7956

• UCREFRP Catalog Number: 7956
• Author: Day, K. S.
• Title: Colorado Squawfish Population Trends, Upper Green River And Lower White River, Utah, 1990-1994 ‎(Draft)‎.
• USFW Year: 1995.
• USFW - Doc Type: \
• Copyright Material: NO

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if the larger fish produced in 1994, although less numerous than in most years, will have
superior survival and recruitment.
Fall monitoring for age-0 squawfish should continue in order to dampen the
effects of variability on data analysis. It is important to determine optimum conditions
for survival of YOY fish and the factors effecting this. Clearly, flows alone are not
responsible for productivity and survival. Continued monitoring is necessary to
determine the combination of factors influencing productivity. However, based on the
information collected in 1994, it may be necessary to consider adding mid-summer YOY
sampling to the ISMP. Summer-long sampling by UDWR provided insight into YOY
fish numbers and growth that would have been missed if only one fall monitoring trip
had been made. The YOY ISMP data by themselves seem to indicate little or no
squawfish production, when, in fact, the young were large enough by fall to reside in the
main channel and, therefore, avoid capture.
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LITERATURE CITED
Cranney, J. S. 1990. Interagency standardized monitoring program: Upper Green
River and lower White River, Utah. Draft Interim Report 1986-89. UT Div.
Wildl. Res., Vernal. 27p.
McAda, C. W., J. W. Bates, J. S. Cranney, T. E. Chart, W. R. Elmblad and T. P. Nesler.
1994. Interagency standardized monitoring program: Summary of results, 1986-
1992. Recovery Implementation Prog. for the -End. Fishes of. the Upper Colo.
River Basin. U. S. Fish and Wildl. Serv. Denver. 132p.
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