7834

• UCREFRP Catalog Number: 7834
• Author: Burdick, B. D. a. R. B. B.
• Title: Experimental Stocking Of Adult Razorback Sucker In The Upper Colorado And Gunnison Rivers.
• USFW Year: 1997.
• USFW - Doc Type: \
• Copyright Material: NO

1994 UPPER COLORADO RIVER RZ RADIOTELEMETRY
DISPLACEMENT
.010
.-..030
_ .050
.070
.090
.110
p .150
%.W.190
} .211
.241
Z
W
W
GC
LL
O
0
Q
cc
UPSTREAM
DOWNSTREAM
n=20
April-August
.260
.300
.320
.340
.360
.420
.541
.580
.620
.720
.820
30 25 20 15 10 5 0 10 20 30 40 50 60
RIVER MILES
Figure 3. Total maximum upstream and downstream displacement (from
release point: '0' on the X-axis) for 20 radiotagged adult
razorback sucker monitored between March and September 1994
and March and November 1995 in the Upper Colorado River,
Colorado. Note: the upstream scale is one-half that of the
downstream scale.
eight of these were from two fish released 13 September 1995. The five other
radio contacts were from one fish (.683 Mhz) stocked in 1994.
As with razorback sucker released in the Upper Colorado River, fish either
remained at the stocking site or dispersed downstream. Throughout the study,
fish collectively moved a total of 397.3 river miles, most of which was
predominantly downstream (357 miles; Figures 4 and 5). The mean maximum
displacement for the 23 fish was nine times greater downstream than upstream
(14.3 versus 1.6 miles; Figure 6). Six fish exhibited both up- and downstream
movement sometime during the contact period; only one fish (.502 Mhz) exhibited
greater upstream than downstream movement (13.0 versus 7.9 miles). Fourteen fish
exhibited only downstream movement. Fish .683 Mhz exhibited the greatest
upstream movement. This fish moved 22.6 miles upstream and the last contact was
3.7 miles downstream from where it was stocked. Two razorback sucker (.480 and
.760 Mhz) passed over the Redlands Diversion Dam. Fish .760 Mhz passed over the
11