CDC Logo

BC Conservation Data Centre: Conservation Status Report

Acipenser transmontanus
White Sturgeon

 
Scientific Name: Acipenser transmontanus
English Name: White Sturgeon
   
Provincial Status Summary
Status: S2
Date Status Assigned: November 10, 1994
Date Last Reviewed: April 27, 2018
Reasons: White Sturgeon are large-bodied fish that are slow to mature and long-lived. In British Columbia they are restricted to the Fraser, Columbia and Kootenay River systems and in Harrison and Pitt Lakes. Many populations are declining as a result of recruitment failure. Primary threats include habitat degredation from dam construction, changes to flow regimes and fishery by-catch.
 
Range
Range Extent: F = 20,000-200,000 square km
Range Extent Estimate (km2): 46158
Range Extent Comments: White Sturgeon occur in western North America in the Fraser, Columbia and Sacramento-San Joaquin rivers. In British Columbia they occupy the Fraser, Columbia and Kootenay river systems, as well as Harrison and Pitt Lakes. They are primarily freshwater fish; however some individuals enter rivers, estuaries and bays along the coast
(there is no evidence of breeding in coastal rivers). The extent of occurrence in B.C. is 46,158 km2, based on freshwater distribution (COSEWIC 2012f).

COSEWIC (2012f) describes the following 4 designatable units (DU)/populations as follows:
Lower Fraser River population: "...restricted to the Strait of Georgia and the lower Fraser River. It extends from the Fraser Delta to Hells Gate (about 204 river kilometres upstream)."
Upper Fraser River population: "...encompasses about 1,000 km of the mainstem Fraser River between Hells Gate and the confluence of the Morkill and Fraser rivers. There are three geographic groups of sturgeon within the DU: the middle Fraser, upper Fraser, and Nechako River sturgeon groups.
Upper Columbia River population: ??restricted to the mainstem Columbia River between the U.S. border and Revelstoke Dam in British Columbia. Here it encompasses about 425 km of the upper Columbia River. Suggestions of a remnant population between Revelstoke and Mica dams are unconfirmed.?
Upper Kootenay River: ??restricted to Kootenay Lake and the Kootenay River between upstream of Bonnington Falls and the Idaho border with British Columbia. Here it encompasses about 288 km of the Kootenay River (including Kootenay Lake).?
Area of Occupancy Estimate (km2): 5,123
Linear Distance of Occupancy: G = 2,001-10,000
Area of Occupancy Comments: Estimated as 5,123 km2, based on 1 x 1 km grid cells (COSEWIC 2012f)
 
Occurrences & Population
Number of Occurrences: B = 6 - 20
Comments: There are 15 occurrences within the Fraser, Columbia and Kootenay river systems.
Number of Occurrences with Good Viability / Ecological Integrity: Rank Factor not assessed
Number of Occurrences Appropriately Protected & Managed: Rank Factor not assessed
Population Size: F = 10,000 - 100,000 individuals
Comments: There are approximately 11,544 mature individuals: Lower Fraser River: 8,460 (2011); Upper Fraser River: 1,294 (2012); Upper Columbia: 830 (2012); Upper Kootenay: 960 (2012)
 
Threats (to population, occurrences, or area affected)
Degree of Threat: AC = Very high - medium
Comments: The main threats to White Sturgeon are habitat degredation from dam construction and changes to flow regime that appear to cause recruitment failure (COSEWIC 2012f). Threats to each population differ, ranging from Medium to Very High (Upper Columbia: High; Upper Kootenay: Very high-High; Upper Fraser: High-Medium; Lower Fraser: Very High-High (B.C. Conservation Data Centre ND; accessed July 17, 2019). Details on threats for each population can be found in COSEWIC (2012f) and Fisheries and Oceans Canada (2014).

With the exception of the lower Fraser populations, white sturgeon appear to be endangered throughout their historical range in the province, primarily because of flow alteration by dams on the Nechako, Kootenay, and Columbia rivers (Apperson 1992; U.S. Fish and Wildlife Service 1994; Hildebrand 1991; R.L. & L. Environmental Services 1994; D. Ableson, pers. comm. 1992). An apparent decline in the eulachon (THALEICHTHYS PACIFICUS) populations in the lower Fraser River, a major food source for sturgeon, may be a cause for concern there (M. Rosenau, pers. comm. 1992). Loss of productive slough habitat in the Fraser Valley is probably reducing the potential for young sturgeon as well (Lane 1994). Contamination with heavy metals and other pollutants is also of concern. Recent unexplained deaths of large fish in the lower Fraser are a serious concern.
 
