8096

• UCREFRP Catalog Number: 8096
• Author: American Fisheries Society.
• Title: Proceedings of the 19th Annual Meeting, Colorado - Wyoming Chapter, American Fisheries Society.
• USFW Year: 1984.
• USFW - Doc Type: March 7-8, 1984.
• Copyright Material: NO

researchers in other western states are observing this phenomenon as well (Dick
Vincent and Fred Nelson, Montana; Kerry Connell, Wyoming; Jim Johnson, Utah -
personal communications).
We do not mean to imply that the findings in this study can be applied
across the board to all streams in the intermountain west or that it contra-
dicts findings in the eastern and north central U.S. w'nere higher stream flows
increase fry survival (Latta 1965). On the contrary, low gradient streams
and streams severely impacted by upstream irrigation diversions and minimal
releases from storage reservoirs may show that augmented flows are necessary
to maintain good trout fry survival and recruitment. We have several streams
in Colorado where this is the case. What is critical is that optimum flows
should be maintained if at all possible during critical spawning, incubation,
and pre-and-post emergence periods for trout fry. These stages of the trout's
life cycle are the most vulnerable to environmental variables in most in-
stances.
LITERATURE CITED
Bovee, K. D. 1978. Probability-of-use criteria for the family Salmonidae.
Cooperative Instream Flow Service Group. Western Energy and Land Use
Team, Office of Biological Services, Fish and Wildlife Service, U.S.D.I.
Instream Flow Information Paper No. 4. FWS/OBS-78/07 80 pp.
Bovee, K. D., and R. T. Milhous. 1978. Hydraulic simulation in instream
flow studies: Theory and techniques. Cooperative Instream Flow Service
Group. Western Energy and Land Use Team, Office of Biological Services,
Fish and Wildlife Service, U.S.D.I. Instream Flow Information Paper
No. 5. 131 pp.
Brett, J. R. 1951. A study of the Skeena River climatological conditions
with particular reference to their significance in sockeye production.
J. Fish. Res. Bd. Can 8(3):178-187.
Bulkley, R. V., and N. G. Benson. 1962. Predicting year-class abundance of
Yellowstone Lake cutthroat trout. U.S. Fish and Wildlife Service,
Research Report No. 59. 21 pp.
Davis, J. A., and C. A. Carlson. 1983. The brown trout fishery in Dillon
Reservoir, Colorado. Proc. 18th Annual Meeting Colo.-6dyo. Chapter
American Fish. Soc. p. 36-47.
Drummond, R. A. 1966. Reproduction and harvest of cutthroat trout at
Trappers Lake, Colorado. Colo. Div. Game, Fish and Parks. Spec. Rep.
No. 10. 26 pp.
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