9315

• UCREFRP Catalog Number: 9315
• Author: Harvey, M. D. and R. A. Mussetter.
• Title: Evaluation of the Required Frequency of Bar Forming Events and 2-Dimensional Hydrodynamic Modeling at Colorado Squawfish Spawning Sites in the Lower Yampa Canyon, Colorado.
• USFW Year: 1996.
• USFW - Doc Type: Fort Collins.
• Copyright Material: NO

SYSTEMATIC DATA COLLECTION AND RESEARCH (SDCR)
The SDCR element of the Flaming Gorge Investigation is a package of
closely related research and monitoring programs which will be
conducted annually throughout the five years of the Flaming Gorge
Flow Investigations. The SDCR is composed of four elements which
directly assess effects of the yearly and seasonal operation of
Flaming Gorge Dam on annual reproduction and recruitment of fishes
in the Green River system. The four elements include,
reproduction, survival of Age 0 fish to fall, overwinter survival
of young fish, and links between recruitment of young fish and
recruitment to adult stocks. The Interagency Standardized
Monitoring Program (ISMP) provides for collection of adult and
young- of - the-year fish, but concurrent, long-term information on
annual migrations and spawning success is also required to provide
information on the interaction between native and non-native fish
populations and hydrologic events. SDCR studies were designed to
supply additional information not available from the ISMP.
Research programs within SDCR include collection of long-term data
on spring movements and migrations to spawning locations, spawning,
larval drift, and age-0 and age-1 recruitment. Data collected in
the SDCR portion of the Flaming Gorge investigations is impcrtant
in that it provides a consistent year to year index of fish
abundance and population structure against which environmental
changes such as altered flows can be measured. SDCR provides a
tool by which the overall effect of recommended flows on the native
and non-native fish fauna can be measured.
Assu=tions Considered in Planning the SDCR Effort
- Framework of the SDCR effort needs to be sufficiently simple
to allow for continuity over time, flexibility as information
is gathered, and collection of sound, quantifiable data
covering important life-history stages. Consideration was
given to the ability to link new data with existing data and
information generated from ISMP and other studies.
A critical issue is the need to establish links between
reproduction, recruitment of young fish, recruitment to adult
stocks, status of populations, and how hydrologic conditions
affect life-history parameters.
Because state of knowledge of the life history of Colorado
squawfish is relatively high, compared to razorback sucker and
humpback chub, SDCR studies should initially focus on Colorado
squawfish. As knowledge of the life history of razorback
sucker and humpback chub increases, the SDCR effort could be
modified/expanded to include these species.
There are two main Colorado squawfish spawning areas in the
Green River system (i.e., lower Yampa Canyon and Desolation-
Gray Canyon), and representative sampling in reaches
downstream of each spawning area is needed to provide an
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