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<br />~ JL i;<rW~ H- ~...~ ]t. -"..."...-...,~,"-........ -'""'~~JJ! lJ 'J(\(~'iIlf<;: "UI'~.~"'~ f'1~"'; ~ ~ "lr'" TJr<!'~ li..1 ' ~:' \f?~rnrl~~~:nVl.1I~~
<br />
<br />IN. 0' utala
<br />
<br />ad terrestrial
<br />., small crus-
<br />tages of game
<br />jI8pOds, ostra-
<br />
<br />DIe lautorie.
<br />
<br />
<br />t five inches.
<br />IIree and one-
<br />D the males.
<br />
<br />Importance
<br />In fonner times when this large fish was more abundant it pro-
<br />vided a valuable source of food for the Indians and early settlers,
<br />particularly in those parts of the Colorado River system where white-
<br />fish and trout did not occur. It is important now as a zoological
<br />rarity, deserving of preservation.
<br />
<br />i I
<br />
<br />found vary
<br />iIoes in rivers
<br />.. sloughs and
<br />mer tempera-
<br />_n taken in
<br />~ may be very
<br />:rdel, rubble,
<br />if to swift; the
<br />i. Jess than one
<br />is common to
<br />ia often found
<br />
<br />Range
<br />The Colorado squawfish is native only to the Colorado River
<br />and its major tributaries, from Mexico to Wyoming. It has been
<br />collected at relatively few places in Utah: Green River in and near
<br />Hideout Canyon (near the Wyoming boundary) and in Flaming
<br />Gorge, at Jensen, the town of Green River and from several
<br />adjacent localities in Daggett and Uintah Counties. Specimens have
<br />also been taken near the mouth of Dolores River, about 20 mile~
<br />northeast of Moab, from the Colorado River at Moab, in Trachyte
<br />Creek near Hite (Smith, 1959: 197), and from San Juan River at
<br />.Mexican Hat (three young taken August 21, 1960, by R. R., G. H.,
<br />and F. L. Miller).
<br />
<br />"
<br />I ~
<br />
<br />rado
<br />
<br />Description
<br />
<br />The elongate body, the large, nearly horizontal mouth, the long
<br />cone-shaped head, and the very narrow and elongate lower limb of
<br />the pharyngeal arch readily separate this minnow from its close
<br />relative, the Colorado chub (Gila robusta). As in the roundtail,
<br />(Gila r. robusta) the number of dorsal and anal fin-rays is almost
<br />'invariably 9 and the dorsal fin originates behind the insertion of the
<br />pelvic fins; likewise the scales are small, about 80 to 95 in the lateral
<br />line, and frequently are missing or very deeply embedded on the
<br />breast and belly. The pharyngeal teeth are arranged in two rows,
<br />2,5-4,2, and are frail, elongate, and hooked at the tips. The length
<br />of the lower limb of the pharyngeal arch is much greater than the
<br />whole width of the upper part of the arch (Miller, 1955a, pI. 4). The
<br />upper' jaw in adults reaches to about the middle of the pupil, and
<br />the eye is small. The coloration is bright olive green, darker above,
<br />the lower sides becoming somewhat yellowish and the abdomen
<br />whitish; the young have a dark, wedge-shaped spot at the base of
<br />the caudal fin.
<br />
<br />Life History
<br />
<br />The Colorado squawfish is a carnivorous predator, as indicated
<br />by its well-streamlined body, large size, largemouth and faptorial
<br />
<br />78
<br />
<br />I
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