why do iguanas freeze

Iguanas “freeze” because cold weather slows their cold‑blooded bodies so much that they enter a temporary paralysis called cold‑stunning, often losing muscle control and even falling from trees, but many recover once they warm up again.

Quick Scoop

What “freezing” really means

• Iguanas are ectothermic (cold‑blooded), so they rely on outside heat to keep their bodies running.

• When temperatures drop into the low 50s °F and especially the 40s °F, their muscles and nerves slow dramatically.

• Below about 45 °F, they can enter a cold‑stunned state: they go limp, breathing slows, and they may look dead even though the heart is still beating.

Why they fall from trees

• Green iguanas in places like Florida spend a lot of time high in trees to bask in the sun and avoid predators.

• When a sudden cold snap hits at night, their grip weakens, they lose muscle control, and they can literally drop out of the branches onto the ground, sidewalks, or cars.

• This now happens often enough in Florida winters that “falling iguana” alerts sometimes make the news and social media, turning it into a trending winter oddity.

Is the iguana actually dead?

• In many cases, the lizard is not dead; it is in a kind of protective shutdown (torpor) to survive the cold until temperatures rise above roughly 50 °F.

• If the day warms slowly, the animal may “wake up,” regain movement, and climb away.

• Prolonged or very intense cold can still be fatal, especially if tissues start to freeze internally or if their digestion stops and leads to infection.

Why this is a “Florida thing” now

• Green iguanas are tropical lizards from Central and South America that became widespread in Florida only in recent decades.

• Because they are not adapted to real cold, even a brief South Florida cold snap can trigger mass cold‑stunning events, which is why “why do iguanas freeze” keeps popping up in news and forum discussions each winter.