By Sam Wasson
Updated Oct 28, 2022
It sounds like the introduction to a horror movie, “Giant snails terrorize Floridians, destroying homes, crops, and carrying a dangerous parasite.” But, this was a nightmarish reality for Florida in the 1960s and as recent as the summer of 2022. The giant African land snail (GALS) has been a recurring problem for the Sunshine State, one that continues to slowly stir up trouble to this day.
Also known as giant African snails (GAS) or Lissachatina fulica, they originated in East Africa and were prominent in Asia before being introduced to the U.S. via Hawaii in 1936. This massive mollusk later found its way to the U.S. mainland through Florida in 1966, spreading like a slow-moving, slimy wildfire. It took Florida 10 years and $1 million to eradicate this invasive snail, but it was unfortunately reintroduced in 2011, 2021, and 2022. After each infestation, Florida officials effectively eradicated this damaging pest, only for the illegal pet trade and accidental stowaways to bring them back again.
GAS are some of the biggest snails in the world, taking the top spot as the largest land species. They can grow up to 8 inches in length and are typically about the size of an adult human’s fist. They have a long, curled, pointed shell with brown, striped coloration. Their skin color ranges from light tan to yellow, brown, and red. They have two eyestalks and a set of face tentacles.
Giant African land snails are considered one of the most invasive pest species in the world. They’re most commonly found in Africa, Asia, the Caribbean, South America, and occasionally North America. This voracious mollusk eats over 500 different types of plants and certain housing materials containing calcium, like paint or stucco. These snails prefer peanuts, beans, peas, and melons but won’t shy away from taking a bite out of decorative plants and tree bark.
Like most gastropods, this snail is naturally hermaphroditic, each possessing a set of male and female reproductive organs. As a result, every snail can lay between 100 to 500 eggs every few months, producing up to 1,200 eggs per year. While these snails prefer tropical environments, as they need both heat and moisture to thrive, they’re hardy creatures possessing the ability to survive in multiple habitats. During colder months, they can enter a state of semi-hibernation until the end of winter, and if faced with a drought, they can enter a state of aestivation.
Along with destroying ecosystems, these snails pose a significant health risk to humans. They can carry several dangerous diseases like salmonella, bacteria, and the rat lungworm parasite. Rat lungworm (or by its scientific name Angiostrongylus cantonensis) is a parasitic worm (nematode) found in rats, slugs, snails, and occasionally, shellfish. While infections are rare, if exposed to snails carrying this parasite, you can become infected with them, resulting in a rare form of meningitis.
Due to its highly destructive nature, risk to human health, rapid reproduction, and difficulty of removal, it’s currently illegal to own this snail as a pet in all 50 states. Furthermore, it’s illegal to import them for any reason without a permit.
As of writing this article, the quarantine of Pasco County, Florida, is still ongoing. According to the Florida Department of Agriculture and Consumer Services (FDACS), over 4,000 snails have been collected since the first sighting in June 2022. The current eradication efforts have been in place since June 24, then resumed in August, centered around the New Port Richey area of Pasco County. The efforts put forth by the FDACS’s Division of Plant Industry include surveying, treatment with metaldehyde snail bait, capturing, quarantine, and public outreach.
If you’re within the quarantine area, which can be found on the FDACS website, it’s illegal to do the following:
If you’re in Florida and come across an African Land Snail, don’t attempt to handle it, as it can pose a serious health risk. Instead, you should contact the FDAC hotline at 1-888-397-1517. They may ask you to send a photo and location information upon reporting.
Since its introduction to the United States in the 1900s, this snail has been a consistent headache for state and wildlife officials. While some photos of this dangerous arthropod have been trending online, agencies like the FDACS and the United States Department of Agriculture (USDA) have reinforced that these snails are pests, not pets. In her interview with CNN, Christina Chitty, a public information director at FDACS, believed that most outbreaks result from exotic pet owners illegally importing these snails, then releasing them into the wild. Florida has seen several other invasive animal species spread throughout the state due to negligent pet owners, including the Burmese python and lionfish. Like all invasive species, these mollusks pose a serious risk to Florida’s ecosystem and, potentially, the ecosystems of surrounding states.
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