Crayfish is a world-class biological invasive species, native to Central and South America and northeastern Mexico. It was introduced to Japan in 1918 as bait for raising bullfrogs. , and then introduced to China from Japan, it has become an important freshwater shrimp resource in my country and is widely distributed in the provinces and cities in the middle and lower reaches of the Yangtze River. In May 2013, it was rumored on the Internet that crayfish were introduced to China by the biological and chemical troops of the Japanese invaders and used to dispose of corpses. This statement is purely a rumor.

Crayfish is a lobster-like crustacean that lives in fresh water. Its scientific name is Procambarus clarkii. It is also called red crayfish, freshwater crayfish, and fighting shrimp. Crayfish are the most widely distributed alien invasive species among crustaceans. Crayfish have an absolute competitive advantage in the local ecological environment due to their omnivorous nature, fast growth rate, and strong adaptability. Their feeding range includes aquatic plants, algae, aquatic insects, animal carcasses, etc. They will also kill each other when food is scarce.

What is the origin of crayfish?

During World War II, crayfish were introduced to China from Japan and began to multiply in Nanjing City and suburban counties of Jiangsu Province. After a long period of expansion, the population size has continued to increase and the living space has continued to expand. At present, crayfish have expanded to Anhui, Shanghai, Jiangsu, Hong Kong, Taiwan and other places, forming a large natural population and becoming an important resource among freshwater shrimps in my country. .