The Laurentian ChannelGeographical Names of Canada - Laurentian Channel
/ref> is a deep

submarine A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or infor ...

valley off the coast of eastern

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

in the

Gulf of Saint Lawrence The Gulf of St. Lawrence is a gulf that fringes the shores of the provinces of Quebec, New Brunswick, Nova Scotia, Prince Edward Island, Newfoundland and Labrador, in Canada, plus the islands Saint-Pierre and Miquelon, possessions of France, in ...

The channel is of glacial origin and is the submerged valley of the historic

Saint Lawrence River The St. Lawrence River (, ) is a large international river in the middle latitudes of North America connecting the Great Lakes to the North Atlantic Ocean. Its waters flow in a northeasterly direction from Lake Ontario to the Gulf of St. Lawrenc ...

, running from a sharp escarpment downstream from the confluence of the St. Lawrence with the Saguenay River, past Anticosti Island and through the Gulf of St. Lawrence to the edge of the

continental shelf A continental shelf is a portion of a continent that is submerged under an area of relatively shallow water, known as a shelf sea. Much of these shelves were exposed by drops in sea level during glacial periods. The shelf surrounding an islan ...

off the island of

Newfoundland Newfoundland and Labrador is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region of Labrador, having a total size of . As of 2025 the population ...

. Its depth ranges from with sub-tidal shelves on each side of the channel ranging in depths of less than . The channel ranges from a minimum width of to as much as at the Laurentian fan which is located at the edge of the continental shelf. Deep waters with temperatures between enter the Gulf at the continental slope and are slowly advected up the channel by estuariane circulation. Over the 20th century, the bottom waters of the end of the channel (i.e. in the Saint Lawrence estuary) have become hypoxic.

Ecological importance

The Laurentian Channel is an ecologically important area, providing critical habitat for a variety of marine species, some of which are fished commercially and others that are not. Non-commercial species are part of the marine ecosystem in the area. The Laurentian Channel contains the highest concentration of black dogfish in Canadian waters and is the only place where pupping occurs. It is an important spawning, nursery, and feeding area for a variety of species including porbeagle shark and

smooth skate The Anacanthobatidae, the smooth skates or leg skates, are a family of skates found at depths below in the Indian, Pacific and Atlantic Oceans. They lack the dorsal denticles (sharp, tooth-like scales) of other rays, hence their name, from G ...

. Porbeagle sharks and basking sharks move into the area in the spring and reside there throughout the summer. One of only two known porbeagle shark mating grounds occurs within the channel. Two species at risk, the northern wolffish and the leatherback sea turtle, have been found in the area. In addition, at least 20 species of whales and dolphins have been observed in the area, as it is a critical feeding area and migration route into and out of the Gulf of St. Lawrence. The Laurentian Channel contains significant

coral Corals are colonial marine invertebrates within the subphylum Anthozoa of the phylum Cnidaria. They typically form compact Colony (biology), colonies of many identical individual polyp (zoology), polyps. Coral species include the important Coral ...

and sea pen populations, representing sensitive

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from the Ancient Greek word (), meaning "the depths". ...

habitats. Coral and sea pens are important to the ecosystem and depend on the integrity of the sands and muds in the area for their survival. Of the variety of coral species found in the area, sea pens have been recorded in the greatest numbers and diversity, with the Laurentian Channel being described as having the highest sea pen concentrations within the entire Newfoundland and Labrador Shelves Bioregion.

Laurentian Channel Marine Protected Area

A portion of the Laurentian Channel was identified as an Ecologically and Biologically Significant Area (EBSA) in 2007. On June 8, 2010, the Minister of Fisheries and Oceans Canada announced the Laurentian Channel as an Area of Interest (AOI). The AOI encompasses a portion of Laurentian Channel located off the southwest coast of Newfoundland and Labrador, an area of . In June 2017, Fisheries and Oceans Canada (DFO) proposed the Laurentian Channel AOI as a Marine Protected Area (MPA) under the '' Oceans Act''. In April 2019, Fisheries and Oceans Canada designated the Laurentian Channel Marine Protected Area (MPA). The main purpose of the Laurentian Channel Marine Protected Area is to protect the biodiversity of the region. This MPA explicitly protects porbeagle sharks, smooth sakes, basking sharks, black dogfishes, northern wolffish, and leatherback sea turtles, along with sea pens and other cold water coral. Atlantic cod is not officially protected, the Laurentian Channel MPA could encompass a possible spawning ground. Much is still to be discovered regarding the life cycle of Atlantic cod which makes it a difficult species to protect using smaller, specific MPAs (

SLOSS Debate The SLOSS debate was a debate in ecology and conservation biology during the 1970's and 1980's as to whether a single large or several small (SLOSS) reserves were a superior means of conserving biodiversity in a habitat fragmentation, fragmented ha ...

). Thus, due to the large, undivided size of the Laurentian Channel MPA, the chance of protecting the region where Atlantic cod spawn is significantly higher.

References

External links

Will "Dead Zones" Spread in the St. Lawrence River? - Department of Fisheries and Oceans
{{Authority control Valleys of Canada Marine Protected Areas of Canada

Ecological importance

Laurentian Channel Marine Protected Area

See also

References

External links