Editing Steelhead (section)

=== Oregon ===
[[File:Management Units and Population Segments for the MCR Steelhead.png|thumb|Management Units and Population Segments for the MCR Steelhead.]]
Within the state of Oregon there are four different distinct steelhead population segments: Lower Columbia River steelhead, Middle Columbia River steelhead, Oregon Coast steelhead, and Upper Willamette River Steelhead<ref>{{Cite web |last=NOAA Fisheries |date=September 2, 2023 |title=Steelhead |url=https://www.fisheries.noaa.gov/species/steelhead-trout/overview |website=National Ocean and Atmospheric Administration}}</ref> (NOAA). Of these four segments, three are listed as threatened under the Endangered Species Act. The Middle Columbia River (MCR) segment has remained the focus of recent recovery efforts. The MCR segment covers approximately 3,500 square miles of the Columbia Plateau in eastern Oregon and Washington.<ref name=":0">{{Cite web |last=National Ocean and Atmospheric Association |date=January 15, 2013 |title=Endangered and Threatened Species: Designation of a Nonessential Experimental Population for Middle Columbia River Steelhead above the Pelton Round Butte Hydroelectric Project in the Deschutes River Basin, OR. |url=https://www.federalregister.gov/documents/2013/01/15/2013-00700/endangered-and-threatened-species-designation-of-a-nonessential-experimental-population-for-middle |website=National Ocean and Atmospheric Administration}}</ref> Within eastern Oregon, recovery efforts focus on the two main tributaries to the Columbia River: The Deschutes River and the John Day River, although the Umatilla and Walla Walla are also included in recovery plans.<ref name=":1">{{Cite web |last=Oregon Department of Fish and Wildlife |date=September 2019 |title=Conservation and Recovery Plan for Oregon Steelhead Populations in the Middle Columbia River Steelhead Distinct Population Segment: 2010 – 2016 Implementation Progress Report. |url=https://www.dfw.state.or.us/fish/CRP/mid_columbia_river_plan.asp}}</ref> Primary threats to MCR steelhead populations include hydrosystem operations, habitat alteration, and effects of stray naturally spawning hatchery fish.<ref name=":0" /> MCR steelhead were first listed as threatened on March 25, 1999, following the construction of Round Butte Dam at the confluence of the Deschutes and Metolius rivers.<ref name=":0" /> The construction of the dam created reverse currents (currents flowing upstream) in the Metolius Arm of Lake Billy Chinook (a reservoir created by the formation of the dam) confusing anadromous smolts and preventing them from navigating seaward. The construction of Round Butte Dam impeded steelhead access to the Upper Deschutes, Crooked, and Metolius rivers, three major tributaries to the Deschutes within the MCR watershed.<ref name=":0" /> In addition to Round Butte, several other dams restrict fish from their native spawning grounds within the Deschutes watershed including Pelton Dam, Bowman Dam, and Ochoco Dam. The first MCR Distinct Population Segment ESA Recovery Plan was released on November 30, 1999. Between 2010 and 2016 1,715 different entities have implemented 1,559 tributary restoration projects primarily focused on habitat restoration and fish passage improvement.<ref name=":0" /> In a 2016 an action plan implementation progress report stated the population  is "maintained" showing no significant upward or downward trend in the yearly number of returning adults in an experimental small tributary to the Deschutes River.<ref name=":1" /> However, fish counts at Boneville Dam, on the Columbia River below the Deschutes confluence have shown a 10 year (2013–2022) average of 162,988 returning adults, and a four year (2019–2022) average of 97,352, suggesting a recent decline in rates of returning adults.<ref>{{Cite web |last=University of Washington School of Aquatic and Fishery Sciences |date=2020 |title=DART Bonneville "Quick Look" Adult Steelhead Passage with River Environment and Historical Run Timing. |url=https://www.cbr.washington.edu/dart/quick_look/adult_bon_stlhd |website=DART Boneville}}</ref>