SARA Status: Endangered, Listed under SARA (2006) COSEWIC Status: Endangered (2003)
White Sturgeons have a long lifespan, sometimes greater than 100 years, suggesting they have a limited ability to adapt to rapid environmental changes. These fish are specifically adapted to the large river systems of western Canada and the United States, where they have evolved for millions of years.
The toothless White Sturgeon captures its prey by extending its mouth to reach out and engulf it whole.
Spawning for White Sturgeon occurs in the late spring and early summer. Less than a month after hatching, larvae transform themselves into juvenile fish, or fry, resembling miniature adults.
White Sturgeon is the largest and longest-lived freshwater fish species in North America. The species’ most distinguishing features include a mainly cartilaginous skeleton, a long scaleless body covered with rows of large bony plates (called scutes) on the back and sides, a shark-like tail, and four barbels between the mouth and an elongated snout. Fish of over 6m in length and over 100 years of age have been reported in the Fraser River.
Though they move into shallower areas briefly to feed in spring and summer, adults are typically found in deep near-shore areas of major rivers, adjacent to heavy and turbulent flows, with sandy or fine gravel bottom. In winter, Sturgeon prefers calmer areas. Generally, juveniles prefer lower reaches of tributaries, wetlands and side channels.
Over the past century, White Sturgeon populations have been reduced by threats such as over-fishing, construction of hydroelectric facilities, habitat loss from floodplain development, reduced food resources, and pollution.
In Canada, the species is found only in British Columbia, where there are six distinct populations: one each in the lower, middle and upper reaches of the main stem of the Fraser River, one in the Nechako River, one in the Columbia River watershed, and one in the Kootenay River watershed.
Long-term data on fluctuations in population size are generally lacking for all White Sturgeon populations because most studies are relatively recent. Several lines of evidence point out that population size has declined in many parts of the Canadian range, particularly in the Nechako, Columbia and Kootenay rivers.
In 1994, commercial and sport harvests of White Sturgeons were closed and First Nations people voluntarily stopped their sustenance harvests. This important step allowed more fish to survive and reproduce, and helped to slow the decline of some populations. Valuable community outreach and stewardship programs have also emerged from the efforts and commitment of public groups such as the Fraser River Sturgeon Conservation Society. Focused conservation and recovery efforts involving government, First Nations, industry, and others were initiated for all populations beginning in the late 1990s. Stakeholders will continue to be engaged in conservation and recovery efforts for White Sturgeon.
Six populations of this species have been identified as Endangered by the Committee on the Status of Endangered Wildlife in Canada. Four of these populations including the Kootenay, Nechako, Upper Columbia, and Upper Fraser river White Sturgeon are listed under the federal Species at Risk Act.
Listing under the Species at Risk Act provides protection to White Sturgeon individuals and their critical habitat. All White Sturgeon populations, listed or not listed, will also continue to be carefully managed under the Species at Risk Act and the Fisheries Act. A comprehensive recovery strategy is in development for all listed populations and will be followed by an action plan which will outline the projects or activities required to meet the goals and objectives of the recovery strategy.
Scientific Name: Acipenser transmontanus
Taxonomy: Fishes (freshwater)