Bull Trout Restoration 2010-2013

bull trout restoration 2013
Bull Trout restoration efforts for 2010-2013.


Restoring Lower Sun Creek (2010 – 2013)

    • Over 7 km of suitable Bull Trout habitat in Sun Pass State Forest occupied by Brook Trout and Brown Trout
  • Partnerships:
    • Restoration project is a collaborative effort among National Park Service, Oregon Dept of Fish and Wildlife, Oregon Dept of Forestry, US Fish & Wildlife Service, and private landowners.
  • Objectives:
    • Restore native fish community to lower Sun Creek and allow passage of native migratory fish between Sun Creek and the Wood River.
  • Methods:
    • Install new exclusion barriers equipped with passage facility as far downstream as possible on Sun Pass State Forest.
    • Characterize nonnative fish community composition, density and biomass prior to removal efforts.
    • Treat with antimycin-A to eradicate nonnative fish between lower NPS barrier and new Oregon Dept of Forestry barrier (7.3 km or 4.5 hours flow time).
    • Reconnect lower Sun Creek channel with Wood River and screen irrigation diversions to promote recovery of migratory Bull Trout and/or colonization by Redband Trout.
  • Results - Pre-Treatment Fish Community and Comparison of Abundance Estimates
    • Brook Trout ranged 29 mm - 288 mm in 2008; 26 mm to 237 mm in 2012
    • Evidence of at least five or six size/age classes of Brook Trout
    • Brook Trout density in electrofishing segments ranged 0.2 fish/m to 1.8 fish/m channel length
    • Total Brook Trout biomass in Lower Sun Creek reach approximately 158 kg (4-5 g/m2), comparable to values for other western streams
  • Volunteer labor for pre-treatment electrofishing: NPS, Oregon Dept of Fish and Wildlife, US Forest Service, Bureau of Land Management, US Fish & Wildlife Service, US Geological Service, Oregon Institute of Technology, Southern Oregon University, Trout Unlimited
  • Removal electrofishing estimates:
    • 2008: N = 5850 Brook Trout (95% C.I. 5069 to 6631), mean density = 0.80 fish/m
    • 2012: N = 4332 Brook Trout (95% C.I. 3385 to 5277), mean density = 0.59 fish/m
  • Mark-Recapture Estimate
    • Marked and released 1002 Brook Trout >65mm FL with caudal clip
    • Recovered 220 marked and 1382 unmarked carcasses >65 mm
    • in chemical treatment
    • N = 7296 (95% C.I. 6571 to 8162)
    • Total Brook Trout biomass approximately 158 kg (4-5 g/m2)
  • Confirmed Bull Trout in Lower Sun Creek
    • Live Bull Trout collected as far downstream as distributary channels (n = 8)
    • Bull Trout mortalities collected during chemical treatment as far downstream as Oregon Dept of Forestry/RR Ranch boundary (n = 22)
    • Additional PIT tagged Bull Trout known to have passed into or through reach (n = 6)
  • Funding and Partners
    • National Park Service
    • Oregon Dept of Fish and Wildlife - Klamath Lake District
    • Oregon Dept of Fish and Wildlife Restoration and Enhancement Board
    • Oregon Department of Forestry
    • US Fish and Wildlife Service
    • National Fish and Wildlife Foundation
bull trout warning
Signage warning of Bull Trout restrictions for fishing.


Last updated: March 17, 2016

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