Whitefish commercial fish is valued for its great taste and high nutritional qualities. Fish is a representative of salmon and is found in the cold waters of all the northern countries of the world. Whitefish lives in water bodies of Canada, Alaska, Northern Europe and Siberia, where the climate, water and food are completely different, hence a large number of subspecies of fish. Especially numerous and diverse is the fish of the whitefish family in Russia.
Despite belonging to a single biological species, whitefish are separated according to their lifestyle and morphological characteristics. Even inside one pond, fish may have differences in appearance, size, nutrition, development, taste of meat.
In Russia, whitefish is widely distributed both in the European part and in Siberia. It lives in almost all rivers flowing into the Arctic Ocean, and in Lake Baikal. On European territory, whitefish is found in Onega, Ladoga, Peipsi lakes, Curonian and Finnish bays. Especially a lot of this fish in the Karelian reservoirs.
There are whitefish, lake , migratory whitefish . Lakes and rivers are found and spawning only in lakes and rivers. Passers-by live most often in lakes, and go to rivers to spawn. Some representatives of migratory whitefish can live in salt water. They live in the sea, usually in the places where rivers flow into it, where there is a lot of food, and the water is not too salty, and spawn rises up the rivers. The juvenile migratory fish that were born live in the river for a year.
Sigi differ in the number of stamens on the branchial arch, which is located near the mouth. There are three varieties: low stamen, middle stamen, multi stamen whitefish.
There are three types of mouth position in whitefish: the upper mouth is directed upward, the final mouth is forward, and the lower mouth is downward. Different subspecies differ in body contours. In some it is smooth and streamlined, in others it is angular, in others it has a hump or a swollen chest.
Due to morphological features in the diet of whitefish belonging to different subspecies, there are differences. For example, a fish of the whitefish genus with a small number of gill stamens cannot feed on plankton due to the inability to filter it, therefore it prefers bottom invertebrates. Multi-sturgeon whitefish eat mainly plankton.
Fish, whose mouth is directed upward, usually small, feed on small organisms that live in the upper water layers. Sigi, whose mouth is directed forward, are larger, feed on crayfish, juveniles, fish roe, insects, and larvae.
The weight of the smallest whitefish does not reach a hundred grams, and the largest can weigh more than eight kilograms. Depending on the variety, whitefish does not grow equally. There are fast-growing and slow-growing forms. The subspecies of whitefish differ in number. There are varieties whose populations are very numerous, while others, on the contrary, are on the verge of extinction and are protected by law.
Whitefish is endowed with a silvery (in females yellowish) uniform color, toothless mouth, flat sides, rather large scales, white meat. Whitefish does not change color before the start of spawning; only in males does a “pearl” scattering appear on the body. In males, unlike females, a longer body and small scales.
Most whitefish subspecies spawn in cold water in late autumn. At the end of summer, before spawning begins, whitefish rises up a fairly long distance up the river. It reaches the spawning site in a few months. Typically, these sections of the river have a weak current, shallow depth and sandy bottom. After spawning, whitefish does not die, as happens in salmon, but returns to its permanent habitat.
Due to its delicious meat and high fat content, whitefish is a valuable food product. Fish contains beneficial amino acids and minerals: iodine, fluorine, zinc, chromium, iron, phosphorus. Fat whitefish is well digested and absorbed by the body, does not harm the stomach, is rich in vitamins A, D, and PP important for humans.