Colorado pikeminnow (=squawfish)

Ptychocheilus lucius

SPECIES CODE: E006 V01

STATUS:

Listed Endangered (32 FR 4001, March 11, 1967) in the entire, except Salt and Verde R. drainages, AZ, with Critical Habitat (59 FR 13374 13400, March 21, 1993).

SPECIES DESCRIPTION:

The Colorado pikeminnow is a member of the Cyprinidae family.

REPRODUCTION AND DEVELOPMENT:

RANGE AND POPULATION LEVEL:

The Colorado squawfish is endemic to the Colorado River basin and much of its main tributaries. The species has been collected in

1. Arizona: Gila River and its tributaries, the San Pedro, Salt, and Verde Rivers; the Colorado River mainstem from the United States-Mexico border

to the Utah-Arizona State line and the lower most Little Colorado River (Minckley 1973, 1985).

2. California: Colorado River mainstem from the United States-Mexico border to the Nevada State line and the Salton Sea, which was sporadically filled

with water from the Colorado River (Minckley 1973, 1985; Moyle 1976).

3. Colorado: Colorado River and lower reaches of the Gunnison, White, Yampa, Little Snake, Dolores, San Juan, Uncompahgre, and Animas Rivers (Jordan

1891; Ellis 1914; Beckman 1952; Lemons 1954; Johnson 1976; Valdez et al. 1982a), and Plateau Creek, a tributary of the Dolores River (Bob Burdick,

U.S. Fish and Wildlife Service, pers. comm. 1990.).

4. Nevada: Colorado River mainstem (La Rivers 1962).

5. New Mexico: San Juan and Animas Rivers (Koster 1957, 1960; Platania 1990).

6. Utah: Colorado, Green, Duchesne, San Juan, White, and Dolores Rivers, and probably numerous smaller streams (Ellis 1914; Holden 1973; Seethaler

1978).

7. Wyoming: Green River mainstem (Baxter and Simon 1970; Bosley 1960; Johnson and Oberholtzer 1987) and Little Snake River (Marsh et al. 1991).

8. Mexico: Mainstem Colorado River and its tributaries and sloughs from the United States-Mexico border to the Gulf of California (Sonora and Baja

California del Norte) (Follett 1961; Minckley 1979).

Natural Colorado squawfish populations survive only in the Upper Basin, where their numbers are relatively high only in the Green River Basin of Utah and Colorado (compared with other rivers in the Upper Basin)(Tyus 1991).

HABITAT:

PAST THREATS:

The construction of dams and water diversion has severely fragmented the species’ historical range.

CURRENT THREATS:

CONSERVATION MEASURES:

LITERATURE CITED:

U.S. Fish and Wildlife Service. 1990. Colorado Squawfish Recovery Plan. U.S. Fish and Wildlife Service, Denver, Colorado. 56pp.