Believe it or not, your cute little Achatina fulica is among the worlds top 100 worst pest species.
The Giant African Land Snail has been introduced to many countries, including Asia, many of the Pacific islands and the West Indies. It has also been found in the USA, but colonies of the snails have been eradicated in this country, although quarantine officials often find more GALS colonies. After introduction, its populations generally increase dramatically
The snails frequently reach such enormous numbers, at least locally, that they become not only agricultural and garden pests but also a major public nuisance, causing road hazards and making it difficult to avoid them while walking. By reaching such numbers and invading native ecosystems they also pose a serious conservation problem. Not only may they eat native plants, modifying habitat, but they probably also out-compete native snails.
GALS are major agricultural pests: due to their size and prolific breeding habits they do major damage to crops, and leave copious amounts of slime and faeces behind them. GALS is the wild, like many wild snails also carry some parasites that are communicable to humans, but there is little to fear from our pet GALS.
Many different approaches have been tried to eradicate and control Achatina fulica. Generally, none has been effective unless implemented at the first sign of infestation. Some methods are the use of chemicals such as metaldehyde or methiocarm, hand collecting, use of molluscicides, flame-throwers and also by the introduction of flatworms and predatory snails, most notably Euglandina rosea. The first attempts at such biological control were made in Hawaii. Fifteen carnivorous snail species were deliberately introduced. Of these, nine did not become established; the fate of three is unknown but they are certainly not common and do not appear to be causing serious problems. However, three have become established: Euglandina rosea, Gonaxis kibweziensis, Gonaxis quadrilateralis. There is no scientific evidence that the predatory snails are the reason for the observed decline in numbers of A.fulica. Similar ill-conceived attempts at biological control involving E.rosea in particular have been implemented in French Polynesia, American Samoa, Guam, and a number of other places in the Pacific and Indian Oceans. In addition to the deliberate introduction of predatory snails, the predatory flatworm Platydemus manokwari has also been introduced, although as yet less widely. It is reported that this flatworm can indeed cause populations of A.fulica to decline, but the evidence is only correlative, not convincingly causative. However, the flatworm has also been implicated in the decline of native species on Guam. It cannot be stressed enough that these introductions of putative biological control agents against A.fulica are extremely dangerous from the perspective of the conservation of native snail species. And in any case, there is no good evidence that they can actually control populations of A.fulica. In some regions, an effort has been made to promote use of A.fulica as food - collecting the snails for food being seen as a method of controlling them. Strict quarantine measures to prevent introduction and further spread are essential.
GALS reach new countries/areas through some of the following methods –
Agriculture: Accidental introduction alongside agricultural products (eggs and small snails).
Ignorant possession: Accidentally being smuggled aboard an aircraft or boat amongst someone’s belongings.
Landscape/fauna "improvement": Introduced deliberately as a novelty pet or as a novelty faunal addition.
Live food trade: Smuggled as a food resource.
Nursery trade: Accidental introduction alongside plants and soil (small individuals and eggs).
Road vehicles (long distance): May get attached to vehicles unobserved.
Seafreight (container/bulk): Accidentally attached to containers or their contents.
Smuggling: For use as food, medicinal use, or ornamental.
Garden escape/garden waste: Eggs and snails readily transported in garden waste.
Self-propelled (local)
Translocation of machinery (local): May get attached to machinery (e.g., road construction, landscaping) unobserved.
Please remember, check if you are allowed to keep any species of snail. You could inadvertently damage your local ecosystem. It is ILLEGAL to keeps any species of GALS in the USA.