Atlantic salmon is a species of ray-finned fish that belongs to the Salmonidae family. It is a highly sought after fish due to its rich taste and nutritional value.
Atlantic salmon have a complex life history that begins with spawning and juvenile rearing in rivers.
Read on below to learn all about these fascinating fish!
Table of Contents
Habitat and Distribution
Atlantic salmon are anadromous fish, meaning they live in both freshwater and saltwater environments.
They hatch and spend the first few years of their life in freshwater streams and rivers.
They prefer streams with gravel bottoms where they can lay their eggs.
Once they reach a certain size, Atlantic salmon migrate to the ocean where they spend the majority of their adult life.
They can be found in the North Atlantic from North America to Europe and up into the Baltic Sea.
In North America, they were historically found in rivers from Maine to Connecticut, but populations have declined significantly due to overfishing, habitat loss, and pollution.
Atlantic salmon are native to the northern Atlantic Ocean, from the Arctic Circle to Portugal in the eastern Atlantic, from Iceland and southern Greenland, and from North America to Europe.
They have also been introduced to other areas, including the Great Lakes in North America and parts of South America.
In Alaska, Atlantic salmon are considered an invasive species and have been found in a few locations, although there is no evidence of reproduction.
Atlantic salmon are generally large fish that can weigh between 8 to 12 pounds. However, sea-run Atlantic salmon can attain a larger size than landlocked salmon.
The largest Atlantic salmon ever recorded weighed 79.5 pounds and was caught in Norway.
The coloration of Atlantic salmon varies depending on their environment. Freshwater salmon have a dark greenish-blue back and silver sides with black spots.
As they migrate to the sea, their coloration changes to a bright silver with a blue-green back.
During spawning, their coloration changes again to a dark reddish-brown with black spots.
The life cycle of Atlantic salmon is complex and fascinating. They are born in freshwater streams and rivers, then migrate to the sea where they spend most of their life.
After two to four years, they return to their natal stream or river to spawn. The female salmon lays eggs in a nest called a redd, and the male fertilizes them.
The eggs hatch into alevins, which eventually become fry. The fry then migrate to the sea to start the cycle again.
It is important to note that the life cycle of Atlantic salmon is threatened by human activities such as overfishing, pollution, and habitat destruction.
Conservation efforts are necessary to protect this species and ensure their survival for future generations.
Ecology and Behavior
The Atlantic Salmon is an opportunistic feeder, meaning it eats a wide variety of prey depending on what is available.
Young salmon feed on small invertebrates such as insects, while adult salmon feed on fish, squid, and crustaceans.
They are also known to eat shrimp, krill, and plankton. Atlantic Salmon are known to be active feeders, and they can consume up to 5% of their body weight in a single day.
Salmon are also known to have a strong sense of smell, which helps them locate prey in the water.
They use their sense of smell to detect the scent of prey, which they then track down and consume.
Mating and Reproduction
Atlantic Salmon are anadromous, meaning they migrate from the sea to freshwater rivers to spawn.
During the breeding season, males develop a hooked jaw and a hump on their back, while females develop a swollen belly.
The males compete for the attention of the females, and the strongest males are usually the ones to mate.
After mating, the female will lay her eggs in a nest she has created in the riverbed. The male will then fertilize the eggs, and the female will cover them with gravel to protect them.
The eggs will hatch after a few months, and the young salmon will emerge from the gravel and begin their journey downstream to the ocean.
The migration of the Atlantic Salmon is a remarkable feat of endurance and strength. After hatching in freshwater rivers, young salmon will spend several years in the river before migrating downstream to the ocean.
Once in the ocean, they will spend several years feeding and growing before returning to the river to spawn.
During their migration, salmon face many challenges, including predators, dams, and pollution.
Despite these challenges, the Atlantic Salmon has developed remarkable adaptations to help them navigate their environment, including their sense of smell, their ability to jump over obstacles, and their ability to swim against strong currents.