Achatina fulica Bowdich,1822 Achatina fulica is a native of East Africa but has spread out over a wide region in the world.It has been widely distributed by humans throughout the world. Around the year 1800 the wife of a governor of Mauritius was suffering from chestpains.The doctor's advise was to get some Achatina snails from Madagascar.(snails have been used for a wide variety of illnesses among them those of the pulmonary kind).Unfortunatly the wife died soon and the snails were set free. In the years after that Achatina fulica slowy reached other places:the Seychelles in 1840,The Comoros in 1860,it was taken to India(Calcutta) in 1847 by Benson. Sri Lanka(then Ceylon)reported the snail in 1910,where they were released around 1900.It was seen in 1922 in Singapore, then a little later in Indonesia,China and Hong Kong in circa 1941. In 1925 people brought the snail to Japan,and although it never became established there,it did found its way to some Micronesian Islands(Rota,Ponape,Tinian,Yapa and Saipan). The United States got to know Achatina fulica first in 1936 in Hawaii.Despite efforts to deal with the snail almost immediatly it spread quickly. In 1946 or 1947 a few snails were found in San Pedro,California.These were quickly killed.Once again the same thing happened in 1959 in Mesa,Arizona.But when a boy brought some over from Hawaii to Florida in 1966 it took 7 years and about 700.000 dollars to eradicate them all. And even in recent years Achatina fulica's are found in the USA,quite often as classroom pets.Since 2003 4000 snails have been seized in Wisconsin,Illinois,Indiana,Iowa,Ohio and Pennsylvania.Interestingly none of these snails was a carrier of the parasite that can cause meningitis. Recent introductions are :Morocco(1987),Brazil(1980) and Barbados(2000). Photo: David Robinson. APHIS, NAS Achatina fulica can cause damage in different ways,either directly or indirectly.Of course they eat a wide range of plants,either agricultural or ornamental. They can also be the host of the Rat lungworm,which can cause meningoencephalitis in humans. Although the biggest risk is when the snail is eaten raw or undercooked. Indirect damage can be caused when man starts to introduce other snails(Euglandina)to try to control the Achatina population.Usually these plans backfire with disastrous effects. (see more here)
Short life history Even though Achatina fulica can reach an age of 9 years,3-5 is usually the average. They can reproduce after 6-9 months.The eggs are laid in clutches of 10-300 normally within 3 weeks of mating.They usually will hatch in 8-14 days,but temperature and humidity are,of course,a big factor.After hatching the young snails will stay under- ground for about one or two weeks,eating their eggshells.The younger snails are the ones who cause most damage to plants,once they get older the snails will eat more and more decaying materials.
More info: Global invasive species database:Achatina fulica Achatina fulica:extensive species info