7953

• UCREFRP Catalog Number: 7953
• Author: Miller, W. H., et al.
• Title: Colorado River Fisheries Investigations, 1979 Progress Report - Draft,.
• USFW Year: 1980.
• USFW - Doc Type: ‎(submitted in partial fulfillment of Contract No. 9-07-40l-1016 with the Water and Power Resources Service)‎,
• Copyright Material: NO

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indicated that the young-of-the-year Colorado squawfish move between
these backwater areas and the main river channel. There is evidence of
a diurnal movement pattern with the largest numbers inhabiting backwaters
around midnight. Of the 54 squawfish captured, marked and released, a
total of 9 were subsequently recaptured. Figure 7 presents the catch of
young squawfish in total numbers per time period.
Humpback chub. - Humpback chub adults were collected in eddies, runs and
shoreline habitats but young chub were collected only in backwaters and
runs.
Water depth, velocity and substrate data acquired during the collection
of humpback chub revealed: (1) young fish were found in water rangiIPg
in depth from 0.75 to 3.5 feet and adults were found in water depths
between 1.5 to 5-fleet; (2) adults chub were collected in water with a
velocity of 0.05 to 0.9 fps and youi IP were collected in water with
velocities up to 1.6 fps; (3) adult hub were collected over a wide
3
range of substrate types and young fish were collected only over sand
and silt.
Other fishes. - During the 1979 sampling season much data were collected
on other fish species. These data are still being entered into the
MANAGE computer system and are as-yet unavailable for this report, We
plan to present these data in the 1980 report.