Atlantic salmon | Oceana Canada

Ocean Fishes

Atlantic salmon

Salmo salar

Also known as

Bay salmon, landlocked salmon, outside salmon, spring salmon, ouaniniche, grayling, grilse

Distribution

Throughout the north Atlantic Ocean

Écosystèmes/habitats

Rivers and coastal seas

Feeding Habits

Active predator

Conservation Status

Endangered/Threatened/Special Concern

Taxonomie

Order Salmoniformes (salmon); Family Salmonidae (salmon, trouts, chars)

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Atlantic salmon are an iconic species of the northern Atlantic Ocean and once supported large fisheries throughout their range. They are known for their long, annual migrations from the ocean, up river to freshwater environments where they spawn and lay eggs. Although many wild populations of Atlantic salmon have all but disappeared or have been greatly reduced in the past few decades, Atlantic salmon remains one of Canada’s largest fish exports due to salmon farming, particularly on the Pacific coast of Canada.

Atlantic salmon are easily distinguishable by their pointy head, well developed teeth, and silvery sides speckled with brownish black spots. The colour of their back can vary from browns to greens and blues, becoming bronze-purple in colour with reddish spots during the spawning season. On average, they grow to be about 70 to -75 centimetres in length and weigh about five kilograms, however there have been rare accounts of individuals reaching 13 kilograms in weight

Atlantic salmon have a complex life history which starts when adults come into rivers from the open ocean to spawn every summer and fall, with spawning migrations lasting from June through to November. Salmon also return to the same river systems they were born in year to year, and from generation to generation, in order to spawn. A female will choose a site where the gravel is “just right” in order to “dig” out a nest with her tail. The salmon will then form pairs and spawn over a period of two to three days, with the male guarding both the female and the gravel “nest” during spawning. A female will release 8,000 to 25,000 eggs, which the male will cover with gravel after fertilizing. Eggs hatch after 70 to 160 days, typically in the spring, where they will remain deep in the gravel until their yolk sac has been completely eaten up. As they continue to grow, they will emerge from the gravel and move to shallow pools downstream of where they hatched. They may remain in freshwater environments for one to seven years, however most only stay for two or three years. The salmon will then undergo physiological changes, through a process called smoltification, after which the newly developed juvenile salmon, or “smolts”, will move out into the sea.

Once in the open ocean, Atlantic salmon feed on squids, shrimps and smaller fish. They reach sexual maturity between three and seven years of age and will begin their annual migration inland to spawn and complete the lifecycle. Atlantic salmon, unlike many of their Pacific salmon counterparts, do not always die after spawning and may return to spawn again the following season. These "repeat spawners" are especially important in populations of Atlantic salmon because they are larger and are able to produce more offspring than first time spawners.

Atlantic Salmon were traditionally fished for centuries by First Nations in Eastern Canada and remain a key species for First Nations’ food, social and ceremonial purposes in the Atlantic coast. They were first recorded in commercial fisheries in the mid-1800’s. Atlantic salmon were a readily available and easy to harvest due to their traceable migration patterns, making them a highly valuable fish to Canada’s early economy. Unfortunately, high fishing pressures, damming of rivers and important spawning locations, negative land use practices (such as logging) and acid rain saw early declines in salmon populations in many river systems. The commercial fishery has been closed for decades, however important recreational fisheries still exist in Atlantic Canada and Quebec. Even so, Atlantic salmon is still one of the most readily available and sought-after fish, thanks to it being one of the most commonly farmed marine fish species around the world. Essentially all the Atlantic salmon sold in global markets today is raised in fish farms, with the majority of Canada’s Atlantic salmon farms found on the Pacific Coast.

Due to their nature of spawning in individual river systems and returning to their native river systems every year, many different populations of Atlantic salmon have been identified throughout Atlantic Canada, each with its own individual threats and problems. As such, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) has assessed and listed each population individually, with conservation statuses ranging from Not at Risk to Extinct. The conservation statuses of each population of Atlantic salmon in Canada are as follows:

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