Miami Battling Invasion of Giant African Snails

Giant African land snails are shown to the media as the Florida Department of Agriculture and Consumer Services announces it has positively identified a population of the invasive species in Miami-Dade county, last September. The Giant African land snail is considered one of the most damaging snails in the world because they consume at least 500 different types of plants.

No one knows how they got there. But an invasion of African giant snails has southern Florida in a panic over potential crop damage, disease and general yuckiness surrounding the slimy gastropods.

The US and Florida departments of agriculture have mobilized 34 agents to battle the infestation and the US Fish & Wildlife Service is heading up an investigation into how the mollusks -- which can be up to 20 centimeters (eight inches) long -- arrived.

The lissachatina fulica, or giant African land snail, can live up to nine years, and are prolific in reproduction, laying up to 1,200 eggs a year, making it extremely invasive. A single snail can create a mass that invades an entire neighborhood.

Local resident Yolando Garcia Burgos one morning discovered snail excrement on her exterior wall, and ended up collecting 583 of the mollusks in a week, finding them in her bushes, on her grill and in her ivy. State authorities say they have captured 35,000 since the invasion began in September.

The snail can lay up to 1,200 eggs a year and feasts on some 500 plant varieties. The pest is also a threat to agriculture, feasting on some 500 plant varieties including peanuts and melons. It's not clear how the world's largest snail species arrived in Florida. Originally from east Africa, they have also been found in Caribbean islands including Guadeloupe and Martinique.

This is not the first invasion for Florida. In 1966, a boy imported three giant snails as pets, and his grandmother released them into the wild, which led to a colony of 18,000. The eradication effort took nine years and cost over one million dollars.

Importation of these animals is illegal in the United States without a federal permit. But officials point out they are used in certain Afro-Caribbean religious practices.

Fagan says it's not clear if the snails were brought over for religious ceremonies or as pets and got "out of control."

The eradication effort is in full force even though the snails are in a sort of hibernation during which they dig themselves into the ground, making them less visible.

Authorities are hoping to bring down the population before the spring rains, which could cause a population surge.

Officials say the areas being cleaned up will remain under scrutiny for several months. Gardens are treated with iron phosphate, which are not harmful to other animals, but disrupt the snails' feeding habits.

The captured gastropods are taken to a lab where specialists like Mary Yong examine them and, ultimately, kill them off. The snails are effectively drowned in an alcohol solution. Or scientists toss them in the freezer to ensure they are dead.