Recently, the case of "strange fish" in the Central Park of Ruzhou City, Henan Province, has attracted attention, and the word "alien species" has once again entered the public eye. As an "uninvited guest", the captive alligator finless eels appear more and more frequently in rivers and lakes in many provinces of China in recent years. "Guangdong's geographical conditions are more suitable for biological settlement and reproduction, so it is one of the areas with the most invasive alien species in China." Li Jun, a researcher of the Institute of zoology of the Guangdong Academy of Sciences, has long been engaged in the monitoring and control of invasive insects. He introduced that it is an important biological means to deal with alien invasive species and make good use of their natural enemies. There is a risk of the spread of alien species in the online pet shopping craze. After nearly a month of pumping and fishing, on the night of August 26, the alligator finches in yunchan lake of Central Park of Ruzhou city were finally captured. As a matter of fact, alligator finches, which are exotic and large in size, are not uncommon in China. According to statistics, in recent years, in addition to Henan, alligator finches have been reported in Beijing, Guangdong, Hunan, Guangxi and other places. Recently, in Fengdong Park, Dali Town, Foshan, some people photographed the appearance of a suspected alligator eel with their mobile phones. Some citizens described it as "about 1 meter long, very fierce, chasing fish to eat". At the end of May, in the campus of Sun Yat sen University, a student joined hands with the staff of the security office to catch an alligator finch eel in the lake inside the campus. How did the alligator finches, which originally lived in North America, enter China? Gu dangen, associate researcher of the Pearl River Fisheries Research Institute of the Chinese Academy of Fishery Sciences, explained that the alligator finless eel was once introduced as an ornamental fish because its special shape satisfied the curiosity of some consumers. However, due to their rapid growth, many people choose to discard them because they cannot provide enough breeding space. "The introduction of alien species generally includes natural transmission and artificial introduction, of which the latter is the main way." Li Jun said that the rapid development of international trade in recent decades has facilitated the migration of species between different countries and regions. At the same time, the rise of online shopping and the development of logistics have also created conditions for the spread of alien species, "especially under the current 'pet fever' of various types, various strange animals are sold on the Internet, many of which are alien species". The situation of biological invasion in Guangdong is grim. "Alien species and alien invasive species are two different concepts. Distinguishing them depends on whether they cause harm to the ecological environment, agricultural production and human health." Li Jun said. According to the environmental bulletin, there are more than 660 alien invasive species invading various ecosystems in China. In the list of four batches of alien invasive species in China jointly released by the Ministry of ecological environment (former Ministry of environmental protection) and the Chinese Academy of Sciences in 2003, 2010, 2014 and 2016 and the list of national key managed alien species (first batch) released by the Ministry of agriculture and rural areas (former Ministry of Agriculture) in 2012, the number of invasive species in Guangdong accounted for 76% of the country, including plants, insects, aquatic animals, microorganisms and other types. In Li Jun's view, the large number of invasive species in Guangdong is due to the frequent foreign trade in Guangdong on the one hand; On the other hand, Guangdong is located in sub - hot