9348

• UCREFRP Catalog Number: 9348
• Author: Crane, H. S.
• Title: Fishery Investigations of the Glen Canyon and Flaming Gorge Impoundment Areas.
• USFW Year: 1959.
• USFW - Doc Type: \
• Copyright Material: NO

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According to Simon (1946), the food of the fathead minnow consists primarily
of slime and ooze and their contained organic substances.
Carp (Cyprinus carpio). Carp were found to occur most frequently in muddy
backwaters but were also collected in some clear tributary streams. They
are reported to occur in the Colorado River, but none were collected in the
course of the survey. Jonez (19510 reports that the most abundant fish in
Lake Mead is the Carp. The groarth rate of Carp in the Glen Canyon area appears
to be slow (Table 3). One of the larger, carp collected during the survey was
9 inches in length and was over /~ years old. Larger individuals were ob-
served, however. In contrast to the restricted growth in the Glen Canyon
area, Jonez (1954) reports that in Lake Mead carp grow an average of 8.5
inches during the first year of life. Stomach samples taken from carp in
the Glen Canyon area contained small amounts of algae and amorphous matter.
The carp was first introduced into Kane County about 1882.. (Popov 1950).
Channel Catfish (Ictalurus punctatus). This was the most abundant species
of fish in the Colorado and San Juan Rivers, specimens being taken by dyna-
mite or hook and line throughout the entire length of Glen Canyon. Catfish
were also found to occur in many of the tributaries. Stomach samples in-
dicate that these fish are omniverous, feeding on a great variety of
plant and animal material (Table 4). Insects, algae, parts of other fish
and various other substances were found in the stomachs. Fish occurred
most commonly in the stomachs of the larger catfish. The following ages
are for 13 channel catfish ranging in stands-rd length from 3.5 to 9.7 inches:
Age Classes III IV V VI VII VIII IX
No. of Fish 2 3 1 3 2 1 1
The majority of the fish collected were characterized by large heads
and small bodies indicating a slow rate of growth. Catfish collected in
the river averaged about 8.9 inches in length. The largest catfish observed
during the survey was a 24 inch fish taken from a backwater at Aztec Creek.
Channel catfish were first introduced into the lower Colorado River about
1892 and into the Green and Colorado Rivers in Wyoming prior to 1930. They
were first introduced into the Colorado River in Utah in 1939 (P©pov 1950)-
Black bullhead (Ictalurus melas). Though not abundant, the bullhead was
found to occur in backwaters and in ponds and quiet areas in some of the
tributaries. The largest number of bullheads were observed in ponds in
Warm Springs Creek.
Southwest Plains Killifish (Fundulus zebrinus). The five specimens of'this
fish collected near the mouth of Warm Creek in August, 1958, comprise the only
record of this species in the state. This fish was originally found in the
Brazo and Pecos drainages of Texas and New Mexico in shallow ponds and
streams (Koster 1957)• According to R. Miller, it was probably introduced
into the Little Colorado River drainage of northern Arizona about 193$•