Atlantic Sturgeon St. Lawrence populations
Scientific Name: Acipenser oxyrinchus
Other/Previous Names: Atlantic Sturgeon (Great Lakes / St. Lawrence populations)
Taxonomy Group: Fishes
Range: Quebec, Atlantic Ocean
Last COSEWIC Assessment: May 2011
Last COSEWIC Designation: Threatened
SARA Status: No schedule, No Status
Image of Atlantic Sturgeon
The Atlantic Sturgeon is a large-bodied, slow-growing and late-maturing anadromous fish, which lives and grows in brackish, salty water, but spawns in fresh water. The largest fish to be captured in the St. Lawrence River (160 kg or 350 lb) was estimated to be about 60 years old.
Distribution and Population
According to the Committee on the Status of Endangered Wildlife in Canada, Atlantic Sturgeon found in Canadian waters form two distinct populations: the St. Lawrence and Maritimes populations. The Atlantic Sturgeon, St. Lawrence populations, is mainly found east of Trois-Rivières, into the Estuary and past the Gulf of St. Lawrence, into the Atlantic up until Ungava Bay in the north, and along the northeastern coast of Newfoundland in the south. The species gathers in areas between Québec City and Petite-Rivière-Saint-François to rear and feed their young, and potentially so adults can spawn, rest and feed as well. The current population size of Atlantic Sturgeon, St. Lawrence populations, has never been formally established but the population of mature adults is estimated at between 500 and 1000 individuals.
The Atlantic Sturgeon lives and grows in brackish and salty water, but spawns in fresh water. The transition zone between fresh water and salt water in the St. Lawrence estuary is home to groups of benthic prey preferred by the Atlantic Sturgeon and is an important habitat for the breeding and feeding of juveniles. The Atlantic Sturgeon feeds primarily on benthic invertebrates, although large juveniles and adults also feed on small fish.
In the St. Lawrence River, males reach sexual maturity between the ages of 16 and 26, while females may reach maturity around age 27 or 28. Because of its large size, the female Atlantic Sturgeon is extremely fertile. A 148-kg female was reportedly captured in the St. Lawrence River with 41.4 kg ovaries containing about 3,700,000 eggs. The Atlantic Sturgeon does not spawn every year. Males probably reproduce every 3 to 4 years, while this interval is longer for females. In the St. Lawrence River, spawning occurs in June and July, after which the adults migrate further downstream in the Estuary and the Gulf. Juveniles begin their migration once they have reached 80 to 120 cm.
The main threats to the Atlantic Sturgeon are commercial fishing and the degradation and loss of habitat. Dredging could constitute a major threat, especially in juvenile feeding areas. Marine and fresh water pollution was also identified as a potential threat to the Atlantic Sturgeon's habitat.
Provincial and Territorial Protection
PLEASE NOTE: Not all COSEWIC reports are currently available on the SARA Public Registry. Most of the reports not yet available are status reports for species assessed by COSEWIC prior to May 2002. Other COSEWIC reports not yet available may include those species assessed as Extinct, Data Deficient or Not at Risk. In the meantime, they are available on request from the COSEWIC Secretariat.
4 record(s) found.
- COSEWIC Status Reports (1 record(s) found.)
- Response Statements (1 record(s) found.)
- COSEWIC Annual Reports (1 record(s) found.)
- Consultation Documents (1 record(s) found.)
COSEWIC Status Reports
COSEWIC Annual Reports
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