Summary White Sturgeon, Acipenser transmontanus (WS), are distributed throughout three major river basins on the West Coast of North America: the Sacramento‐San Joaquin, Columbia, and Fraser River drainages. Considered the largest North American freshwater fish, some WS use estuarine habitat and make limited marine movements between river basins. Some populations are listed by the United States or Canada as threatened or endangered (upper Columbia River above Grand Coulee Dam; Kootenai River; lower, middle and, upper Fraser River and Nechako River), while others do not warrant federal listing at this time (Sacramento‐San Joaquin Rivers; Columbia River below Grand Coulee Dam; Snake River). Threats that impact WS throughout the species’ range include fishing effects and habitat alteration and degradation. Several populations suffer from recruitment limitations or collapse due to high early life mortality associated with these threats. Efforts to preserve WS populations include annual monitoring, harvest restrictions, habitat restoration, and conservation aquaculture. This paper provides a review of current knowledge on WS life history, ecology, physiology, behavior, and genetics and presents the status of WS in each drainage. Ongoing management and conservation efforts and additional research needs are identified to address present and future risks to the species.

To understand links between substrate and recruitment of white sturgeon ( Acipenser transmontanus ), I evaluated the effects of substrate condition on larval drift, hiding, and predation between hatch and 15 days posthatch (dph). Over porous substrates (small gravel = 1.2–1.9 cm; medium gravel = 2.5–5.0 cm; cobble = 10–15 cm), rapid interstitial hiding was observed from 0 to 6 dph at low water velocity (4 cm·s–1), whereas larvae drifted in response to nonporous substrates (sand < 0.2 cm; embedded cobble). Velocities of 20 cm·s–1 led to significantly lower drift only at 1 dph over small gravel. Hiding occurred an average of 2.0–13.3 s after release at 0–6 dph. Predation by sculpins ( Cottus  spp.) on larval sturgeon also decreased significantly in response to porous substrates at 1 dph. The strongest expression of increased hiding and decreased predation when small gravel was available suggests that yolksac larvae prefer small interstitial spaces created by that substrate. Considering behavioural responses in preferred natural spawning habitat suggests yolksac larvae predominantly hide in the vicinity of spawning locations. Identification of strong effects of substrate condition on age-specific drift and survival suggests that substrate degradation may contribute to recruitment limitations for sturgeon.

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