7823

• UCREFRP Catalog Number: 7823
• Author: Miller, W. H., et al.
• Title: Colorado River Fishery Project, Part II, Final Report, Field Investigations.
• USFW Year: 1982.
• USFW - Doc Type: \
• Copyright Material: NO

Radiotelemetry studies (see Migration and movement section) in the
Green River in 1980 and 1981 and the Yampa River in 1981 (Tyus et al. 40
1981, 1982) clarified some confusion about distribution and abundance
patterns of adult Colorado squawfish. Colorado squawfish are migratory
and apparently seek limited spawning areas. These spawning areas are not
utilized to any great extent other than during the July spawning season
when adults appear relatively common on these sites. We believe this is
an important finding and should be used to interpret collections of
Holden and Stalnaker (1975), Seethaler (1978) and others who noted
unusual distribution patterns of adult Colorado squawfish during the
spawning season.
The distribution and relative abundance of YOY Colorado squawfish
was determined in part by special collections made each fall, 1979 to
1981 (Figures 13, to 15). YOY fish were distributed from the mouth of
Split Mountain Canyon (RM 320, 515 kilometers) to Mineral Bottom (RM 50,
81 kilometers) all 3 years. Newly-spawned fish (n = 32) were also found
in Island Park (RM 325-340, 523-547 kilometers) in 1980 and 1981.
Figure 13
10.0
r
¢
O
7.5
w
a
x
U
a
u
5.0
2.5
0.0
30 5 40 110 60 150 170 190 210 230 250 270 290 310 330 M
RIVER MILES 1
?A B I C D I E I F I G I H
STRATA
Catch per unit effort of young-of-the year Colorado squawfish
special investigations from backwaters, Green River, 1979.
One unit of effort equals lom2 sampled with seines.
E
0
0
34