Despite their apparent lifelessness, coldness and harshness, the seas of the Arctic Ocean, like the Arctic Ocean itself, are home to many living organisms. Ranging from unicellular and plankton to large mammals.
Polar cod
Not the last place in this cold land is occupied by polar cod fish (lat. Boreogadus saida), a small pelagic fish of the cod family, which is also called polar cod. This peculiar fish does not like warm waters and prefers rather low temperatures: minus or close to 0 degrees Celsius.
When the temperature of ocean and sea waters rises to +5, polar cod is usually no longer found. In summer, this cold-loving fish prefers to stay near the ice edge, mostly in the Kara or Barents Sea.
I wonder where the polar cod fish lives. It swims north of any other fish species at 85 degrees north latitude. Such low temperatures are easily tolerated, due to the presence in the body, namely in the circulatory system, of the glycoprotein AFGP, which does not allow the fish to freeze.
His actionlies in the fact that it literally envelops the ice crystals, does not allow them to grow, so that the fish does not freeze and does not turn into ice. The polar cod loves to swim not only in coastal waters, but also in the open sea, mainly under ice floes and icebergs.
Prefers the upper layers of water, slightly desalinated from melted ice floes. Saika is not a deep-sea fish and does not descend below 500-900 meters from the sea surface. It keeps in flocks and migrates, like most schooling fish, vertically: in the morning and in the evening it lies on the bottom, and during the day and at night it swims throughout the water column.
Appearance
Saika fish looks quite unremarkable, elongated thin body, brown-gray on top and silvery below, with a yellowish (sometimes purple) tint. A large head and large bulging eyes, the lower jaw is pushed forward, which gives it a comical appearance. She swims rapidly thanks to the structure of her body, which helps her to save herself from lovers to feast on her.
Podfish, long-lived fish. She has a life expectancy of 6-7 years. For northern latitudes, this is a lot. In length (it is the smallest of the cod family), adults reach 27-30 cm, some individuals can reach 40 cm, and the weight does not exceed 250 grams.
Food for northern dwellers
What does polar cod eat? The fish prefers phytoplankton, zooplankton, small crustaceans, fry of other fish. Arctic cod is an important link in the food chain of the Arctic Ocean. Being the main consumer of oceanic plankton, it serves as the main food for aquaticbirds, seals, narwhals, beluga whales, polar bears and foxes, arctic foxes, other carnivorous fish.
Sika fish washed ashore during storms serves as food for land animals. Its meat is dietary, of high nutritional value, but due to its low taste (hard and watery), polar cod has not become a popular commercial fish. But it is excellent for processing and making fishmeal, canned food in oil and tomato sauce, curing and smoking, and making animal feed.
With the onset of autumn, polar cod gather in large flocks and, moving west and south, swim up to the shores, which makes it possible to observe the accumulation of this fish in the coastal zone and in estuaries. This period, from October to March, is the spawning period for polar cod.
In the same period, she begins to eat, as the fishermen say, and her fishing goes on, although the fish itself does not have an exquisite taste. The main catch is in the Barents and White Seas.
Spawning
Spawning in polar cod occurs at temperatures below zero Celsius, but this is not critical, since her eggs are frost-resistant and floating. Mosque from 7,000 to 60,000 eggs per cod. After spawning, the fish swims back into the sea, sometimes swimming in the mouths and lower reaches of the rivers.
Its eggs drift for 3-4 months and are carried by the current quite far from the spawning site. The fry appear only in April, May, but the polar cod grows quickly, and already at the age of three reaches an average of 17 centimeters in length. Further adding 2-3 centimeters every year, it reaches its maximum by 6-7years.
Public cod fish reaches an average of four years, and spawns mostly once in a lifetime. The fry feed on small oceanic and marine plankton. With growth, the young begin to hunt fry of other fish and tiny fish.
