Giant Snails Take Over Part of Florida—Again

Officials issued a quarantine to control the invasive species, which devours vegetation, damages structures and can carry a parasite dangerous to humans

A giant snail on a gloved hand outside
A giant African land snail Pest and Diseases Image Library, under CC BY-NC 3.0 US (cropped)

Editor’s Note, June 21, 2023: The invasive, eight-inch-long snails that have plagued Florida in the past are back in the state—and to control them, officials have issued a quarantine, according to USA Today’s Mary Walrath-Holdridge. As a result, people in a 3.5-square-mile area of Florida’s Broward County are prohibited from moving the giant African land snails, and they also must not transport certain plants, soil, compost and yard debris that could contain snails or their eggs. The Florida Department of Agriculture and Consumer Services will treat affected sites with metaldehyde, a pesticide that blocks the snails from producing mucus. Without their slime, the snails become dehydrated and die within days. Below is our story from last year, when the snail population exploded in a different Florida county.

The invasive giant African land snail—one of the most damaging snails in the world—has returned to Florida for the third time in the state’s history, according to the Florida Department of Agriculture and Consumer Services. Since their latest discovery in June, and as of late last week. officials had captured 1,434 dead and alive snails on 30 properties in Pasco County, about 40 minutes northwest of Tampa, reports CBS42's Sam Sachs. 

The giant African land snail has a voracious appetite, eating over 500 types of plants and sometimes even consuming plaster and stucco, putting structures at risk. The snails can produce 1,200 eggs in a year and grow up to about the size of a human fist.

They can also carry rat lungworm, which causes meningitis in humans. 

“If you see one of these snails, do not touch it,”  Florida Agriculture Commissioner Nikki Fried said at a news briefing earlier this month. “Most importantly, do not eat them. This is not a snail to be put on butter and oil and garlic.”

A brown dog wearing a vest that says "FDACS K-9"
Sierra, a chocolate lab, was one of two specially trained dogs that help sniffed out giant snails during the last outbreak in 2015 in Miami, Florida. Kerry Sheridan / AFP via Getty Images

The snails were first found in the state in the 1960s, and it took $1 million and about seven years to get rid of them. In 2010, they were reintroduced and eradicated after a decade and $23 million. It’s unclear how the snails arrived in Florida this time; the animals are illegal to have or import in the U.S. without a permit. 

Greg Hodges, the assistant director of the state's division of plant industry, noted in the briefing that unlike previous detections, these snails have light cream-colored bodies with a dark, mottled brown shell.

“The populations that we dealt with in the previous two eradications had dark gray to brown bodies,” he explained. “This cream colored phenotype is very common in the pet trade in Europe and has been intercepted here in Florida previously with the illegal pet trade.”

Following the first sighting this year, Florida set up a quarantine zone in the city New Port Richey, making it “unlawful to move the giant African land snail or a regulated article, including but not limited to, plants, plants parts, plants in soil, soil, yard waste, debris, compost or building materials, within, through or from a quarantine area without a compliance agreement,” per the Florida Department of Agriculture and Consumer Services website.

The properties where the snails were found will be treated with the slug and snail killer metaldehyde over the next 18 months and the area will be monitored for two years after the last snail is found, per Field and Stream’s Ashley Stimpson. 

Florida will also use specially trained dogs to sniff out the invaders. 

“Because agriculture is such a prominent part of our economics in the state, it is so imperative we get in front of these things immediately,” Fried said in the briefing. “Let me assure you: We will eradicate these snails. We have done it twice before, and we will do it again – it is not a question of if, it’s just when.”

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