Atlantic Salmon (Salmo salar)

Atlantic Salmon overview

The Atlantic salmon is a sleek, silvery fish famous for its life cycle: it hatches in cold, clean rivers, migrates to the North Atlantic to grow, then returns, often to the very stream where it was born, to spawn. Young fish pass through stages called alevin, fry, parr and smolt before going to sea, where they feed off Greenland and the Faroe Islands for one to three years. Unlike Pacific salmon, many Atlantic salmon survive spawning and can return to breed again. Wild runs have declined sharply across the range, even as the species has become one of the most farmed fish in the world.

How Long Do Atlantic Salmon Live?

Atlantic salmon typically live 5–8 years, and the oldest recorded reached about 13. A usual life is two or three years in the river followed by one to three years at sea before returning to spawn. Unlike Pacific salmon, some adults, mostly females, survive spawning and come back a second or even third time.

How Much Does an Atlantic Salmon Weigh?

Adult Atlantic salmon returning to rivers usually weigh 3.5–9 kg (8–20 lb). Fish that spent a single winter at sea, called grilse, weigh 1.5–3 kg, while those that stay two or more winters are far heavier. The rod-caught record is 35.9 kg (79 lb), taken from Norway's Tana River in 1928.

How Long Is an Atlantic Salmon?

Adult Atlantic salmon are typically 70–100 cm (28–39 in) long after two years at sea. Grilse returning after one sea-winter measure about 50–65 cm, and the very largest multi-sea-winter fish can reach 1.5 m (5 ft). Landlocked salmon that never go to sea stay much smaller.

How Long Do Atlantic Salmon Eggs Take to Hatch?

Atlantic salmon eggs take roughly 70–160 days to hatch, depending on water temperature. Females bury the eggs in gravel nests called redds in late autumn, and they develop slowly through the winter and hatch in early spring. The hatchlings, called alevins, stay in the gravel for several more weeks living on their yolk sac.

What Do Atlantic Salmon Eat?

Atlantic salmon are carnivores. In rivers, young salmon eat aquatic insect larvae and other small invertebrates; at sea they grow quickly on capelin, sand eels, herring, krill and squid. Once adults re-enter fresh water to spawn they more or less stop eating and live on stored fat.

Diet type: carnivore. Young salmon in rivers eat aquatic insect larvae such as mayflies, caddisflies and blackflies; at sea they switch to capelin, sand eels, herring, krill, amphipods and squid. Returning adults largely stop feeding in fresh water.

Where Do Atlantic Salmon Live?

Atlantic salmon live in cold, clean, gravel-bottomed rivers as juveniles and in the open North Atlantic as growing adults, feeding mainly off Greenland, the Faroe Islands and in the Norwegian Sea. They return to their home rivers to spawn. Some populations are landlocked and spend their whole lives in lakes and their tributaries.

Are Atlantic Salmon Endangered?

The Atlantic salmon was moved from Least Concern to Near Threatened on the IUCN Red List in 2023 after the global population fell by about 23 percent between 2006 and 2020. Threats include dams, pollution, warming rivers and seas, sea lice and escaped fish from salmon farms, and poor survival at sea. US populations are federally endangered.

Near Threatened

Atlantic Salmon fun facts

• Atlantic salmon can leap waterfalls more than 3 m high; the species name salar is often said to come from the Latin for leaper.
• Salmon find their way back to their birth river largely by smell, having imprinted on its chemical signature as young smolts.
• A spent salmon that survives spawning is called a kelt, and some kelts recover at sea and return to spawn again.
• Nearly all Atlantic salmon sold in shops is farmed; commercial fishing for wild Atlantic salmon is banned or tightly restricted in most countries.
• Before heading to sea, a young salmon turns from camouflaged brown with dark bars to bright silver in a transformation called smolting.

Atlantic Salmon FAQ

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