Atlantic Salmon (Inner St. Lawrence population – DU10)

Salmo salar

SARA Status
No Status
NS
Special Concern
SC
Threatened
TH
Endangered
EN
Extirpated
EX

SARA Status

  • No Status NS
  • Special Concern SC
  • Threatened TH
  • Endangered EN
  • Extirpated EX
COSEWIC Status
Not at Risk
NR
Special Concern
SC
Threatened
TH
Endangered
EN
Extirpated
EX

COSEWIC Status

  • Not at Risk NR
  • Special Concern SC
  • Threatened TH
  • Endangered EN
  • Extirpated EX

Description

The Atlantic Salmon has a fusiform body shape that is somewhat compressed laterally and has an average length of about 457 mm. Its back is blue-green, its sides are silvery with several markings that are either round or x-shaped, and its belly is white. During the reproduction period, the Atlantic Salmon loses its silver colour and takes on a greenish or reddish hue; a few large, white-edged spots then appear on its sides.

Habitat

Atlantic Salmon spawn in fresh water, generally in their native river. Juveniles spend one to eight years in fresh water before migrating to salt water in the North Atlantic. After staying at sea for one to four years, adults return to fresh water to spawn. Salmon rivers are generally clear, cool and well oxygenated, with gravel, cobble and boulder substrates.

Because Atlantic Salmon have a high degree of fidelity to their natal rivers and given their adaptation to the stream they frequent (e.g., difference in morphology, life cycle and behaviour), the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) has identified 16 designatables units (DU) of Atlantic Salmon, 11 of which are considered at risk. Atlantic Salmon of the Inner St. Lawrence population (DU10) reproduce in the tributaries of the St. Lawrence River's north shore between the Bras des Murailles River and the Jacques Cartier River as well as in the Ouelle River on the St. Lawrence River's south shore. This population has nine known salmon rivers.

Threats

The causes of the widespread decline of Atlantic Salmon are not well understood. Several major reviews have attempted to identify and prioritize the causes of this situation. The low rate of survival at sea was cited as the primary cause of the decline. The populations are also threatened by climatic changes and environmental changes in the ocean; Aboriginal, recreational and illegal fishing; obstacles in fresh water (e.g. dams); agriculture; urbanization; aquaculture and invasive species. In some cases, the habitat used for freshwater spawning is degraded.

The small size of the Inner St. Lawrence population (about 5,000 individuals in 2008) is cause for concern. The number of small (that spent one winter at sea) and large (that spent more than one winter at sea) fish has remained fairly stable over the past three generations. Because this region's rivers are near urban centres, this population experienced a serious decline due to habitat loss.

Further Information

The Atlantic Salmon commercial fishery was closed progressively in Canadian waters from the mid-1980s until the complete closure in 2000. Aboriginal peoples continue to fish in several salmon rivers for food, social and ceremonial purposes. Salmon represents an important cultural tradition to which they attach great value. Lastly, recreational fishing is still authorized. Restrictive management measures are imposed for each river based on abundance estimates. These measures include catch limits, mandatory release of large salmon to the water, and closures of certain watercourses. Salmon habitat is protected under the fish habitat protection provisions of the Fisheries Act.

Visit the Species at Risk (SARA) Public Registry.

Atlantic Salmon (Inner St. Lawrence population – DU10)

Atlantic Salmon

Scientific name: Salmo salar
SARA Status: No Status
COSEWIC Status: Special Concern (November 2010)
Region: Quebec

map

Distribution range for the Inner St. Lawrence population of Atlantic Salmon
S. Proulx, DFO 2012

Salmon life cycle

Salmon life cycle

Did You Know?

Despite relatively stable trends, population sizes for salmon of Inner St. Lawrence rivers are relatively low. Many salmon populations in this area have been supplemented by stocking.

School of Atlantic Salmon

School of Atlantic Salmon
D. Danvoye

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