2 to 3096).
Other introduced species made up a small percentage of the total fish collected every year (0.2 to
5%; Tables B-11-B-14). Common carp, channel catfish, black bullhead, and green sunfish were
captured from all reaches in most years. Mosquitofish and plains killifish were usually collected in
both reaches from the Colorado River, but were never captured in the Green River. Largemouth bass
were collected 5 out of 7 years in Reach 2 and 2 years in Reach 1 of the Colorado River. They were
not collected from the Green River. Two bluegill and one northern pike were collected from the
lower Colorado River.
Native species (flannelmouth sucker, bluehead sucker, Gila spp., speckled dace, and Colorado
squawfish composed their highest percentage of the catch in 1986 (24 to 3096 of the total catch),
decreased to 2 to 21 % in 1987, but composed less than 19b of the total fish collected in all reaches in
recent years (Tables B-11-B-14). Colorado squawfish was the most common native fish collected in
all reaches except for both reaches of the Colorado River in 1986 when suckers were more abundant.
Change in CPE of the three most common introduced fishes (Figure 8) is somewhat contradictory.
In the Green River, CPE for red shiner increased in Reach 3, but decreased in Reach 4. CPE for
6
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86 87 88 89 90 91 92
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86 87 88 89 90 91 92
Year
red shiner ~ sand shiner
Figure 8.-Geometric-mean CPE (Fish per 1 mZ seined) for the three most common introduced
species collected during fall YOY Colorado squawfish monitoring-fathead minnow (circles), red
shiner (triangles), and sand shiner (diamonds).
18
86 87 88 89 90 91 92
Year
fathead minnow