St. Lawrence Estuary Area of Interest

Fisheries and Oceans Canada has selected the St. Lawrence Estuary as an Area of Interest (AOI) for potential designation as a Marine Protected Area (MPA) under the Oceans Act. The purpose of this Marine Protected Area is to ensure the long-term conservation and protection of marine mammals that are year-round residents of the St. Lawrence Estuary (beluga whale and harbour seal) or seasonal migrants (blue whale), as well as their habitats and food resources.

Following consultations with interested parties and the general public, DFO worked with the marine transportation industry and Parks Canada to implement voluntary measures to reduce the risk of collisions with whales in the St. Lawrence Estuary, including a reduction in speed. DFO also worked with the marine mammal observation industry to define regulatory measures for this industry.

An analysis to determine the progress made in protecting marine mammals in the estuary is planned. Fisheries and Oceans Canada would also like to identify tools that could fill in any gaps to reach conservation objectives for the area.

Geographic Boundaries

The area covered by the Area of Interest totals approximately 6,000 km2 and corresponds to the summer range of the beluga whale, to the large majority of sites used by the harbour seal population of the St. Lawrence Estuary, and to large blue whale feeding grounds. It coincides with the part of the St. Lawrence in which pressure on marine mammals is the highest.

Estuaire du St-laurent

The Area of interest is adjacent to the Saguenay–St. Lawrence Marine Park, a national marine conservation area created in 1998. It does not include the territory of the marine park, but is complementary to it.

Marine Mammals

The St. Lawrence Estuary, an essential ecosystem

The St. Lawrence Estuary contains high concentrations of krill and capelin, making it a feeding ground of critical importance for many species of marine mammals. Every year, large numbers of cetaceans, including large whales, migrate to the area to feed and build up their energy reserves for the breeding season.

The St. Lawrence Estuary is also an important habitat for beluga whales and harbour seals, which inhabit the estuary year round. The wide diversity and high density of marine mammal species found in the estuary, the proximity of watching sites and the relatively calm waters of the estuary make it one of the best sites in the world for watching marine mammals.

Status of marine mammals

About a dozen marine mammal species are regular or occasional visitors to the estuary, mostly on a seasonal basis. Of that number, close to half are species at risk according to the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and are or could be protected under the Species at Risk Act (SARA). They include the blue whale (endangered), St. Lawrence River beluga (threatened) and fin whale (special concern).

Aquatic Species at Risk in Quebec
Fisheries and Oceans Canada – regional website (Quebec)

Committee on the Status of Endangered Wildlife in Canada


Marine mammals in the St. Lawrence Estuary are exposed to many threats due to human activity: disturbance or destruction of their habitat, exposure to toxic chemical materials, risks of collision with ships, exposure to noise and disturbance.


Report on the Public Consultation on the St. Lawrence Estuary Marine Protected Area (MPA) Project – March 2010 (PDF only)

Additional Information:

Proceedings from a Scientific Workshop on Marine Mammals, their Habitats and Food Resources – 2008 (PDF only)

Links of Interest

For more information about the ecology and health of marine mammals that occur in the St. Lawrence Estuary and the threats facing them, please refer to the following sites and articles.


Baleines en direct (in French only)
Group for Research and Education on Marine Mammals (GREMM)

Center of Expertise in Marine Mammalogy (CEMAM)
Fisheries and Oceans Canada

Saguenay–St. Lawrence Marine Park (SSLMP)

Réseau d’observation des mammifères marins (ROMM) (in French only)


A Natural Food Storehouse for Whales – The Result of a Fragile and Unique Ocean Equilibrium
Feature article, DFO Science – February 2011

Pollution a Possible Culprit in the Threatened Status of a Beluga Population
Feature article, DFO Science – July 2010

Contact Us

Oceans Management Division
Fisheries and Oceans Canada
850 route de la Mer, P.O. Box 1000
Mont-Joli, Quebec, G5H 3Z4
Telephone : 418-775-0854
E-mail :