Learn all about the main characteristics of this interesting and delicious fish called salmon, and find out why this is one of the favorite species of many internationally renowned chefs.
Salmon are marine and freshwater fish belonging to the Salmonidae family (ray-finned fish). The term salmon comes from the Latin word salmo which in turn might have originated from salire which means jumping. There are nine commercially important species of salmon, distributed in two genera.
The genus Salmo contains the Atlantic salmon, which is distributed in the North Atlantic, as well as many species commonly called trouts . On the other hand, the genus Oncorhynchus contains eight species that only inhabit in the North Pacific Ocean.
Table Of Content
Taxonomy 🐟
Phylum: Chordata Subphylum: Vertebrata Class: Actinopterygii Order: Salmoniformes Family: Salmonidae Genre: Salmo
Salmon: Main Characteristics 🐟
Salmon are pink in color and have spots on their fins and back. The adult specimens have a long and slender body, and usually females are larger than males. This species and the trout are similar in appearance. Their body´s color is the only difference between them and even both have a small fin on their back called adipose fin, being the only species of fish that possess it.
Salmon or sea tigers (as are also known), have eight fins, the caudal being the largest, and the one that fulfills the main function in terms of displacement. Their tail is quite flexible and powerful, which allows them to travel twenty thousand miles in the ocean, and achieve speeds of up to 50 kilometers per hour.
They can even jump more than four meters to climb waterfalls and obstacles in the water. These interesting and very tasty fish also have medium fins located in their back and belly, called dorsal and pelvic fins which prevent them from tipping or rolling. The pair of pelvic fins are located in their belly, while the pair of pectoral fins in their lower part, very close to the head. Both sets of fins serve to prevent them from falling forward.
Salmon are silver fish while in the ocean, but during the breeding season there is a change in coloration that varies from one species to another. In terms of length and weight it should be noted that they can reach 150 cm of total length and up to 45 kilograms of weight.
Other traits 🐟
Salmon are usually anadromous, which means that they are born in freshwater, then migrate to the ocean, to finally return to the fresh water when it comes time to reproduce. However, there are also species that are limited to freshwater throughout their lives.
Young specimens remain in freshwater from 2 to 3 years to migrate to the sea and return after 2 years to carry out their reproductive cycle. Some salmon can reproduce up to 4 times.
Let´s meet them
How Salmon Reproduce? 🐟
Salmon are born in freshwater rivers. Normally, it´s in autumn when the female and the male place the eggs in the rivers to fertilize them in a nest built with gravel. After a few months of incubation, the eggs hatch and the juvenile salmon are born. They remain for a few weeks in the gravel where they acquire some swimming skills.
When spring comes the rise in temperatures favors the juvenile learning, which leave from the gravel and start their independent life. There are many experts who study the salmon’s life cycle, above all, this phase of their life, as they try to explain how salmons know that they have to return to their mother river to spawn.
Life 🐟
When juveniles are larger and more independent, they begin to swim along the river to the sea. Once there, they continue swimming and roaming the seas for varying periods depending on each species.
Once the time has passed and as adults, salmon try to return to their birthing place to spawn and reproduce. This return trip is quite complicated as they have to swim counter-current and unfortunately not all salmon survive. The road to their birthing river is full of difficulties and dangers.
Back to Their Birthing River 🐟
When they reach the mouth of their birthing river they begin to climb in a group if the waters aren´t very turbulent, and in the case of a very plentiful river some species do it in a row.
During the ascent of the river they have to go around the water swirls, the largest rocks, bears and other predators, the trees in the middle of the river, the pollution by containers and plastics, and all this against the current. All these obstacles cause a bad state in their bodies that make their appearance deteriorate compared to when they used to live in the seas.
Reproduction 🐟
Once they go up the river, salmons swim directly to the spawning area where they were born, remaining there until they reach sexual maturity and then spawn.
Once sexually prepared to reproduce, the female swims near the bottom of the rivers to build the nest of gravels where the eggs will be placed. While the female builds the nest, the male moves away the other males who are attracted to the female.
The female agitates and moves her tail to build a nest of around 40 or 50 centimeters. This construction takes a few hours, while the female chooses and joins the more apt stones for the “cradle» where the new salmon will be born. In addition, they can build up to five nests while checking the quality and depth of them.
