A Giant African land snail is seen as the Florida Department of Agriculture and Consumer Services announces it has positively identified a population of the invasive species in Miami-Dade County on Sept. 15, 2011.
Joe Raedle—Getty Images
August 2, 2015 3:19 PM EDT

Giant African snails that can grow to the size of a tennis shoe are thriving in southern Florida, eating hundreds of plant species and even the stucco off houses more than four years after the state launched a $10 million program to eradicate them.

The snails were first discovered in Miami in September 2011, AFP reports, the first invasion since the 1960s. Since then the species has spread to new territory, including the southern suburbs of Miami and the neighboring Broward County.

“The fact is they’re a human and animal health threat and they’re a threat to Florida’s agriculture. We can’t let the population continue,” said Mark Fagan, a spokesman for the state agriculture department.

The giant African snails have continued to elude the state’s eradication efforts, which can prove fruitless when the gastropods climb trees to avoid chemicals on the ground, or hibernate below the soil for months at a time.

Still, over 158,000 giant African snails have been removed in the past four years, with the last sighting reported in April, officials said. Two years must pass since the last snail is found alive in the wild for the state to declare the species eradicated.


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