Skip booklet index and go to page content

COSEWIC Assessment and Update Status Report on the Lake Sturgeon in Canada

Logo of COSEWIC

COSEWIC
Assessment Summary

Western Hudson Bay Populations

Assessment Summary – November 2006

Common name:
Lake sturgeon

Scientific name:
Acipenser Fulvescens (DU1)

Status:
Endangered

Reason for designation:
A precipitous > 98% decline from 1929-1939 has been followed by a slow, steady decline in the Churchill River to the point that records of mature individuals are almost non-existent in the past five years. Historically, overexploitation probably was the primary threat; more recently, dams are probably the most important threat.

Occurrence:
Saskatchewan, Manitoba

Status history:
The species was considered a single unit and designated Not at Risk in April 1986. When the species was split into separate units in May 2005, the "Western populations" unit was designated Endangered. In November 2006, when the Western populations unit was split into five separate populations, the "Western Hudson Bay populations" unit was designated Endangered. Last assessment based on an update status report.

 

Saskatchewan River Populations

Assessment Summary – November 2006

Common name:
Lake sturgeon

Scientific name:
Acipenser Fulvescens (DU2)

Status:
Endangered

Reason for designation:
Seventy-six of 111 historic sites in Saskatchewan and Alberta have been lost and there has been an 80% decline reported in the Cumberland House area from 1960-2001. A 50% decline from 1998 to 2003 has also been reported in the lower Saskatchewan River from Cumberland House to The Pas in Manitoba.

Occurrence:
Alberta, Saskatchewan, Manitoba

Status history:
The species was considered a single unit and designated Not at Risk in April 1986. When the species was split into separate units in May 2005, the "Western populations" unit was designated Endangered. In November 2006, when the Western populations unit was split into five separate populations, the "Saskatchewan River populations" unit was designated Endangered. Last assessment based on an update status report.

 

Nelson River Populations

Assessment Summary – November 2006

Common name:
Lake sturgeon

Scientific name:
Acipenser Fulvescens (DU3)

Status:
Endangered

Reason for designation:
Portions of this designatable unit sustained large commercial fisheries from the early to mid-1900s, during which time there were dramatic declines in landings. More recently, a fishery at Sipiwesk Lake exhibited an 80-90% decline in landings from 1987-2000; and groups of 5-6 spawning fish were observed in the Landing River in 1990 compared to 100s observed several decades ago. Historically, overexploitation probably was the primary threat; more recently, dams probably are the most important threat.

Occurrence:
Manitoba

Status history:
The species was considered a single unit and designated Not at Risk in April 1986. When the species was split into separate units in May 2005, the "Western populations" unit was designated Endangered. In November 2006, when the Western populations unit was split into five separate populations, the "Nelson River populations" unit was designated Endangered. Last assessment based on an update status report.

 

Red-Assiniboine Rivers and Lake Winnipeg Populations

Assessment Summary – November 2006

Common name:
Lake sturgeon

Scientific name:
Acipenser Fulvescens (DU4)

Status:
Endangered

Reason for designation:
A very large commercial fishery existed between the late 1800s and early 1900s. Since then (i.e. in the last 3-5 generations), the species has virtually disappeared from the Red-Assiniboine River and Lake Winnipeg. This was primarily the result of overfishing, although dams probably also affect remnant populations.

Occurrence:
Saskatchewan, Manitoba and Ontario

Status history:
The species was considered a single unit and designated Not at Risk in April 1986. When the species was split into separate units in May 2005, the "Western populations" unit was designated Endangered. In November 2006, when the Western populations unit was split into five separate populations, the "Red-Assiniboine rivers - Lake Winnipeg populations" unit was designated Endangered. Last assessment based on an update status report.

 

Winnipeg River and English River Populations

Assessment Summary – November 2006

Common name:
Lake sturgeon

Scientific name:
Acipenser Fulvescens (DU5)

Status:
Endangered

Reason for designation:
Historically, populations in this designatable unit supported a large commercial fishery. However, there are limited historical and recent data. The limited recent data available show that populations are declining in the Winnipeg River above Seven Sisters Dam, and essentially have disappeared below the dam. Historically, overexploitation probably was the primary threat; now dams and poaching probably are the most important threats.

Occurrence:
Ontario, Manitoba

Status history:
The species was considered a single unit and designated Not at Risk in April 1986. When the species was split into separate units in May 2005, the "Western populations" unit was designated Endangered. In November 2006, when the Western populations unit was split into five separate populations, the "Winnipeg River - English River populations" unit was designated Endangered. Last assessment based on an update status report.

 

Lake of the Woods and Rainy River Populations

Assessment Summary – November 2006

Common name:
Lake sturgeon

Scientific name:
Acipenser Fulvescens (DU6)

Status:
Special Concern

Reason for designation:
Historically, populations in this designatable unit supported a substantial commercial fishery. Although this led to a severe decline, recovery has been sustained since 1970. Dams have not impeded access to important stretches of suitable habitat, but do restrict immigration from the adjacent Winnipeg River.

Occurrence:
Ontario

Status history:
The species was considered a single unit and designated Not at Risk in April 1986. When the species was split into separate units in May 2005, the "Lake of the Woods - Rainy river populations" unit was designated Special Concern. Status re-examined and confirmed in November 2006. Last assessment based on an update status report.

 

Southern Hudson Bay and James Bay Populations

Assessment Summary – November 2006

Common name:
Lake sturgeon

Scientific name:
Acipenser Fulvescens (DU7)

Status:
Special Concern

Reason for designation:
There are limited population data available for populations in this designatable unit and there have been declines in habitat and possibly abundance for some population components related to exploitation and the multitude of dams. The increased access to relatively unimpacted populations and the likelihood of increased hydroelectric development in some areas are causes for concern for this designatable unit.

Occurrence:
Manitoba, Ontario, Quebec

Status history: The species was considered a single unit and designated Not at Risk in April 1986. When the species was split into separate units in May 2005, the "Southern Hudson Bay - James Bay populations" unit was designated Special Concern. Status re-examined and confirmed in November 2006. Last assessment based on an update status report.

 

Great Lakes and Upper St. Lawrence Populations

Assessment Summary – November 2006

Common name:
Lake sturgeon

Scientific name:
Acipenser Fulvescens (DU8)

Status:
Threatened

Reason for designation:
A very large commercial fishery existed in the Great Lakes between the mid-1800s and early 1900s (i.e. 2-3 generations ago) during which time populations of this species were reduced to a small fraction of their original size, and appear to be still at very low levels. Populations appear to be declining in parts of the Ottawa River, and disappearing from many of its tributaries due to dams. There has been a recent decline in the population in the St. Lawrence River probably due to over-exploitation despite recovery efforts. The direct and indirect effects of dams, chemical control of sea lamprey, contaminants and invasive species currently threaten populations.

Occurrence:
Manitoba, Ontario, Quebec

Status history:
The species was considered a single unit and designated Not at Risk in April 1986. When the species was split into separate units in May 2005, the "Great Lakes - Upper St. Lawrence populations" unit was designated Special Concern. Status re-examined and designated Threatened in November 2006. Last assessment based on an update status report.