The original infestation in the 1960s was from a released pet. The current infestation, detected in 2011, was from snails intended for use in religious rituals.
The giant African snail can grow to be the world’s largest terrestrial mollusk. Its shell can reach more than eight inches in length. The shell is cone-shaped with distinctive cream- and chocolate-colored stripes running across the whorls. Eggs are yellow- to cream-colored, about one quarter inch in diameter.
Giant African snails have a voracious appetite, consuming over 500 different types of plants. They rapidly devour fruits, vegetables, and ornamental plants, wiping out small farms overnight and leaving only foul-smelling excrement in their wake. Starting at about age six months, they lay an average of 100 eggs per month for the next eight to ten years.
In places where the snails do not have enough calcium in the environment to build their shells, they have been known to eat the stucco off houses and the paint off cars! When crossing roads at night, adult snails are a hazard to drivers because their large, hard shells can puncture tires. The snails are also considered a public health threat, as their slime is home to the parasitic rat lungworm (Angiostrongylus sp.) which can cause meningitis.
Giant African snails are currently only found in the greater Miami metropolitan area, and one residential area in Broward County. They are most active on humid and rainy days, and just after dusk. They seek out fruits, vegetables, and pet food that are left outside overnight. During the day, they roost on the sides of buildings near air-conditioners or hoses, or burrow into loose topsoil. They lay their eggs in humid areas with rotting detritus in the top two to six inches of soil. Young snails may live underground for the first two to six months of their lives.