WSP07684

• File Number: 8240.200.10.B
• Description: UCRBRIP Annual Report
• Basin: Colorado Mainstem
• Date: 12/22/1997
• Author: UCRBRIP
• Title: 1997 Annual Reports Package Part 3
• Water Supply Pro - Doc Type: Publication

)

The 103 preserved Colorado squawfish were captured in all four months but
predominately in July (29 specimens) and August (66 specimens). The two June
specimens are yearlings measuring 33 and 55 mm total length. The July through
September squawfish, all young-of-the -year, measured 12-50 mm and averaged of
16,26, and 34 rom, respectively through those months.
The six preserved razorback sucker (RZ and RZ?) were captured in June and July, and
range in size from 14-29 mm TL (mean of22 rom). The identity of the 14-mm
specimen in a July 23 collection is particularly questionable; morphologically it can't
be distinguished from an extreme pigmental form of blue head sucker.

The 42 preserved chub were captured in all four months but predominately June (31
specimens) and July (8 specimens) and measure 9-43 mm TL. All but the 43-rom
July specimen are young-of-the-year. Mean length progressed from 13 rom in June to
21 mm in July (exclusive of the 43-mm yearling), 32 mm in August, and 40 rom in
September. All but two chub with countable fin rays had 9 dorsal and 9 anal fm rays
and are most likely roundtail chub.

(b) 1995 Green River Light-trap Collections.

This set consists of 77 preserved collections taken from the lower Green River. In all,
the collections contained 11,403 specimens, 11 of which were Colorado squawfish
and 5 of which were razorback sucker (including one tentative identification). The
fish have not yet been cataloged into the LFL Collection. For more details, see final
report for Project 34 (razorback sucker spawning and larval distribution).

(c) 1995 Green River Drift-net Collections.
This set consists of216 preserved collections and includes 16 Colorado squawfish.
Fish other than Colorado squawfish were not identified or otherwise processed except
for storage. The fish have not yet been cataloged into the LFL Collection. For more
details, see final report for Colorado River Recovery Implementation Program Project
32 (Bestgen, K. R., R. T. Muth, and M. A. Tranunel. 1997. Downstream transport of
Colorado squawfish larvae in the Green River drainage: temporal and spatial variation
in abundance and relationships with juvenile recruitment).

(d) 1996 Green River Drift-net Collections.
This set consists of 195 preserved collections and includes 45 Colorado squawfish.
Fish other than Colorado squawfish were not identified or otherwise processed except
for storage. The fish have not yet been cataloged into the LFL Collection. For more
details, see fmal report for Colorado River Recovery Implementation Program Project
32 (Bestgen, K. R., R. T. Muth, and M. A. Tranunel. 1997. Downstream transport of
Colorado squawfish larvae in the Green River drainage: temporal and spatial variation
in abundance and relationships with juvenile recruitment).

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