7145

• UCREFRP Catalog Number: 7145
• Author: Inslee, T. D.
• Title: Spawning of Razorback Suckers
• USFW Year: 1981.
• Copyright Material: NO

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REACH 1
85
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ss? 1 r as 84
I 82 ?? I
10 20 30 40 50 60 70 80
MAXIMUM-ANNUAL DISCHARGE (CFS X 1000)
Figure 3. Plot of geometric-mean catch-per-effort (C/E) versus maximum-
annual discharge for post-larval Colorado squawfish collected during
October, Colorado River, 1982-1988. Lines indicate ± 1 standard error.
Figure from McAda and Kaeding (1989). Reach 1 includes Colorado river-
miles 0-110 (confluence with the Green River to lower end of Westwater
Canyon).
rounding to the nearest 10,000 cfs, therefore recommended a peak discharge
of 30,000-40,000 cfs (measured at the State line) to maximize production
of young Colorado squawfish.
New Information
We similarly analyzed data on larvae collected during July and August and
post-larval fish collected during late September from three river reaches
in the Grand Valley: the 15-mile reach, the lower 18-mile reach, and the
Gunnison River downstream of the Redlands Diversion. Sampling methods were
previously described in Osmundson and Kaeding (1989) and U.S. Fish and
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