Jeffrey A. Falke Jimmy Fox Robert Henszey Katherine Lininger Charles N. Cathcart 2025 <p><span>Boreal forest streams are characterized by large volumes of instream wood, yet the relationship between logjams and Pacific salmon productivity remains underqualified. We located logjams (</span><i>n</i><span> = 427) within the distribution of Chinook salmon (</span><i>Oncorhynchus tshawytscha</i><span>) in the Chena River, Alaska (Yukon River tributary) and measured dimensions, classified formative process, and snorkel-sampled a subset (</span><i>n</i><span> = 189) of logjams to detect and count juvenile salmon relative to multiscale variables and a dam. Logjam size increased downstream, whereas logjam density and large wood recruits declined (upstream = 6 logjams/km, 33 recruits/km; downstream = 0.3 logjams/km, 6 recruits/km), particularly below a dam that reduced downstream wood transport and log-trapping locations (i.e., bars). Juvenile salmon occupied 68% of logjams; mid-network logjams had the highest densities (mean = 0.85 fish/m</span>²<span>). We modeled juvenile salmon counts with logjam-, stream reach-, and neighborhood-scale (&gt; 1 km) predictors. Covariates that best predicted juvenile salmon densities included bankfull flow and stream power at reach scales in addition to growth potential, spawning habitat quality, and logjam area within 1 km of the focal logjam at neighborhood-scales. Multiscale perspectives that link landscape characteristics, wood dynamics, and instream modifications with juvenile salmon production will be important to facilitate conservation and management of boreal streams.</span></p> application/pdf 10.1002/rra.4387 en Wiley Multiscale processes drive formation of logjam habitats and use by juvenile Chinook salmon across a boreal stream network in Alaska article