Trend (in population, range, area occupied, and/or condition of occurrences)
Short-Term Trend: Rank Factor not assessed
Comments: Short-term Trends for individual populations range from a decline of 10% to over 50% (Upper Columbia: 30-50%; Upper Kootenay: >50%; Upper Fraser: 10-30%; Lower Fraser: 30-50%) (B.C. Conservation Data Centre ND; accessed July 17, 2019).

Populations in the Fraser below Quesnel are producing young, but there has been a significant decline in the number of juveniles appearing in the fishery in recent years (M. Rosenau, pers. comm.). Certainly they are much less abundant in the lower Fraser than they were historically (Lane 1991). Other populations such as those in the Nechako, Kootenay and Columbia rivers are even more threatened, with few or no young being produced or surviving in recent years (Apperson 1992; Hildebrand 1991; R.L. & L. Environmental Services 1994; D. Ableson, pers. comm. 1992).
Long-Term Trend: Rank Factor not assessed
Comments: Long-term Trends for individual populations range from a decline of 10% to >90% (Upper Columbia: >50%; Upper Kootenay: >90%; Upper Fraser: 10-30%; Lower Fraser: 50-90%) (B.C. Conservation Data Centre ND; accessed July 17, 2019).
 
Other Factors
Intrinsic Vulnerability: Rank Factor not assessed
Environmental Specificity: Rank Factor not assessed
Other Rank Considerations:
 
Information Gaps
Research Needs:
Inventory Needs:
 
Stewardship
Protection:
Management:
 
Version
Author: Cannings, S.G. and L. Gelling
Date: July 17, 2019
 
References
Apperson, K. 1992. Kootenai River white sturgeon status report. Unpubl. rep., Idaho Dep. Fish and Game, Coeur d'Alene, ID. 3pp.
Dixon, B.M. 1986. Age, growth and migration of white sturgeon in the Nechako and upper Fraser rivers of British Columbia. Fish. Tech. Circ. No. 70, B.C. Minist. Environ., Prince George.
ECL Envirowest Consultants Ltd. 1992. Fraser River White Sturgeon, radio tracking and tissue sampling, 1989-1992. Prepared for Ministry of Environment, Lands and Parks, Surrey, B.C.
Fleck, J.L., and H. Andrusak. 1977. Length and ages of Kootenay River white sturgeon. Unpubl. rep., Fish and Wildl. Program, B.C. Environ., Nelson.
Hildebrand, L. 1991. Lower Columbia River fisheries inventory: 1990 studies. Vol. 1, Main Report. Submitted to B.C. Hydro, Environmental Resources, Vancouver. 170 pp.
Lane, E.D. 1991. Status of the white sturgeon, ACIPENSER TRANSMONTANUS, in Canada. Canadian Field-Naturalist 105:161-168.
Lane, E.D. 1994. The conservation of sturgeon stock in the lower Fraser River watershed. Draft rep. for the Habitat Conservation Fund, Victoria, B.C.
R.L. &L. Environmental Services Ltd. 1994. Status of white sturgeon in the Columbia River, B.C. Final report for B.C. Hydro, Environ. Affairs, Vancouver.
Swiatkiewicz, V.J. 1989. Lower Fraser River white sturgeon (Acipenser transmontanus) studies from 1985-1987. Reg.l Fish. Rep. No. LM209, B.C. Minist. Environ., Surrey.
U.S. Fish and Wildlife Service. 1994. Endangered and threatened wildlife and plants; determination of endangered status for the Kootenai river population of the white sturgeon. Federal Register 59:45989.
 

Please visit the website Conservation Status Ranks for information on how the CDC determines conservation status ranks. For global conservation status reports and ranks, please visit the NatureServe website http://www.natureserve.org/.

Suggested Citation:

B.C. Conservation Data Centre. 2019. Conservation Status Report: Acipenser transmontanus. B.C. Minist. of Environment. Available: https://a100.gov.bc.ca/pub/eswp/ (accessed Jan 24, 2025).