2021 Columbia River Steelhead Crisis (rev. 9-15-21)

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2021 Columbia River Steelhead Crisis (rev. 9-15-21) Current Summer Steelhead returning to the Columbia River above Bonneville Dam1: April 1 thru September 14 Ø 54,313 total hatchery and wild steelhead (H + W) have passed Bonneville Dam o The pre-season estimate was 96,800 steelhead, half of which (48,400) were expected to pass Bonneville by August 20 – 2021 passage on August 20 was half of expected passage of the second lowest steelhead run since 1975. The updated run is now 60,200 total hatchery and wild steelhead. Ø 21,134 total wild, unclipped steelhead have passed Bonneville Dam • •

The current 10-year average steelhead passage is 168,761 combined hatchery & wild steelhead The current 10-year average wild fish passage is 64,881 wild summer steelhead.

Comparing current passage with the Current Ten-year Average (CTYA) (2011-2020): v The current 2021 return of combined wild and hatchery steelhead is 32.2% of the CTYA. v The current 2021 return of wild (or unclipped) summer steelhead is 32.6% of the CTYA. Hatchery fish outnumber wild fish 33,179 to 21,134 fish (some adipose-intact fish are hatchery-origin). What we have lost: Avoid the declining baseline syndrome, compare current run with a longer data set The “best” 10-year average for H+W steelhead since 1984 was between 2001-2010 (355,508 steelhead). The “best” 10-year average for wild steelhead since 1984 was from 2001-2010 (107,447 wild steelhead) Ø The 2021 combined run is 15.3% of the best 10-year average (321,618 H+W fish during 2001-2010) Ø The 2021 wild run is 20% of the best 10-year average (107,447 wild fish during 2001-2010) Current Summer Steelhead returning to the Columbia River above Lower Granite Dam2: June 1 thru Sept. 14 Ø 4,754 combined hatchery and wild steelhead have passed Lower Granite Dam Ø 1,924 total wild steelhead have passed Lower Granite Dam The current 10-year average steelhead passage is 14,675 combined hatchery & wild steelhead. The current 10-year average unclipped/wild fish passage is 5,499 wild summer steelhead. Comparing current Steelhead passage with the Current Ten-year Average at LGD (CTYA) (2011-2020): v The current 2021 return of combined wild and hatchery steelhead is 32.4% of the CTYA. v The current 2021 return of wild (or unclipped) summer steelhead is 35% of the CTYA. What we have lost: Avoid the declining baseline syndrome, compare current run with a longer data set The “best” 10-year average for H+W steelhead since 1984 was between 2001-2010 (33,581 steelhead). The “best” 10-year average for wild steelhead since 1984 was from 2001-2010 (9,942 wild steelhead) Ø The 2021 combined run is 14.2% of the best 10-year average (33,581 H+W fish during 2001-2010) Ø The 2021 wild run is 19.4% of the best 10-year average (9,942 wild fish during 2001-2010)

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Numeric Data is from the UW Columbia River DART website: http://www.cbr.washington.edu/dart/query/adult_graph_text

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Numeric Data is from the UW Columbia River DART website: http://www.cbr.washington.edu/dart/query/adult_graph_text


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