9660

• UCREFRP Catalog Number: 9660
• Author: U.S. Fish and Wildlife Service.
• Title: Colorado Squawfish Revised Recovery Plan - Draft.
• USFW Year: 1990.
• USFW - Doc Type: Denver, CO.
• Copyright Material: NO

DRAFT
The Colorado squawfish is an elongated pike-like fish. The mouth is large and
nearly horizontal, with a pharyngeal tooth formula of 2,5-4,2; the long,
slender pharyngeal teeth are adapted for grasping and holding prey. The
dorsal fin has nine rays and originates slightly posterior to the insertion of
the p~lvic fins. The scales are small and embedded on the belly, breast, and
nape,, and number 80-95 in the lateral, line. Adults are strongly countershaded
with ~ dark, olivaceous back; lighter sides; and a white belly. Young usually
have a dark, wedge-shaped spot at the base of the caudal fin.
Histot^ic Distribution
The Colorado squawf ish is endemic to the Colorado River basin. Early records
indicate it was abundant in the mainstem Colorado River, most of its major
tributaries, and in the Colorado River delta in Mexico (Jordan and Evermann
1896) (.Figure 1). Colorado squawfish have been reported at the following
locat'ons:
1. C~lorado: Colorado River and lower reaches of the Gunnison, White, Yampa,
LiLttle Snake, Dolores, San Juan, Uncompahgre, and Animas rivers (Jordan
1891; Ellis 1914; Beckman 1952; Lemons 1954; Johnson 1976; Valdez et al.
1982a).
2. Wyoming: Green River mainstem (Baxter and Simon 1970; Bosley 1960;
J~hnson and Oberholtzer 1987).
3. Utah: Colorado, Green, Duchesne, San Juan, White, and Dolores rivers, and
probably numerous smaller streams (Ellis 1914; Holden 1973; Seethaler
1~~'978) .
4. N~'ew Mexico: San Juan and Animas rivers (Koster 1957, 1960; Platania
1'990).
5. A~izona: Gila River and its tributaries, the San Pedro, Salt, and-Verde
r~Iivers; the Colorado River mainstem from the U.S.-Mexico border to the
Utah-Arizona State line and the lower most_Little Colorado River {Hinckley
11973, 1985) .
i
6. Nlevada: Colorado River mainstem (La Rivers 1962).
7. California: Colorado River mainstem from the U.S.-Mexico border to the
Nevada State line and the Salton Sea, which was sporadically filled with
w'~ater from the Colorado River (Hinckley 1973, 1985; Moyle 1976).
~~
8. M~xico: Mainstem Colorado River and its tributaries and sloughs from the
U.S.-Mexico border to the Gulf of California (Sonora and Baja California
d~,el Norte) (Follett 1961; Hinckley 1979).
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