Crayfish are belong to the phylum Arthropoda. Crayfish lives in fresh clean water – rivers, streams and lakes. In the afternoon, crayfish hide under rocks or in burrows dug at the bottom or off the coast under the roots of trees. At night, they crawl out of their hiding places in search of food. River crayfish are omnivorous.
They feed on plants and animals, and can eat both live and dead prey. The smell of food crayfish is felt at a great distance, especially if the corpses of frogs, fish and other animals began to decay.
Crayfish, like all arthropods, has a hard cover, the basis of which is made up of organic matter – chitin. This light, but hard chitinous cover protects the soft parts of the animal’s body. In addition, it serves as an external skeleton, since muscles are attached to it from the inside. The hard cover of the crayfish is greenish-brown in color.
This protective paint makes it invisible against the background of the dark bottom. The coloring substances of the covers when cooking the crayfish are destroyed and change their color – the crayfish turns red.