Feb. 16, 2026, 12:46 p.m. ET
- Invasive iguanas have been added to Florida’s “Dirty Dozen” list of most virulent invasive species.
- A recent Arctic cold front caused a large culling of the iguana population, stunning or killing them.
- Despite the cold snap, experts expect the iguana population to rebound due to their rapid reproduction.
In recent years, South Florida’s growing population of invasive iguanas have been expanding their range into Brevard County.
Now Mother Nature has stepped in to slow that process.
Just weeks after Florida wildlife officials added iguanas to the state’s Dirty Dozen list of its most virulent invasive species, Mother Nature stepped in with her own solution to their damaging spread.
A rare and ruthless Arctic-born cold front tumbled temperatures to near freezing or below freezing in areas as far south as Homestead, halting just north of Key Largo. The days-long chill left iguanas cold-stunned or dead in what is likely the largest culling of the population since the extended wintry weather of 2010.
There were no estimates of the burgeoning iguana population ahead of the frigid early February weather and there are no estimates of how many were felled by it, although they were still falling dead from trees a week after the cold snap.
Still, University of Florida experts said green iguanas and their spiny-tailed cousins will remain on the Dirty Dozen’s most-wanted register because of their profound fecundity.
Male iguanas can reach sexual maturity in as little as 16 months. Female iguanas typically reach reproductive maturity at two to four years of age and can lay clutches of up to 70 eggs each year.
“Distribution and abundance of green iguanas increased after the 2010 freeze,” said UF wildlife ecology professor Frank Mazzotti in an email. “I expect the same to happen here.”
Why Florida’s invasive iguana population is bad
Mazzotti, who oversees UF’s Croc Docs research team, said he has been highlighting the increasing damage done by iguanas, including burrowing into flood control canals and levees, digging under sidewalks, defecating in pools, and eating expensive landscaping.
“It’s not been on people’s minds as something they have to deal with, like Burmese pythons and black and white tegus,” Mazzotti said in a 2025 interview. “We need to start thinking about doing something. It’s no longer a cute backyard problem.”
Iguanas were added to the state’s prohibited species list in 2021, limiting who can own them and prohibiting their sale in Florida.
Wildlife officials designated the Dirty Dozen list years earlier to put a priority on the worst of Florida’s invasive species. It was recently amended to add iguanas, the colorful Peter’s rock agama and the poisonous cane toad.
Removed from the list were two species of chameleons and the Cuban tree frog.
The new Dirty Dozen list was discussed at a 2025 meeting of the Everglades Cooperative Invasive Species Management Area, which has representatives from multiple agencies including the Florida Fish and Wildlife Conservation Commission and South Florida Water Management District.
University of Florida wildlife ecologist Melissa Miller said in January that the changes reflect the evolving nature of invasive species in South Florida as some spread tidal waves of harm into farther reaching territories or proliferate with deadly resolve.
The change is new enough that the cooperative has yet to update its website.
“We really want to focus on animals we know are doing the most harm, or ones that have a high potential to do so, and that’s why we are fine tuning the list,” said Miller, who specializes in invasive species research with UF’s Croc Docs. “It’s kind of subjective because we have so many heavy hitters as far as invasive reptiles and amphibians go.”
Continued mainstays on the list include the Burmese python, black and white tegu, Nile monitor, giant African land snail, bullseye snakehead, lionfish and four plant species. Those include the Australian pine, old world climbing fern, Brazilian pepper and air potato.
Iguanas are easier to catch when they are paralyzed by cold weather
While it’s unknown how many iguanas were killed during the early February cold spell, the Florida Fish and Wildlife Conservation Commission collected nearly 5,200 cold-stunned iguanas through a novel two-day program where people were allowed to drop the temporarily paralyzed animals off at several sites in South Florida.
When temperatures reach between 40 and 50 degrees, iguanas can become temporarily paralyzed, also known as torpor. Iguanas can die if temperatures get too cold or stay cold for longer periods of time, especially if skies remain overcast so that they can’t bask for warmth.
Of the iguana drop off locations, one in Sunrise collected the most iguanas at 3,882. A Tequesta site received 1,075 iguanas. A drop off location in Marathon got 215 iguanas and one in Fort Myers received 23.
About 1,615 live iguanas were placed with permitted handlers to rehome or sell out of state. The remainder were humanely euthanized, with an untold number going to an exotic leathers manufacturer.
Kimberly Miller is a journalist for the USA TODAY NETWORK FLORIDA. She covers weather, the environment and critters as the Embracing Florida reporter. If you have news tips, please send them to kmiller@pbpost.com. You can get all of Florida’s best content directly in your inbox each weekday by signing up for the free newsletter, Florida TODAY, at https://palmbeachpost.com/newsletters.
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