9408

• UCREFRP Catalog Number: 9408
• Author: Foster, D. K. and G. Mueller.
• Title: Movement Patterns, Behavior, and Habitat Use of Razorback Sucker Stocked Into the Green River at Canyonlands National Park, Utah.
• USFW Year: 1999.
• USFW - Doc Type: Open-File Report 99-107,
• Copyright Material: NO

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Powell adjacent to the mouth of Gypsum Canyon some 85 km downstream.
Fish SE reached the confluence in no longer than 7.8 days and, as previously mentioned,
swam up the Colorado River at least 72 km. Between 19 and 24 days after its release, SE
began to move downstream and was last contacted 4.8 km above the Green River
confluence.
Razorback sucker 15E was the only fish observed to move upstream in the Green River
during the course of the 58-day study. Initially, 15E moved downstream to Green River
RK 29.1 by day 11.4. During the next 9 days, 15E moved 2.5 km upstream. During
days 20 to 47, razorback 15E then moved upstream again and was last contacted day 49
!, at Green River RK 41.4-12 km below the release point.
Razorback 2C reached the confluence and traveled at least 24.9 km up the Colorado River
during the initial 14 days. During the next 13 days, 2C moved 30.5 km downstream to
6 km below the Green River confluence. This position was ~0.9 km above the first
Cataract Canyon rapid. Later this same day, at 1733 (day 27.9), 2C had moved into
Cataract Canyon rapids and was in the large, swift, eddy pool circulating below rapid #2
(Colorado River km 340.2, confluence = RK 348.5). By the following afternoon at
1622, fish 2C had completed its journey through Cataract Canyon rapids and was located
~0.5 km above Imperial Canyon (Colorado River RK 322.3). Fish 2C was able to move
through the ~21 km of rapids in 1.05 days. By day 56, fish 2C's last known position was
just inside the mouth of Clearwater Canyon in Lake Powell (Colorado River RK 308.2).
By day 14, razorback 7C had departed the Green River and swam 10.8 km up the
Colorado River. During the next 7 days, 7C moved downstream and to the mixing zone
of the Green and Colorado River confluence. From this time until day 58, razorback 7C
positioned itself at Colorado River RK 345.2 and moved about within a 200-m section of
river. This razorback sucker was observed to still be mobile b
its periodicall
movin
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out from the deep channel (faint tag signal) and swimming along the shoreline (strong tag
signal).
The remaining razorback suckers were either lost from contact early on, or moved
downstream to the Colorado River and positioned themselves between the confluence and
the head of Cataract Canyon Rapids (a reach of ~7 km), or they continued downstream
and entered Lake Powell where contact was generally lost. Razorback suckers 3E, 10E,
1 C, and 9C were all located only once or twice. These four fish were moving
downstream and it is unknown whether ,they later entered Lake Powell, or remained in the
Green or Colorado Rivers and avoided detection by seeking out the deepest portions of
the river. The radio-tag signals may attenuate to below detection levels when ~9 or more
meters deep. Fish 6E, 8E, 14E, SC, and 11 C rapidly moved downstream and out of the
lower 52 km of the Green River and positioned themselves in the previously mentioned
Colorado River reach above Cataract Canyon rapids and the Green River confluence:
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