7761

• UCREFRP Catalog Number: 7761
• Author: Ryden, D. W. and F. Pfeifer.
• Title: San Juan River Recovery Implementation Program Annual Research Report.
• USFW Year: 1994.
• USFW - Doc Type: \
• Copyright Material: NO

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11 Percent composition by age class per reach for channel catfish
and common carp, 1991-1993, all sampling trips in a year
combined. Dashed lines indicate juvenile fish, solid lines
indicate adult fish. Circles represent 1991 data, asterisks 1992,
and triangles 1993 . . . . . . . . . . . . . . . . . . . . .. 19

12 Mean total length (TL) in millimeters (mm) for channel catfish
and common carp, 1991-1993, all sampling trips in a year
combined. Line and crosses represent mean TL, asterisks
represent standard deviations, and error bars represent the

range. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

13 Map showing the approximate locations of all Colorado squawfish
collections and sightings, and roundtail chub collections in the
San Juan River, New Mexico, Colorado, and Utah, 1993 . . .. . 23

14 Year-round movements of five radio-tagged Colorado squawfish as
established by 49 radio contacts (from RM 142.0-117.0) from
January 12 to December 2, 1993. Vertical dashed lines indicate
the Mixer area (RM 133.4-129.8) and the Mancos River (RM 122.6).
Horizontal dashed lines indicate the presumed spawning period.
Due to the large difference in RM, the movements of a sixth radio-
tagged Colorado squawfish (910) captured in 1993 are shown on

Figure 15. . . . . . . . . . . . . . . . . . . . . . . . . .. 26

15 Riverwide movements of twelve radio-tagged Colorado squawfish,
1991-1993. Dashed lines indicate the borders of Reach 3 . .. 27

16 Habitat types recorded for radiotelemetered Colorado squawfish in
the San Juan River, New Mexico, 1991-1993. Numbers in parentheses
are values obtained in a similar study done in the Green and Yampa
Rivers in 1984, n = total number of observations during this study,

1991-1993. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

17 Year-round movements of eleven radio-tagged Colorado squawfish as
established by 150 radio contacts from June 1991 to December 1993.
Although the entire river was searched, 11 of 12 radio-tagged
Colorado squawfish were always contacted between RM 142 and 117.
Vertical dashed lines indicate the Mixer area (RM 133.4-129.8) and
the Mancos River (RM 122.6). Horizontal dashed lines indicate the
presumed spawning period for each year . . . . . . . . . . . . . . 33

18 Number of fish (in thousands) weighed and measured by reach and
by trip for the four most abundant species, 1991-1993. Numbers
above the columns indicate percentage of the total number of
characterized fish per species for a given sampling trip
represented by that age class. . . . . . . . . . . . . . . . . . . 65

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