St. Lawrence species

Atlantic sturgeon

Acipenser oxyrinchus

Type of resource

  • Bottom fish
  • Fish

Status of the resource

  • Threatened

In season

Fresh in summer and autumn.

SIZE : An average of 1.4 m to 3 m, up to 4.6 m.

LIFE EXPECTANCY : Up to 60 years.

LIFE CYCLE : Sexual maturity, for St. Lawrence Atlantic sturgeon, is between 16 and 24 years for males and around 27 years for females.

In June and July, they migrate to freshwater, where currents are strong or near waterfalls. They spawn on gravelly substrates at depths between 1 m and 3 m. The species does not reproduce every year, but every 3 years or more.

The female can lay up to 4 million slightly sticky eggs. These attach themselves to the substrate and hatch after 3 to 7 days. The young remain in freshwater and migrate to saltwater when they reach a size of 80 cm to 120 cm.

The Atlantic sturgeon has no scales. Instead, it has five rows of triangular bony plates called scutes. Its body is long, and its head is flat.

It has a long, slightly upturned, V-shaped snout with two large double nostrils. Its mouth is small and toothless, with four barbels at the front. The tail is asymmetrical, with a longer upper lobe.

The color of its back varies from olive green to bluish gray and can become almost black. Its belly is white.

Close to the bottom, ideally in a river connected to the sea, between 1 m and 50 m in depth.

Its habitat will vary throughout its life. The Atlantic sturgeon lives in saltwater and migrates to freshwater to spawn. It is an anadromous fish. It favors the sandy or muddy bottoms of the estuary and the Gulf of St. Lawrence.

How do sturgeons use the St. Lawrence estuary?

To find out, scientists tagged over 3,000 Atlantic sturgeon over a period of more than 30 years. The fishermen, who were partners in this project, caught 673 identified Atlantic sturgeons. The vast majority of the sturgeons had traveled less than 35 km from the initial site, showing that they navigate these waters on a very regular basis. A few individuals explored the waters over 600 km away, with a record of 1,307 km, 8 years after their initial capture. In conclusion, the St. Lawrence estuary is the preferred habitat of juvenile and sub-adult (pre-adult) Atlantic sturgeon.




Small crustaceans

Small fish

The sturgeon has few known predators. It can, however, be the prey of lampreys, which will parasitize its organism.


Sea lampreys

MACHINES : Gillnets.


  • Season determined by fishing zone
  • Release of sturgeon measuring over 86 cm

Quebec does not authorize the capture of Atlantic sturgeon for its caviar.

A big fish

The largest Atlantic sturgeon ever caught was a female measuring 4.6 m and weighing 365 kg. This was in 1924, in the estuary of the Saint John River in New Brunswick.

BENEFITS : Atlantic sturgeon is rich in vitamins A, D and B12, as well as in minerals such as phosphorus, potassium, and calcium.

LET’S COOK : High quality firm white flesh.

A flagship product, sturgeon eggs are highly sought-after, as they are the only ones that can be called “caviar”. They are one of the world’s most expensive gourmet products.


  • Given its threatened status, we do not recommend eating sturgeon.