In this post, we will answer the question “Is salmon a saltwater fish?”, we will also learn aspects of the salmon life cycle, as well as its biology and ecology.
Is salmon a saltwater fish?
Yes, the Salmon is a saltwater fish. However, they complete their reproductive cycle in freshwater areas.
Salmon is a large fish of the Salmonidae family, which also includes trout, both of which are very popular today in world cuisine. Its pink-coloured meat appreciably attracts consumers.
There are seven species of salmon: one in the Atlantic Ocean and six in the Pacific Ocean. Atlantic salmon is found mainly in the northern part of the ocean and reproduces in rivers in North America and Europe.
The date on which the first salmon appeared on our planet is still not well known, but it is more or less known that they belong to the teleost fish group and that these dominated the oceans during the Cretaceous. This goes back to when dinosaurs lived, about 135 million years ago.
Since then, salmon has had a very special life cycle compared to other fish. During a long journey of 60 million years, all teleosts spread across the planet and went through evolutionary processes very different from each other.
Life cycle
Salmon, especially from the Atlantic Ocean, has its origins in freshwater, goes to the sea during the winter, generally to northern Europe, and returns in spring to the same place where it was raised, to reproduce there. It is at this very moment that it is imprisoned.
At the time of conception, the male has its head physically altered, the lower jaw takes on a longer, more arched shape, similar to a hook, and the flesh adopts a white colour. The salmon that inhabits the Pacific Ocean dies after spawning, but the Atlantic salmon multiplies at least once more.
After being born freshwater, salmon travel to the ocean, where they live for one to three years. It then returns to its birthplace to reproduce. Some salmon travel more than 3,200 kilometres on this journey. To reach their place of origin, they must swim against the current, overcoming waterfalls and churning rapids.
Once in freshwater, the salmon stops eating and stays alive due to the accumulated fat in the body. Males fight, vying for a mate. After mating, the female digs a hole and lays thousands of eggs in it.
The spawn
The spawn usually occurs in late summer or autumn. Egg incubation is completed in winter, after a time that varies, depending on the temperature, from 60 to 200 days.
The female uses her tail to swing it and build a nest of 40 to 50 centimetres. Sometimes, when other males try to enter the nest the female is building, the female acts violently to drive out the intruders. This nest building takes a few hours, as the female chooses and gathers the stones that seem most suitable to her to form the “cradle” where the new salmon will be born. In addition, they can build up to five nests while checking their quality and depth.
Once the nests are built, the female allows the male to be beside her so that, at the same time, the female releases the eggs and the male the sperm. In this way, fertilization takes place. When water comes out of the seminal fluid, the female looks at the eggs at the bottom of the nest and runs to cover them while she wags her tail like a fan. This move is done without touching any rocks and is done to create a chain that moves the eggs to the gravel to avoid damage and to keep them well protected.
As the action ends in one nest, it builds the next. In each one is depositing between 500 and 1000 eggs. Over the next few days, he covers them to protect them from death.
In the Pacific salmon species, both the male and the female, with procreation guaranteed, seem to lose interest in life and abandon themselves to floating in the current, only to die soon after. The Atlantic salmon is able, however, to swim once more to the sea. The spawning sites may not be too far away, but some Pacific salmon, such as Oncorhynchus keta and O. tshawytscha, travel more than three thousand kilometres down the Yukon River in Alaska to spawn near their sources.
Salmon Farming
The cultivation and rearing of salmon began around 11,500 years ago in North America by primitive men who lived in caves.
Chile and Norway are countries with ice and crystalline waters, both with low population density, which is the main reason for the salmon industry to be located in these places.
Raising Salmon
Salmonidae like cold water, spending part of their lives in rivers and lakes and then heading to the sea. The breeding cycle of this animal begins when the females lay their eggs among the rocks of the river so that, when the young are bigger, they can migrate to the ocean. After reaching adulthood, the salmon can swim upstream, through obstacles, to return to fresh water and reproduce.
Breeding this type of fish in captivity requires great care on the part of the fish farmer to avoid pests and sudden price increases. Several farms that tried to make their way onto the market using this animal turned out to be unsustainable.
We emphasize, initially, that salmon is a natural cold-water species. For that, you must keep the animal’s room temperature around 0ºC and 18ºC. In addition to this feature, this type of fish also needs a lot of oxygen. It is recommended that the salmon remain in the ponds for 12 to 18 months until they reach an average of 4.5 kilograms.
Conclusion
In this post, we answered the question “Is salmon a saltwater fish?”, we also learnt aspects of the salmon life cycle, as well as its biology and ecology.
If you have any thoughts or doubts, feel free to drop us in a comment below!
Frequently Asked Questions (FAQs): Is salmon a saltwater fish?
Which fish is salmon?
Salmon is a medium fish of the Salmonidae family, typical to European seas and rivers. Naturally found in the Atlantic and Pacific oceans, they return to freshwater at the time of breeding, often choosing the same river from which they were born.
What do salmon eat?
The Salmon diet is based on algae and single-celled organisms. These single-celled organisms are responsible for the pinkish hue of the salmon flesh.
What kind of healthy fat do we find in salmon?
The main nutrient in salmon is omega 3, a type of fat considered essential for the body and obtained only with the consumption of some foods
How is salmon spawning?
Spawning occurs in autumn and winter, when females lay between 1000 to 2000 eggs per kilogram of weight in nests dug in gravel beds, hatching occurs in the following spring.
Why do salmon live in fresh and saltwater?
Naturally found in the Atlantic and Pacific oceans, they return to freshwater at the time of breeding, often choosing the same river from which they were born. Salmon remains in freshwater for the first two or three years of life before going to sea, withstanding low temperatures in fresh or saltwater.
Why do salmon die after spawning?
Most, after spawning, die as a result of the effort, but many resist and return to swimming out to sea.
Does the salmon return to the same birthplace to spawn?
In adult life, salmon live in the oceans. During the spawning season, they are guided by the Earth’s magnetic field to “remember” the location of the region in which they were born. The fine adjustment, which guides the fish to the river or lake of origin, is via smell.
References
Webb, J. E. N. A. P. E., Verspoor, E., Aubin-Horth, N., Romakkaniemi, A., & Amiro, P. (2007). The Atlantic salmon. The Atlantic salmon: genetics, conservation and management, 17-56.
Mills, D. (1991). Ecology and management of Atlantic salmon. Springer Science & Business Media.
Asche, F., & Bjorndal, T. (2011). The economics of salmon aquaculture (Vol. 10). John Wiley & Sons.
Asche, F., & Bjorndal, T. (2011). The economics of salmon aquaculture (Vol. 10). John Wiley & Sons.
