This past week’s extreme cold snap caught many Floridians by surprise. We sought out winter clothes long forgotten, discovered whether or not our homes had heat, and laughed at all of the iguana memes…yes, that’s right. Whenever cold weather hits, with it comes warnings of iguanas falling from trees.
While this may seem like comedic fodder, this is an actual phenomenon. Unfortunately, southeast Florida serves as primo real estate for more than 600 non-native species of fish, reptiles, and other wildlife (UF Invasive Species Institute); Green iguanas, Burmese pythons, and Argentine tegus among them. The Florida Fish and Wildlife Conservation Commission (FWC) has modified regulations surrounding invasive species to encourage public participation in management, and without these efforts, we would barely be able to control the continuing growth of the invasive populations.
Why are invasive reptiles a problem?
In particular, Green iguanas cause damage in many ways. They consume a tremendous amount of plant material including berries, flowers, and fruit. Iguanas will also eat insects, animal eggs, and other small prey. This consumption can have serious negative effects, both ecologically and aesthetically. Iguanas also dig burrows, which can disrupt infrastructure such as sidewalks and seawalls. Since they can swim, they will often avoid capture by diving into water, whether it be the ocean, a canal, or a backyard pool.
What is the advantage of cold weather?
Reptiles are ectothermic (cold-blooded) which means that they rely upon their surrounding environment to regulate their body temperature. When temperatures stay cold for a few days, iguanas and other reptiles (including sea turtles) can become cold-stunned, which puts them into a deep, slumber-like state. This state is often what precedes their dropping from trees (think about it, when you fall asleep, your head starts bobbing around, people take embarrassing photos of you, etc.). This torpor results in the iguanas being more approachable to capture and remove from an area. In fact, these cold fronts are often one of the most effective iguana eradication opportunities for resource managers.
Prior to this weekend’s cold front, FWC issued an executive order, encouraging the safe capture and transport of cold‑stunned iguanas to five designated FWC offices, where they could be handled responsibly and humanely. This effort reflects FWC’s continued commitment to working hand‑in‑hand with the public on invasive species management.
The agency has a long history of empowering community participation, such as making it easier for divers to remove invasive lionfish by waiving saltwater fishing license requirements and sponsoring large-scale roundup events that have successfully removed thousands of lionfish in a single day.
Although the total number of iguanas collected between Sunday and Monday is still being compiled, the initiative is already helping raise awareness and encouraging Floridians to play an active role in protecting our natural resources. The hope is that this executive order will continue to strengthen public engagement and support thoughtful, science‑based management of Florida’s unique ecosystems.
References:
https://invasionscience.ufl.edu/
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