Pest invasion is a hot and difficult problem in today's world. Since the 60s of the 20th century, the problem of invasive alien species has become prominent and serious. The invasion of alien species not only causes huge economic losses to some countries, threatens the lives and health of their humans and animals, but also destroys biodiversity, causing the endangerment or even extinction of some native species. The report of the 20th National Congress of the Communist Party of China clearly pointed out the need to "strengthen biosecurity management and prevent and control the invasion of alien species". The African giant snail is a worldwide agricultural pest, which has a great impact and harm on the native species, ecological environment and social economy of the continent.
African giant snails from pets to pests
African giant snail, also known as brown cloud agate snail, African giant snail, vegetable snail, flower snail, etc., belongs to the mollusk phylum, gastropoda, pediophthalmopoda, agate snail, agate snail, native to eastern Africa, has been widely distributed in Asia, the Pacific, Indian Ocean and the Americas and other humid hot areas. Compared with ordinary snails, the African giant snail is larger in size, slightly thicker in shell, with an onyx-like pattern on the body and two pairs of retractable rod-like antennae, which is very cute and is regarded as a pet by many people. However, the "fall out of favor" was then discarded at will, but it became one of the ways in which the African giant snail was widely spread.
Due to its slow crawling speed, the African giant snail's ability to spread naturally on land is very limited. It is mainly transmitted through artificial means, such as the circulation of goods, artificial carrying, etc. The life span of African giant snails is relatively long, generally up to 5~7 years. It is also highly resilient, can go into hibernation when encountering adverse environments, and can survive in this state for several years. At present, the African giant snail has spread to Guangdong, Hong Kong, Yunnan, Guangxi, Fujian and Taiwan in the mainland, causing great damage to the local environment.
A large African snail the size of a pet puppy (picture from the Internet)
The harm of the African giant snail
The African giant snail is a dangerous pest of agricultural and forestry production and has the title of "pastoral killer" internationally. Its diet is heterogeneous and large, and its feeding is fierce. It can bite off various crops and flower shoots, shoots, young leaves, stem skin, petals, etc., affecting the growth and development of crops, resulting in the destruction of some vegetable gardens and orchards, resulting in great economic losses.
As an invasive organism, the African giant snail not only destroys local plants, but also excludes native indigenous species, affects local species diversity, and causes serious biological pollution. In addition, the African giant snail is an intermediate host for human and animal parasites and pathogenic bacteria, particularly in the transmission of tuberculosis and eosinophilic meningitis. In addition, it can transmit liver flukes, among others. In its feces, schistosomiasis, whipworm, hymenolescinus tapeworm, stercorous strongyloides and other parasites can also be detected, which are extremely harmful to human health.
Control of African giant snails
Strengthen quarantine: Strict quarantine is an important measure to stop the spread of African giant snails, and quarantine departments need to carefully inspect and disinfect goods, seeds, seedlings, plant products and means of transport from epidemic areas.
Chemical control: The control agents commonly used in production are mainly pyrethroid insecticides and organophosphorus, as well as worm grams, snail nets, etc. Although chemical control can effectively control the population of African giant snails, it is not recommended to give priority because of its environmental pollution and harm.
Manual control: cleaning the field, improving cultivation management, supplemented by manual control, or directly spreading with quicklime powder, this method is the most effective and direct way to control the spread of African giant snails.
Biological control: Using the predation of beneficial predators such as toads and birds to reduce the number of African giant snails. Poultry such as chickens and ducks are bred to peck at and control African giant snails.
The removal of the African giant snail (picture from the Internet)
The invasion of alien species is a worldwide ecological problem today. Since the invasion of the continent, the African giant snail has caused serious damage to biodiversity in many parts of the continent, and even threatened human health. In the face of its invasion, it is necessary to do a good job of publicity and vigilance, and once the spread of African giant snail damage is found, it will be reported to the quarantine department as soon as possible to prevent and control its spread harm.
Author: Luo Mingdan (Graduate student, College of Life Sciences, Hubei University)
Scientific checkpoint: Xu Lotian (Associate Professor, Hubei University)
Source: Guangming Network - Popular Science China