General Information

Giant African snail
Scientific name: Achatina fulica
Stylommatophora:Helicidae

Hosts

The adult has a voracious appetite and attacks over 500 different kinds of plants preferring, however, brassicas, lettuce, potato, onions, sunflowers, Eucalyptus, banana, and the bark and fruits of citrus

Distribution

The Giant African snail originates from Eastern Africa and is now found in the other parts of the tropics and subtropics

Damage

Snails feed on seedlings, soft plant parts, ripening fruit that are close to the soil, and organic matter. Their feeding damage is irregular large holes on leaves but they can consume the young seedlings completely.

Description

The eggs are spherical in shape, translucent, and about 4.5-5.5 mm in diameter. These are yellow to cream in color. They are laid in moist soil at a depth of about 2.5 cm and will hatch in about 14-30 days depending on the weather conditions.

The adult giant African snail has a rounded-conical-shaped shell, about twice as high as its width. It is brown in color with irregular darker streaks running transversely across its whorls (Cowie, 2004). When fully mature, its shell has 7-9 whorls (U Mass Extension, 2004). An adult can reach a length of up to 30 cm but is more common in the size range of 5 -10 cm. It has an average lifespan of 5-6 years but can survive for as long as 9 years. It can hibernate for months during unfavorable conditions.

Snails are hermaphrodites, having both male and the female reproductive organs. They have to mate to reproduce but cases of self-fertilization are reported to occur. Snails are nocturnal and come out to feed at nighttime. They are very active when the soil is wet. When the temperature is unfavorable, they can hibernate for months in the soil and become active again when the rainy season comes.

The Giant African snail is one of the carriers of the rat parasite (Angiostrongylus cantonensis) that causes meningitis in humans. An infected rat passes immature forms of the worm in its feces. A snail gets infected by eating infected rat feces. The young forms of the parasite continue to grow in the snail's body but they do not become adults. The lifecycle of the parasites is completed when a rat eats an infected snail or slug and they become adults inside the rat's body (DPD, 2004). These parasites can be contracted by eating improperly cooked snail meat or by the improper handling of live snails.