Expanded knowledge: Chinese Academy of Fisheries Research Freshwater Fisheries Research Center statistics show that in 1973 the Yangtze River Basin and along the Yangtze River swordfish production of 3,750 tons in 1983, about 370 tons, and by 2002 the production of less than a hundred tons in 2010 for 80 tons in 2011, is only 12 tons. Due to engineering construction, water quality pollution, sand mining and dredging, overfishing and other factors, the production of Yangtze River swordfish showed a precipitous decline. In order to protect the aquatic biological resources in the Yangtze River Basin, the Ministry of Agriculture and Rural Development has recently issued a fishing ban. According to the circular, starting from February 1, 2019, the issuance of special fishing licenses for crabs (Yangtze River cutlass fish), crested crabs (anchovies), and Chinese mitten crabs (river crabs) will be stopped, and the productive fishing of the above three natural resources will be prohibited. After the notice was issued, the Yangtze River and along the fisheries departments have increased enforcement inspections.