Crayfish facts for kids
They breathe through feather-like gills. Some species are found in brooks and streams where there is running fresh water, while others thrive in swamps, ditches, and paddy fields. Most crayfish cannot tolerate polluted water, although some species such as are hardier. Crayfish feed on living animals and plants, and detritus. There are about 150 crayfish species in North America, and over 540 species worldwide.
Crayfish live in streams, rivers, swamps, ponds, and other freshwater habitats. Most crayfish are strictly aquatic but some live in semi-aquatic environments. The semi-aquatic crayfish burrow into the soil to get to water (so that they can breathe).
Crayfish are omnivores; they eat plants, animals, and decaying organisms. They are nocturnal (most active at night) and eat fish, shrimp, water plants, worms, insects, snails, and plankton. Larval crayfish are very tiny; they eat plankton.
Crayfish are eaten worldwide. Like other edible crustaceans, only a small portion of the body of a crayfish is eaten. In most prepared dishes, such as soups, bisques, only the tail portion is served. At crawfish boils or other meals where the entire body of the crayfish is presented, other portions, such as the claw meat, may be eaten.
As of 2005, Louisiana supplies 95% of the crayfish harvested in the US. In 1987, Louisiana produced 90% of the crayfish harvested in the world, 70% of which were consumed locally. In 2007, the Louisiana crawfish harvest was about 54,800 tons, almost all of it from aquaculture.
Crayfish are commonly sold and used as bait, either live or with only the tail meat, and are good at attracting channel catfish, walleye, trout, largemouth bass, smallmouth bass, pike and muskellunge. Sometimes the claws are removed so that the crayfish do not stop fish from biting the hook. Crayfish easily fall off the hook, so casting should be slow.
Crayfish are kept as pets in freshwater aquariums. They will sometimes consume their old exoskeleton after it has moulted. They are also relatively non-aggressive and can be kept safely.
Since crayfish are accustomed to being in ponds or rivers, they will have a tendency to shift gravel around on the bottom of the tank, creating mounds or trenches to emulate a burrow. Crayfish will often try to climb out of the tank, especially if an opening exists at the top that they can fit through.
Crayfish may spread into different bodies of water because specimens captured for pets in one river are often released into a different catchment. There is a potential for ecological damage when crayfish are introduced into non-native bodies of water (e.g., crayfish plague in Europe).
Crayfish have been recorded as an invasive species from Louisiana to Europe to China. They have been known to consume local rice crops in China.
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Crayfish Facts for Kids. Kiddle Encyclopedia.