Chinese mitten crab (mitten) (lat. Eriocheir sinensis) belongs to the family Varunidae. First discovered in the waters of the Yellow Sea. The name was given due to the feature numerous villi on walking paws.
Description
This is one of the few crabs that can stay out of the water for a long time. Thanks to this feature, Chinese shaggy-armed arthropods easily move between watersheds, getting into a new reservoir. But they make these trips exclusively at night and with the presence of dew.
This is an excellent indicator for the animal, as the risk of extinction of the species is excluded. On the other hand, all other living beings suffer. The reason for this is too sharp teeth and strong claws, as well as the need to build burrows. Moreover, shelters are built individually, and the number of these crabs is so large that night crossings lead to destruction.
What is destroyed:
Many people do not understand how such a small crab is capable of destroying, for example, a dam. It’s all about density. Their parameters vary from 25 to 55 cm, and sometimes more. At the same time, for 1 sq. m can be located about 30 crab holes. If we take into account that they move in thousands, then we can estimate the damage caused.
For this, the mitten crab is called an ecological bully. They carry another danger: they are carriers of infections transmitted to humans.
Algae, remains of mollusks and fish are used as food.
Appearance
The hairs on the claws in appearance resemble shaggy armlets. This is the most distinctive touch in the Chinese mitten crab. But there are other indicators that you should pay attention to:
Otherwise, the shaggy-armed representative of the fauna is visually no different from other crabs.
Structure
The structure of the mitten crab has its own characteristics:
The hair on the claws is shorter in females than in males.
Where do they live
This species was brought to Europe only at the beginning of the 20th century, so now they live not only in China, but throughout the world. In the Black Sea, it was discovered only in 2002, then it was found in Lake Onega, on the Volga and various reservoirs. This distribution has an explanation mitten crabs easily adapt to both salt and fresh water.
Optimal conditions:
reproduction
To mate and hatch eggs, crabs move to salty waters. Sexual maturity occurs at 2 or 3 years in the southern regions and 4 or 5 more northern. Migration is characterized by a long period from July to November (in one day the crab moves up to 10-12 km).
Breeding process:
After the larvae emerge from the eggs, the female dies.
Chinese mitten crab is considered a delicacy in its homeland. In other countries, it is rarely used in cooking, since there is practically no meat in it. Life expectancy is short only 5-6 years.
