What is the origin of crayfish?

Crayfish is a world-class biological invasive species, native to Central and South America and northeastern Mexico. It was introduced into Japan in 1918 as bait for bullfrogs, and then introduced into China from Japan. Now it has become an important resource of freshwater shrimp in China, widely distributed in the provinces and cities of the middle and lower reaches of the Yangtze River. In May 2013, it was rumored that crayfish was introduced into China by Japanese biochemical troops invading China to dispose of dead bodies.

Crayfish is a kind of crustacean like lobster that lives in fresh water, the scientific name is Procambarus clarkii, also known as red crayfish, freshwater crayfish, fighting shrimp. Crayfish is the most widely distributed alien invasive species in crustaceans. Crayfish has an absolute competitive advantage in the local ecological environment because of its omnivorous, fast growth and strong adaptability. The range of food intake includes aquatic plants, algae, aquatic insects, animal carcasses, etc., and kill each other when food is scarce.

Crayfish was introduced into China from Japan during World War II and began to breed in Nanjing City and suburban counties of Jiangsu Province. after a long period of expansion, the population number and living space continued to expand. at present, crayfish has expanded to Anhui, Shanghai, Jiangsu, Hong Kong, Taiwan and other places, forming a large number of natural populations and becoming an important resource of freshwater shrimp in China.