Bull Trout distribution

Description of the bull trout distribution in the pacific northwest.

Historic bull trout distributions in the pacific northwest.

Western Native Trout Campaign

  • The bull trout is a char most closely related to white-spotted char of northeast Asia
  • Historic range from northern California (McCloud River) and Nevada to northern Canada, now extirpated from California
  • One of the most restricted temperature tolerances of any North American salmonid: optimal growth at ~13°C, decline in feeding ≥16°C
  • Exhibit diverse life histories, including resident, potamodromous, and anadromous forms
  • Known for piscivory at large sizes
  • Once maligned as “trash fish” subject of eradication efforts during early 20th century
Maps of the distribution of Bull Trout.

Upper Klamath Basin Bull Trout distributions.


  • Bull Trout once widely distributed in Upper Klamath Basin at least as far downstream as Keno.
  • At least 40% of historical Bull Trout populations in the basin have experienced recent extirpation (Buchanan et al. 1997).
  • Bull Trout now limited to discrete isolated headwater populations.
  • Listed as threatened under ESA in Klamath in 1998, prior to range-wide listing in 1999
  • Basin-wide recovery goals include expanding populations downstream.
  • In 1989 Bull Trout in Sun Creek were restricted in distribution to 1.9 km and numbered approximately 150 individuals.
  • Threats included nonnative Brook Trout (S. fontinalis) and lack of habitat connectivity due to irrigation of private land.

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