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Kamchatka crab is a migrating delicacy

Kamchatka crab belongs to the type of arthropods, a subtype of crustaceans, a kind of craboid. Outwardly similar to a real crab, and by systematics closer to hermit crabs. Inhabits the Japanese, Bering and Okhotsk Seas. Can migrate to the Barents Sea.

Kamchatka crab is the most impressive in size among crustaceans. The main parts of the body are the cephalothorax, covered with a shell, and the abdomen (abdomen). Female differs from male by more developed abdomen. He does not have a tail. The inner skeleton is also absent, its role is performed by the shell, further protecting from enemies.

Gills are located under the shell on the sides, the heart - in the back, the stomach - in the head. In the shell over the stomach there are 11 large thorns, and above the heart only 6. The crab can clearly see 4 pairs of legs, and the fifth pair is hidden under the shell. It serves not to move, but to clean the gills. On the front pair of legs the claws are most developed. The crab uses the right claw to break shells of mollusks and shells of sea urchins, and the left one for cutting sea worms.

Kamchatka crab has a dark red with a violet hue of shell, for which it is called red. The inner side of the shell is yellowish-white. The weight of a large male can reach 7 kg, the width of the shell is 28 cm, the range of the middle legs is 1.5 m. They can survive till 20 years if they are not caught and eaten. Enemies are people, octopuses, bulls, cod, sea otter, etc.

Kamchatka crabs pass along the same route every year, migrate. Winter they spend at a depth of about 250 m, and in the spring they move to shallow water to shed and multiply. In autumn they go back to the deep water. The change in water temperature serves as a signal for movement. Crabs do not move alone, many, thousands, hundreds of thousands of them move. And large males keep separate from young and females. For a year, crabs are wound up to 100 kilometers along the seabed.

Adult crab molts once a year. Moulting lasts 3 days, in these days males hide under stones, burrow into pits. Together with the shell they have an intestine, esophagus, stomach walls, tendons.

After changing the shell, the female releases caviar (eggs may be from 20,000 to 445,000) under the abdomen. She bore her 11.5 months. Next year, moving in shallow water, the larvae leave the eggs, and the females continue to move. The female lays eggs once a year, and the male can mate with several females during the breeding season.

Kamchatka crabs grow late, females reach maturity at 8 years, and males reach 10 years. Their ritual of courtship is unusual. Clinging to each other, they can stand for 3-7 days. The female helps the male in the process of molting, then mating takes place.

Larvae survive a little, about 4%. First time, the larva swims in the water, and moves by jaw motion. Then settles on the bottom, upholstered in algae. Only to three years she leaves her habitat, having had time to pour a few times. Migrate begins in 5-7 years.

The Kamchatka crab is an object of profitable fishing, but recently limited due to the reduced number of crabs. Meat of the king crab is a valuable dietary product, a delicacy containing vitamins A, PP, C, group B and trace elements. The most valuable is the right claw. Shells and insides also come into play, of which an excellent fertilizer is made.

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