WSP07697

• File Number: 8240.200.10.B
• Description: UCRBRIP - Riverine Fish Flow Investigations
• Basin: Colorado Mainstem
• Date: 7/1/2001
• Author: CDOW
• Title: Riverine Fish Flow Investigations 2001
• Water Supply Pro - Doc Type: Publication

habitats. Backwaters were sampled more intensively in 2000 than in 1999 with sunfish

removed in 2000, but not in 1999. As was the case in 1999, non-native cyprinds (NNC; red

shiner, sand shiner and fathead minnows) were very abundant in backwater habitats, and only

relatively few were sampled so NNC composition is much higher than reported here. Refer to

seining studies by Valdez (1999) and Bestgen et al (1999) for data on backwater species

composition.

Table 5. Species composition for fish <15 em in the 15-MlLE Reach Colorado River at the
Corn Lake station (October 1999, and August 2000) and Clifton (August 2000).

Corn Lake Corn Lake Clifton Clifton
Species 1999 2000 1999 2000
Flannelmouth Sucker 5.8% 5.6% 5.3% 6.3%
Bluehead Sucker 0.5% 1.4% 0.0% 6.2%
Roundtail Chub 22.3% 2.3% 3.9% 3.7%
Colo. Pikeminnow
White sucker 4.6% 4.9% 2.4%
White X Flannelmouth
White X Bluehead
Channel Catfish
Carp 3.6% 3.2% 2.6% 6.2%
Smallmouth Bass 0.8% 0.4%
Largemouth bass 5.8% 11.5% 0.0% 10.6%
Green Sunfish 7.4% 32.0% 2.6% 11.8%
Brown trout 0.1% 0.1% 0.1%
Rainbow trout
Black Bullhead 0.8% 0.6%
Razorback Sucker 4.2%
Speckled Dace 2.8% 19.8% 21.1% 38.8%
Mottled Sculpin 0.5% 0.5% 1.3%
Red Shiner 20.7% 6.8% 43.4% 6.2%
Sand Shiner 21.5% 1.3% 5.3% 3.3%
Fathead Minnow 3.5% 3.6% 14.5% 1.7%
Bluegill 0.1% 0.5% 1.3% 0.3%
Mosquitofish 1.0% 0.4%
Mountain whitefish 0.1% 0.4%
Sample size 781 1151 87 780

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