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Bull Trout Trends and Abundance*

(DRAFT)

Mid-Columbia Recovery Unit

North Fork John Day River Core AreaMiddle Fork John Day River Core AreaUpper Mainstem John Day River Core AreaWalla Wall River Core AreaUmatilla River Core AreaImnaha River Core AreaSheep Creek Core AreaGranite Creek Core AreaGrande Ronde River Core AreaLittle Minam River Core AreaPine/Indian/Wildhorse Core AreaPowder River Core AreaYakima River Core AreaWenatchee River Core AreaEntiat River Core AreaMethow River Core AreaTucannon River Core AreaAsotin Core AreaNorth Fork Clearwater River Core AreaFish Lake (North Fork Clearwater River) Core AreaLochsa River Core AreaFish Lake (Lochsa River) Core AreaSelway Core AreaSouth Fork Clearwater Core AreaLower and Middle Fork Clearwater River Core Area Abundance: 5,100 - 16,400
Trend: Declining

Historic and current activities have led to conditions that are limiting bull trout abundance and productivity in the Mid-Columbia River Recovery Unit. Activities such as construction of impassable dams/culverts/diversions, land-use management, road construction/maintenance, and past fisheries management actions have affected the quality and quantity of riparian habitat and aquatic conditions.

Throughout the recovery unit, numerous dams/culverts/diversions prevent bull trout passage, fragment habitat and population, and degrade water quality/quantity.

Historic and present land-use practices (i.e., forestry, grazing, agriculture, and mining) have degraded riparian and aquatic resources. Habitat degradation and impaired water quality/quantity are limiting bull trout abundance and productivity.

Construction and maintenance of road networks for forestry activities and general transportation have degraded habitat and water quality/quantity. Impacts associated with the transportation network in the Mid-Columbia River Recovery Unit include increased sediment loading, altered runoff patterns, restriction of normal stream channel movements and bank stabilization, and migration barriers.

Effects from past fishery management practices (non-native brook trout releases) continue to limit bull trout abundance and productivity. Brook trout present an on-going threat to bull trout through hybridization and possible competition for resources, as well as potential predation.

*The abundance and trend estimates represents summations of the information provided in the USFWS 5-Year Review. For a comprehensive review of the estimated abundance and trends, please refer to U.S. Fish and Wildlife Service. 2008. Bull Trout (Salvelinus confluentus) 5-Year Review: Summary and Evaluation. U.S. Fish and Wildlife Service. Portland, OR. 55 pp.

For a comprehensive review of the limiting factors affecting bull trout in this recovery unit, please refer to:
http://www.fws.gov/pacific/bulltrout/RP/Chapter_9%20John%20Day.pdf
http://www.fws.gov/pacific/bulltrout/RP/Chapter_10%20Umatilla.pdf
http://www.fws.gov/pacific/bulltrout/RP/Chapter_11%20Grande%20Ronde.pdf
http://www.fws.gov/pacific/bulltrout/RP/Chapter_12%20Imnaha.pdf
http://www.fws.gov/pacific/bulltrout/RP/Chapter_13%20Hells%20Canyon.pdf
http://www.fws.gov/pacific/bulltrout/RP/Chapter_21%20Middle%20Columbia.pdf
http://www.fws.gov/pacific/bulltrout/RP/Chapter_22%20Upper%20Columbia.pdf
http://www.fws.gov/pacific/bulltrout/RP/Chapter_16%20Clearwater.pdf

Adapted from:
U.S. Fish and Wildlife Service. 2002. Chapter 9, John Day River Recovery Unit, Oregon. 82 p. In: U.S. Fish and Wildlife Service, Bull Trout (Salvelinus confluentus) Draft Recovery Plan, Portland, OR.

U.S. Fish and Wildlife Service. 2002. Chapter 10, Umatilla-Walla Walla Recovery Unit, Oregon and Washington. 153 p. In: U.S. Fish and Wildlife Service. Bull Trout (Salvelinus confluentus) Draft Recovery Plan. Portland, OR.

U.S. Fish and Wildlife Service. 2002. Chapter 11, Grande Ronde River Recovery Unit, Oregon and Washington. 95 p. In: U.S. Fish and Wildlife Service. Bull Trout (Salvelinus confluentus) Draft Recovery Plan. Portland, OR.

U.S. Fish and Wildlife Service. 2002. Chapter 12, Imnaha-Snake Rivers Recovery Unit, Oregon. 86 p. In: U.S. Fish and Wildlife Service. Bull Trout (Salvelinus confluentus) Draft Recovery Plan. Portland, OR.

U.S. Fish and Wildlife Service. 2002. Chapter 13, Hells Canyon Complex Recovery Unit, Oregon and Idaho. 81 p. In: U.S. Fish and Wildlife Service. Bull Trout (Salvelinus confluentus) Draft Recovery Plan. Portland, OR.

U.S. Fish and Wildlife Service. 2002. Chapter 21, Middle Columbia Recovery Unit, Washington. 86p. In: U.S. Fish and Wildlife Service. Bull Trout (Salvelinus confluentus) Draft Recovery Plan. Portland, OR.

U.S. Fish and Wildlife Service. 2002. Chapter 22, Upper Columbia Recovery Unit, Washington. 113 p. In: U.S. Fish and Wildlife Service. Bull Trout (Salvelinus confluentus) Draft Recovery Plan. Portland, OR.

U.S. Fish and Wildlife Service. 2002. Chapter 16, Clearwater River Recovery Unit, Idaho. 196 p. In: U.S. Fish and Wildlife Service. Bull Trout (Salvelinus confluentus) Draft Recovery Plan. Portland, OR.