7106

• UCREFRP Catalog Number: 7106
• Author: Ferriole, S.
• Title: Wildlife Resource Information System
• USFW Year: 1987.
• USFW - Doc Type: Colorado Squawfish Mapping Criteria for the Colorado, Dolores, Gunnison, Green, White, and Yampa Rivers.
• Copyright Material: NO

White River, upper Green River, and Colorado River between Grand
` Junction and Moab, UT). Juveniles move up tributary river s_ and
"establish residency" just prior to adulthood (Wick et al. 1983).
This kind of movement appears to be responsible for species
recruitment in the upper Yampa River (Wick et al. 1986). -Some
adults appear to have a fidelity to a specific river reach since
individual fish have been recaptured in the same area over a period
of years (Wick et al. 1985).
_ Adult Colorado squawfish habitat use varies with season, flow,
and availability (Holden 1978, Wick et al. 1983, Tyus and McAda
1984). Adults are mostly found in shoreline habitats but other
areas including eddies, pools, runs, backwaters are used, depending
on~river and season (Miller et al. 1983c). Adults leave main
channel areas during peak runoff and move to backwaters, flooded
tributaries and diked side channels where water is slower and
warmer. During high discharge, cold water years, use of such areas
may be important for triggering pre-spawning gonadal development,
especially in upper distrib utional reaches like the Yampa River
(Wick et al. 1983). After peak runoff, adults are associated with
run-riffle habitats where spawning may occur. Adults remain in
relatively small areas from late summer until late spring (Wick et
al. 1986}. Perhaps they move to deep pools in fall (Wick et al.
1983}, and may remain inactive in pools until springtime stimulates
their dispersal (Valdez et al. 1982b).
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