WSP01392

• File Number: 8240.200.10.B
• Description: UCRBRIP - Riverine Fish Flow Investigations
• Basin: Colorado Mainstem
• Date: 6/1/2000
• Author: CDOW
• Title: Riverine Fish Flow Investigations 2000
• Water Supply Pro - Doc Type: Publication

I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I

Table 2: Species composition for fish >15 cm at the Duffy station in 1998 and 1999.
Column 3 is for the study area with habitat composition data.

I.TOTAL 2. ABOVE 3. SURVEY 4. STUDY 5. BEND
Columns STUDY STUDY TO TO
2,3,4&5 AREA AREA BEND TAKE our
Species 1998 ELECTROFlSHING
Flannelmouth Sucker 53% 2.7% 7.5% 61%
Bluehead Sucker 4.4% 4.4% 4.1% 4.6%
Roundtail Chub 3.3% 2.1% 6.6% 2.7%
Colo. Pikcminnow 1.5% 1.7% 0.0% 2.0%
While sucker 34.9% 49.1% 34.6% 25.7%
While X Flannelmouth 28.1% 22.6% 27.4% 31.9%
White X Bluehead 60% 4.0% 12.9% 4.6%
Channel Catfish 3.0% 0.9% 0.9% 5.1%
Carp 2.7% O.9o,~ 0.0% 4.8%
Smallmoulh Bass 8.2% 7.4%) 4.1% 10.3%
Northern Pike 2.8% 4.0~~ 1.9% 2.3%
While Crappie 0.1% 0.2%.
While S. + Crosses 68.9% 75.7% 74.8% 62.2%
Sample size 1654 527 318 809
Recaptures 270 87 71 112
Species 1999 ELECTROFISHING
Flannelmoulh Sucker 5.1% 5.6% 2.4c}~ 2.7% 7.6%
Bluehead Sucker 5.6% 3.3% 4.3% 4.8% 8.2%
Roundtail Chub 2.9% 3.5% 2.4% 3.3% 2.7%
Colo. Pikeminnow 0.6% 0.0% 1.0% 0.3% 0.9%
White sucker 33.4% 33.7% 40.9% 37.5% 26.3%
While X Flannelmouth 328% 41.6% 30.1% 28.5% 30.9%
While X Bluehead 5.9% 2.5% 5.7o,~ 13.5% 4.8%
Channel Catfish 4.0% 1.0% 4.1~}o 3.0% 6.\%
Carp 1.1% 0.2% 0.2(% 0.6% 2.6%
Smallmouth Bass 6.3% 7.5% 6.3% 3.9% 6.5%
Northern Pike 2.3% 0.8% 2.8% 1.8% 3.1%
While Crappie 0.1% 0.2% 0.0% 0.0% 0.1%
White S. + Crosses 72.0% 77.8% 76.6% 79.6% 62.1 %
Sample size 2092 483 509 333 767
Recaptures 440 \30 107 6\ 142

section below the study area, and 32% above the study area (Table 3). The weighted mean for

all sites combined was 43% (Table 3). The next most common fish was bluehead sucker. The

study area had the highest percent of blue head sucker, almost as common as flannel mouth,

31