Falling iguana season: a field guide

Most of the year, the only thing falling out of Boca’s trees is a coconut. Then a cold front comes through, the overnight low drops into the 40s, and the iguanas start coming down.

Why iguanas fall

Green iguanas are cold-blooded and not native to Florida. They rely on the sun to stay warm, and they like to sleep high up in trees. When temperatures fall into the 50s, they get sluggish. Somewhere around 40°F they can become “cold-stunned”: their muscles stop working, they lose their grip on the branch, and down they go.

It happens often enough that South Florida weather forecasts have been known to mention it when a hard freeze is coming.

Are they dead?

Usually not. A stunned iguana looks lifeless, but most warm up and walk away once the sun comes out. Long stretches of real cold can kill them, which is what happened during a two-week cold snap in 2010.

If one lands in your yard

• Leave it alone. The Florida Fish and Wildlife Conservation Commission warns that iguanas can bite and scratch when they warm up and feel threatened.
• Don’t bring it inside. Not into your house, and definitely not into your car.
• Call a professional if you want it removed from your property.

Stay warm, look up, and dress for the occasion: the Falling Iguana Advisory hoodie is made for exactly these three days a year.