8162

• UCREFRP Catalog Number: 8162
• Author: Osmundson, D. B., R. J. Ryel, M. E. Tucker, B. D. Burdick, W. R. Elmblad and T. E. Chart.
• Title: Dispersal Patterns of Subadult and Adult Colorado Squawfish in the Upper Colorado River.
• USFW Year: 1998.
• USFW - Doc Type: \
• Copyright Material: YES

DISPERSAL PATTERNS OF COLORADO SQUAWFISH
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UTAH i COLORADO
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949
FIGURE 5.-Movement of Colorado squawfish PIT-tagged in the lower reach of the Colorado River. Arrow origins
represent capture location; arrow points represent location of next capture. Consecutive captures were at least 1 year
apart; only movements greater than 10 km are shown.
TABLE 2.-Total lengths of Colorado squawfish before
and after movement from the lower reach to the upper
reach of the upper Colorado River. Only those fish moving
between reaches based on capture-recapture in consecu-
tive years are included; Rkm = river kilometer location.
Lower reach capture Upper reach capture
Fish Length Length
number Year Rkm (mm) Year Rkm (mm)
129 92 81.5
131 94 96.2
186 92 98.9
238 93 58.2
323 93 26.5
C-1 94 97.6
I GU = Gunnison River
438 93 175.2 478
535 95 132.0 580
421 93 154.3 449
523 94 147.1 539
456 94 GU-l.Ia 466
555 95 147.5 577
in 1994, 5 of 16 (31 %) occurred in the upper reach;
in 1995, 5 of 12 (42%) occurred in the upper reach.
It was difficult to ascertain a minimum size for
Colorado squawfish moving from the lower to the
upper reach because recaptures were often 2 years
or more apart. Only six lower-to-upper-reach re-
captures were I year apart. The smallest of these
fish was between 421 and 449 mm when it moved;
the largest was between 555 and 577 mm (Table
2). For fish with greater recapture intervals, the
largest fish was between 570 and 628 mm when
it moved to the upper reach sometime during a
2.5-year period.
Distance moved between captures was inversely