Once the nests are built, the female allows the male to stand next to her to release the eggs, while the male does the same with his sperm. In this way fertilization takes place.
When the water clarifies as a result of the seminal fluid, the female cover the eggs while moving the tail like a fan without touching any stone.
In this way she creates a current that moves the eggs into the gravel to avoid any damage for them.
As the action ends in a nest she builds the next one. In each one she deposits between 500 and 1000 eggs. During the days later she covers them to protect them until she dies. It´s very important that this last phase goes well for the new juvenile to grow.
That’s why the rivers pollution and alteration by human beings, are factors that make it very difficult for salmon to reproduce.
As mentioned before, scientists look for reasons why salmon only spawn in their maternal river and not elsewhere.
However, no clear explanation has been found so far. It is thought that they have receptors in their nervous system which record and keep the environmental conditions in which they lived, to use them later as sort of guiding-map.
Let´s watch and learn
What do Salmon Feed On? 🐟
Salmon fish feed on terrestrial and aquatic insects, zooplankton, amphipods, crustaceans, and other invertebrates during their juvenile stage. When they are adults, they feed mainly on tetra fish, but they can also eat squid , shrimps, and eels, among others.
When salmon are grown on specialized farms, they are fed with concentrates and proteins, (mainly live food) that are carefully pre-selected. Sometimes they are provided with a vegetarian diet, and other supplements, although the specimens that are fed in this way usually lack omega-3.
Cultivation of Salmon 🐟
Salmon cultivation began at an experimental level in 1960s, but became an industry in Norway in the 1980s and in Chile the 1990s. The cultivated salmon industry has grown substantially in the last 40 years and today around 60% of the salmon consumed in the world is cultivated. In 2018, more than 5 200 000 tons of farmed salmon were produced while, in contrast, about 160 000 tons of wild salmon were caught.
As for, the cultivation of Atlantic salmon, it is mainly concentrated in a small number of regions (Chile, Norway, Canada and Scotland) that have the proper natural conditions for salmon’ farming. These conditions include: low water temperatures that vary between 8 ° C and 14 ° C (46 ° F and 57 ° F), a protected coastal area and optimal biological conditions. However, in countries such as Australia, the Faroe Islands, Iceland, Ireland and New Zealand, this activity has started with good results.
The production cycle of salmon farming lasts about three years. The first one occurs in controlled freshwater environments and then the farmed salmon is transported to cages in seawater. Once the farmed salmon reach a harvestable size, they are transported to processing plants and prepared for sale. For consumers, most of the farmed salmon is sold as fillets, although you can also buy the whole fish.
Let´s watch and learn
Why Do We Need Salmon Aquaculture? 🐟
The FAO (United Nations Food and Agriculture Organization), predicts that the world population will reach 9700 million by the year 2050 and it´s expected that the need of proteins will grow by 40% worldwide. The United Nations, however, estimates that actual demand will double.
Fish, (particularly farmed salmon), can offer a solution to satisfy this increased demand. As demand grows, there will be undoubtedly and increased pressure on already overexploited fish stocks, which is why farmed fish are required to manage and effectively maintain both: wild fish stocks and the ocean’s natural biodiversity .
It’s important that the farmed salmon industry ensures that sustainability is at the heart of its operations if it will satisfy this demand in a sustainable manner.
In addition to humans growing populations, the demand for fish is increasing as governments, and food and health advisory councils are actively encouraging people to consume more fish as part of a healthy and balanced diet.
Farmed salmon is commonly recognized for its high omega-3 content, but it´s also a good source of high quality protein, vitamins and minerals, so it´s often a healthy food choice for many consumers.
The farmed salmon is also a highly efficient source of protein production and continues to outperform other protein producing sectors (chicken, beef, pork) when it comes to key data such as feed conversion factors, (food necessary for an animal to gain a pound of body weight) protein retention and carbon footprint.
So, it’s clear that the salmon farming industry can make a key contribution for the growing global population feeding needs, as well as satisfying the demand for production.
