9322

• UCREFRP Catalog Number: 9322
• Author: McAda, C. W., W. R. Elmblad, T. E. Chart, K. S. Day and M. A. Trammell.
• Title: Interagency Standardized Monitoring Program
• USFW Year: 1995.
• USFW - Doc Type: Summary of Results, 1994.
• Copyright Material: NO

Results and Discussion
Distribution and Abundance
During 1994, gmean CPE was lower in reaches 1, 3 and 4 than it was in 1993 (Figure 2; Table
A-1). Catch rates in reaches 1 and 4 were the lowest observed since ISMP began in 1986. No YOY
Colorado squawfish were captured-from Reach 2 of the upper Colorado River for the second year in a
row. In the lower Colorado river, gmean CPE decreased to 0.1$3 fish/10 m2 from 0.41 in 1993.
This value is the lowest catch rate observed in Reach 1 since ISMP began; the second lowest was
.208 in 1989. As is typically the case, most YOY Colorado squawfish were captured in the lower 70
miles of the Reach, with highest catch rates between RM 20 and 60 (Figure 3; Table A-2).
In the lower Green River (Reach 3) gmean CPE decreased to 0.605 fish/10 m2 from 1.42 in 1993
(Figure 2; Table A-1). This number was slightly higher than the catch rates observed from 1990 to
1992. YOY Colorado squawfish were spread throughout Reach 3, with peaks of abundance in the
upper, middle and lower parts of the reach (Figure 3; Table A-2). Gmean CPE was 0.027 CS/10 m2
in the upper Green River (Reach 4), which was the lowest level recorded during ISMP-only 15 YOY
Colorado squawfish were collected in the entire reach. All of these fish were captured in the lower
portion of the reach.
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86 87 88 89 90 91 92 93 94
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86 87 88 89 90 91 92 93 94
Figure 2.-Geometric-mean CPE (Colorado squawfish per 10 m2 seined) for the four reaches
sampled during fall, YOY Colorado squawfish monitoring, 1986-1994. Bars represent ± 1 SE.
4
86 87 88 89 90 91 92 93 94
Year
86 87 88 89 90 91 92 93 94
Year