Crayfish are crustaceans belonging to the Astacoidea superfamily. They do not have an internal skeleton, but are encased in an exoskeleton that protects the body. The first part comprises the head with a pair of antennae. The second includes the thorax with three pairs of 'jaw-legs' and two additional pairs of legs by which crayfish move. The third part consists of the abdomen, ending in the tail.
Crayfish are generally more active at night, devouring almost everything in their path, from molluscs to fish eggs, insects and younger members of their own species. They can reach 200 g in weight, with a maximum length of 20 cm.
Mating periods, spawning and incubation times vary depending on the species of crayfish, but the mating process is similar. Depending on the species, age and size, female crayfish each lay between 50 and 600 eggs, which evolve into embryos and then into larvae that cling to the abdomen of the female for a few days.
Crayfish have many predators, mostly fish such as trout, perch, pike or monkfish. They also serve as prey for some birds, such as herons and ducks, and also for mammals, such as otters, musk rats, and... human beings. Moreover, some species (including native species of Western Europe) are more susceptible to viruses, fungi and other parasitic worms.
Of the over 470 species of crayfish found around the world, only three are native species in Western Europe. There are very few restrictions on fishing, and consumption of American species is strongly encouraged.
Once in the kitchen, crayfish can be prepared like shrimp, with garlic, parsley, shallots, and broth, or dipped in mayonnaise, to accompany lemon rice for example.