Habitat and Distribution 🐟
Salmon can live both in the ocean, in brackish waters, and in fresh water, so that both streams and estuaries are an important part of many species of salmon fish. Estuaries and their associated wetlands provide vital breeding areas for salmon before their departure to the open sea. Moreover, wetlands not only help dampen the estuary from sediment and contaminants, but also provide important areas for salmon feeding and protection.
Salmon Distribution 🐟
Atlantic salmon breed in northern rivers on both coasts of the Atlantic Ocean.
The Chinook salmon is also known in the United States as King salmon, or black salmon and is the largest of all the Pacific Ocean salmon, (weighs more than 14 kilograms). This species extends to the north reaching the central Canadian Arctic and to the south to the central California coast.
Chum salmon or calico salmon, as it is known in several areas of the United States, is widely distributed in the Pacific Ocean. The Sacramento River in California, the Sea of Japan, the western Pacific North, and the Lena River in Siberia are some of the many sites where you can find this species.
Coho Salmon, also known as Silver Salmon, is located along the coastal waters of Alaska and British Columbia, and extends south to Monterrey Bay in California.
Masu salmon is found only in the western Pacific Ocean in Japan, Korea, and Russia.
The pink salmon, better known as Humps, is located in northern California and Korea, throughout the North Pacific, and from the Mackenzie River to the Lena River in Siberia.
Let´s watch them
The Red Salmon (Sockeye salmon) is located south of the Klamath River in California, in the eastern Pacific Ocean, north of the island of Hokkaido in Japan, in the western Pacific at the entrance of Bathurst in the Canadian Arctic in the east; and in the Anadyr River of Siberia, in the West.
Although most of the Pacific adult salmon feeds on small fish, shrimp and glass squid, the red salmon feed by filtering their food through the gill branches.
Salmon as Food 🐟
The salmon meat is typically pink, although their color ranges from red to orange. The king salmon and the red salmon are greasier than the pink and the chum, while the Coho is in the middle of the fat scale. The king is the largest and the red the smallest.
The Nutritional Benefits of Salmon 🐟
Fish and seafood are full of nutrients and salmon is not the exception. In fact it´s an excellent source of high-quality protein, vitamins and minerals like the potassium, selenium and vitamin B12.
However, it’ s their omega-3 acids content which receives more attention.
100 grams of salmon contain…
- 231 calories
- 25 grams of protein
- 3.2 grams of saturated fat
- 85 milligrams of cholesterol
What science says 🐟
The most beneficial omega-3 fats are those found in fatty or blue fish–such as tuna , cod, anchovies, and salmon—which contribute to keep the brain, heart and joints healthy, and help the general well-being. In addition to all these benefits, scientists now argue that fish consumption can reduce the risk of several cancers, as well as many chronic diseases such as Alzheimer’s, asthma, depression, 
diabetes, high blood pressure, macular degeneration, sclerosis Multiple and rheumatoid arthritis.
The Omega-3 is called an essential fatty acid since the human body isn’t able to synthesize it and must get it from the diet. So, it´s ideal to eat fatty or blue fish at least three times a week.
When it comes to buying and keeping 🐟
Salmon can be bought as fillet, fresh, frozen, canned or smoked. The fresh should have soft, moist skin. If it is whole, its eyes must be bright and clear, not cloudy or sunken. If you can’t eat it in the next two days after buying it, it’s best to freeze it. But once it freezes and thaws, it should not be re-frozen.
Risks 🐟
Fish farming produces most quantities of the salmon consumed. Natural salmon is superior in several respects because it contains less pesticide residues. However, no study has shown that eating fish from hatcheries is a health risk. Smoked salmon is considered a safe food even during pregnancy.
It also worth mentioning that in conjuntion with the Palometa, anchovies, catfish, clam, crayfish, oysters, sardines, shrimp, squid, tilapia, hake, pollock, scallop, trout, are the fish with less mercury content. We invite you to read our article bonito fish to learn about methyl mercure in fish
This information should not be taken as an alternative to the medical consultation. In any health-related aspect, you have to follow the instructions of a specialist. Follow the same safety rules as with raw meat or chicken: Make sure you cook it well by measuring the thickest point and cook for 10 minutes per 25 millimeters thick. The meat of a well-cooked salmon is firm but juicy, and easily melts.
bon appétit