Hatchery propagation did not reduce natural steelhead productivity relative to habitat conditions and predation in a mid-Columbia River subbasin

For over 150 years, hatchery-origin anadromous salmon and trout have been reared released throughout the Pacific Northwest to mitigate for lost habitat sustain harvest opportunity. Some studies demonstrate that introgression of hatchery naturally produced fish may constrain conservation efforts through maladaptive genetic processes. However, empirical demonstrations influence these interactions on population productivity are lacking, making it difficult assess their importance relative other drivers productivity. We estimated effect proportion spawners (pHOS), proportionate natural (PNI), releases adult winter steelhead recruitment in Hood River, Oregon, a 27-year period record. Adult was not associated with pHOS PNI. positively ocean conditions, stream flow, release numbers, while negatively pinniped abundance. Our analysis highlights quantifying programs production environmental factors known affect natural-origin recruitment.