7752

• UCREFRP Catalog Number: 7752
• Author: Stanford, J. A.
• Title: Instream Flows to Assist the Recovery of Endangered Fishes of the Upper Colorado River Basin
• USFW Year: 1993.
• USFW - Doc Type: Review and Synthesis of Ecological Information, Issues, Methods and Rationale.
• Copyright Material: NO

, !

50

SQUAWFISH DISTRIBUTION

I-
J:
~
::>
<
o

a:
LU
m
~
::>
z

40 ---.. --.-38------..-~-.--..---..---------.---.--.-. .---..---....-.--.-.---.-

35 IN COLORADO RIVER
(1991-1992)

.10

30

20

.. _'__-"__...___m_._..._..._..._~,.._.,._.......;._,.,_._._..._.___._ .._.._..._....

o
185-171

156-141

126-111

96-81

66-51

36-21

6-0

15-MILE SECTIONS OF RIVER

700

629

SQUAWFISH AVERAGE LENGTH
IN COLORADO RIVER

... -- 587----_ __ '.... __. ........ ..... _ ....._
569 (1991-1992)

300

600

-
E
E 500
-

J:
t-
~
Z 400
LU
..J

200
185-171 156-141

126-111

96-81

66-51

36-21

6-0

t

15-MILE SECTIONS OF RIVER

'15-MILE REACH'

Figure 5. Distribution of squawfish by size and number caught in the Colorado River from the
Green River confluence (mile 0) to the Grand Valley diversion dam at the top of the 15-mile reach
during 1991 - 1992. This relationship, although variable, is remarkably consistent from year to
year; the upstream areas inhabited by larger adults are consistently devoid of YOY squawfish
relative to the river segment below Westwater Canyon and the confluence with the Green River
(mile 111 - 0) (Doug Osmundson, U.S. Fish & Wildlife Service, Grand Junction, CO, unpublished
data).

16