Environmental Trends 2002

Fish

Status of White Sturgeon

Age Distribution of White Sturgeon

NOTES: Lower Fraser River data collected between Mission and Hell’s Gate, mid-Fraser River Data between Boston Bar and Red Rock Creek from May 1995 to October 1999. Nechako River data collected between its mouth and the Nautley River from June 1995 to September 1999.

What is the status of White Sturgeon?

• White Sturgeon are the largest freshwater fish in Canada. They spawn in only three river systems in the world – the Fraser, Columbia and Sacramento, all on the Pacific coast of North America.

• The proportion of juveniles to sub-adults and adults in the population is a good indicator of long-term viability of White Sturgeon. Viable populations are dominated by young Sturgeon. The near absence of juvenile fish indicates repeated spawning failures and an aging population. Such a population may be considered at risk of extirpation.

• All White Sturgeon populations in British Columbia are considered to be threatened; three populations (Nechako, Columbia and Kootenay) are at high risk of extirpation.

• Modifying the natural flow regime with dams can reduce the suitability of rivers for spawning and rearing and is considered the most significant threat. Other significant risk factors include pollution and habitat alteration (through activities such as dredging or gravel mining).

• Recovery planning is underway for Nechako River, and both the Columbia and Kootenay/ Kootenai rivers in partnership with the USA.

For detailed information, including graph data, see In-Depth report [pdf].