9692 ‎(2)‎

• UCREFRP Catalog Number: 9692
• Author: Tyus, H. and Haines
• Title: Biology of Young Colorado Squawfish
• USFW Year: n.d.
• USFW - Doc Type: 81-89
• Copyright Material: YES

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82 TYUS AND HAINES
TABLE I.-Catch (CPUE, fish/100 m2) of age-O Colorado squawfish and effort (E, 100s of m2 seined), upper
Green River basin, 1979-1988. A-G = sampling strata.
Year, catch Green River strata Yampa
and effort A B C D E F G River
.July-August
1981
CPUE 12.3 27.4 2.0 1.9 2.9 14.1 0.0 1.7
E 1.9 0.8 1.0 1.6 0.7 1.3 1.1 5.8
1984
CPUE 2.4 0.0 4.6 2.7 7.2 1.9
E 2.1 0.7 1.7 2.2 4.7 1.1
1985
CPUE 33.2 5.8 0.0 3.6 16.6 66.5 62.9 0.0
E 2.4 0.9 1.1 1.4 1.2 1.6 0.6 0.6
1986
CPUE 118.6 23.7 6.4 12.5 3.3 0.0
E 1.9 4.1 0.3 0.5 0.3 0.2
1987
CPUE 80.9 12.2 1.1 10.8 1.1 9.1
E 20.0 5.3 9.8 45.6 0.9 1.1
1988
CPUE 47.6 55.9 6.1 15.9 2.1 0.0
E 1.9 1.0 0.2 1.5 1.0 2.3
September-October
1979
CPUE 33.0 19.8 6.1 21.5 10.9 24.8 0.0
E 13.9 12.2 9.7 11.0 14.6 17.9 6.4
1980
CPUE 75.3 42.2 24.3 9.3 11.0 13.3 3.5 0.1
E 12.1 1.9 1.1 5.4 14.2 20.2 9.2 9.9
1981
CPUE 13.0 2.2 22.7 1.8 0.0 22.7 0.2 0.0
E 8.9 8.3 3.7 5.6 2.6 11.4 15.9 5.6
1982
CPUE 9.1 1.1 0.0 3.8 9.7 27.3 0.0
E 15.6 7.5 2.0 4.8 8.4 14.3 7.5
1983
CPUE 4.1 0.5 0.0 0.5 0.2 <0.1
E 11.5 6.0 2.1 6.2 15.6 25.5
1984
CPUE 0.0 1.3 0.0 0.7 2.4 0.3 0.0
E 2.0 1.6 1.6 4.1 6.8 19.6 3.5
1985
CPUE 9.2 2.1 0.0 1.4 4.6 1.5 0.0
E 14.9 7.5 2.5 7.1 7.5 16.2 4.3
1987
CPUE 12.7 0.0 1.0 0.3 1.6 2.0 0.0
E 11.3 4.0 2.0 3.3 5.6 21.3 1.6
1988
CPUE 45.3 24.7 7.2 4.4 16.8 2.7 0.0
E 23.1 11.4 6.8 12.4 13.7 22.2 4.6
(range, 20-74 d) after maximum flows, and larvae stream (Figure 2). One concentration occurred be-
in the lower Green River hatched about 40.0 d tween RK 335 and 450, or about 150 km down-
(range, 8-55 d) after maximum flows. Hatching stream ofYampa Canyon spawning area; another
occurred at mean water temperatures of about was about 150 km downstream of Gray Canyon
22.90C (range, 19-260C) in the Green River for (between RK 32 and 160). However, as in the July
the years 1981 and 1984-1988. and August catches, highest numbers occurred ei-
Postlarvae captured from late September to Oc- ther in the upper or lower Green River, depending
tober were also concentrated in two areas, but fish on the year sampled. Higher catches generally oc-
abundance was reduced and the location of each curred in low-gradient reaches, including strata A,
concentration area was shifted about 20 km down- B, E, and F (mean, 12.4/100 m2 seined). Higher-