Pacific Ocean Basin: Norton Sound, Alaska; Puget Sound and Snake River, Washington; Snake River, Idaho; Columbia, John Day, Sprague, Umatilla, Umpqua, Rogue, and Willamette rivers, and Clear, Cow, Milk, and Trout creeks, Oregon; Goose Lake, Oregon/California; San Francisco Bay, Merced,

Trinity, and Tuolumne rivers, Carr, Cottonwood, Coyote, Deer, Mill, Salt, Sespe, and Tracy creeks, California. The population in Clear Lake, California no longer exist. (Ref.89241). Common in Puget Sound, Washington, in 1895 (Ref. 28609). Dwarf, nonanadromous and nonparasitic populations landlocked in Oregon and northern California need further taxonomic study (Ref. 5723). The Goose Lake population is considered threatened and has declined since 1989 (Ref. 81264). Also Ref. 4925, 27547.

Status of threat: vulnerable. Criteria: 1,2 (http://fisc.er.usgs.gov/afs/) (Ref. 81264).