8160

• UCREFRP Catalog Number: 8160
• Author: Trammell, M. and T. Chart.
• Title: Aspinall Studies
• USFW Year: 1999.
• USFW - Doc Type: Evaluation of Nursery Habitat Availability and Colorado Pikeminnow Young of Year Habitat Use, in the Colorado River, Utah, 1992-1996\
• Copyright Material: NO

Table 15. Multinomial analysis for Colorado pikeminnow use of habitat types, based on the
percent each habitat type comprises of the total sampled habitat area, and the number
of each type containing pikeminnow. Colorado River nursery habitat, Upper and ~
Lower sections, 1992 - 1996.
Upper section, Total, all trips
Habitat type Obs. % of
hab type Obs. number of
habs with CPM Expected number
of habs with CPM Chi-square
factor
FT 11.3 4 8.9 2.72
HS 9.5 14 7.5 5.61
MS 49.5 38 39.1 .03
SC 28.8 23 22.8 0.0
SE 0.8 0 .66 0.6
Total 100 79 78.96 p = .06 9.02
Lower section, Total, all trips
Habitat type Obs. % of
hab type Obs. number of
habs with CPM Expected number
of habs with CPM Chi-square
factor
FT 8.0 8 9.8 .35
HS 3.6 5 4.5 .06
MS 37.4 54 46.0 1.38
SC 48.5 53 59.8 .75
SE 2.4 3 2.95 0
Total 100 123 123.05 p = .64 2.53

a
The aspects of depth and geomorphology that characterize the preferred habitat of YOY
pikeminnow maybe combined into one feature; that of persistence. The persistence of individual
habitats was monitored over time using the aerial video prints matched against field observations.
Habitats associated with migrating sandwaves tend to be transient within a season. The overall ,
quantity of shallow habitats fluctuates while the actual locations of the habitats continuously
change. However, deep backwater habitats associated with secondary channels tend to be more
permanent than those associated with migrating sandwaves, and often persist from the end of the
spring runoffthrough late fall and into the following spring, or even for several years. These
"quality" permanent habitats are likely to be instrumental in overwinter survival of pikeminnow, .
but they must share this superior habitat with competitive species (Beyers et al. 1994; Ruppert et
al. 1993; Muth and Snyder 1995).
20