White Sturgeon – Oregon Conservation Strategy

Overview

Species Common Name White Sturgeon
Species Scientific Name Acipenser transmontanus
SMU/ESU/DPS/Subspecies Lower Columbia/Coastal SMU

Ecoregions

Coast Range

Oregon’s Coast Range, known for its dramatic scenery, is extremely diverse, with habitats ranging from open sandy dunes to lush forests and from tidepools to headwater streams. It follows the coastline and extends east through coastal forest to the border of the Willamette Valley and Klamath Mountains ecoregions

West Cascades

The West Cascades ecoregion extends from east of the Cascade Mountains summit to the foothills of the Willamette, Umpqua, and Rogue Valleys, and spans the entire length of the state of Oregon. It is largely dominated by conifer forests, moving into alpine parklands and dwarf shrubs at higher elevations.

Willamette Valley

The Willamette Valley ecoregion is bounded on the west by the Coast Range and on the east by the Cascade Range. This long mostly level alluvial plain has some scattered areas of low basalt, and contrasts with productive farmland and large urban areas. It has the fastest-growing human population in the state resulting in challenges due to land-use changes.

Nearshore

The Nearshore ecoregion includes a variety of habitats ranging from submerged high-relief rocky reefs to broad expanses of intertidal mudflats in estuaries and hosts a vast array of fish, invertebrates, marine mammals, birds, plants, and micro-organisms. This ecoregion encompasses the area from the outer boundary of Oregon’s Territorial Sea to the supra-tidal zone, and up into the estuaries.

Special needs

Nearshore coastal waters, estuaries, and spawning and rearing habitats below Bonneville Dam and Willamette Falls are essential.

Limiting factors

Long-lived, late-maturing species with relatively low population size. Habitat: Limited spawning habitat. In-water work effects, including dredging and ocean/estuarine energy projects, as well as navigation. Hydro-system impacts, including direct mortality, dewatering of early life history stages associated with load following and power peaking water fluctuations, and blocked access to historic range. Harvest: Lower Columbia River white sturgeon are subject to a variety of fisheries, and over-harvest could negatively impact lower Columbia River white sturgeon. In addition to regulated fisheries white sturgeon may be subjected to significant illegal harvest due to the monetary value of their roe. Predators: Steller Sea Lion predation, harassment on- and displacement from-spawning grounds.

Data gaps

Life history, migration, and diet of sub-adults and juveniles. Movements and habitat use in rivers, estuaries and nearshore areas. Impacts of global climate change and availability of native forage species (e.g., Pacific Lamprey and Eulachon). Magnitude of impact from illegal harvest, and the effects (lethal and sub-lethal) of pinniped predation and harassment on sturgeon habitat use and reproduction.

Conservation actions

Use species-specific population assessments and habitat requirements to guide management actions. Minimize incidental catch and bycatch in fisheries (nearshore ocean, estuaries, and freshwater). Ensure that development and other non-fishery, human related activities do not occur in habitat (space and time) or result in direct mortality that may result in negative impacts. Monitor to understand the effects of pinniped predation/harassment.

Key reference or plan

Lower Columbia River and Oregon Coast White Sturgeon Conservation Plan: https://www.dfw.state.or.us/fish/CRP/docs/lower_columbia_sturgeon/LCR_white_sturgeon_conservation_plan.pdf