what happens to iguanas when it gets cold

When it gets cold, iguanas essentially shut down : their bodies slow so much that they can become stiff, immobile, and even fall out of trees, but many of them “wake up” again once it warms up.

What actually happens to iguanas in the cold

• Iguanas are cold‑blooded (ectothermic), so they rely on external warmth like sun and air temperature to keep their body working.

• When air temperatures drop to around 50 °F (10 °C), their metabolism and muscles slow down and they become very sluggish.

• As it gets colder (mid‑40s °F and below), they can enter a “cold‑stunned” or dormant state where they lose their grip and often fall from trees where they sleep.

• On the ground they may look dead: barely moving, very stiff, often lying on their side or back, but they are usually still breathing with basic body functions ticking over.

• When temperatures climb back toward 50 °F and above, many of these iguanas slowly “defrost,” regain movement, and eventually walk or run away as if nothing happened.

When cold becomes dangerous

• Short cold snaps in the 40s °F typically cause temporary cold‑stunning, not instant death.

• Prolonged exposure to colder than about 45 °F, especially into the 30s °F, can be fatal because their organs and circulation can no longer function properly.

• Some guides note that extended periods near or below freezing (around 32 °F) are particularly risky and can kill iguanas that can’t find warmer shelter.

The “falling iguanas” alerts in Florida

• In places like Florida, green iguanas sleep up in trees; during sudden cold snaps, people really do see them dropping out of branches onto the ground, patios, and sidewalks.

• Weather outlets and local news sometimes issue tongue‑in‑cheek “falling iguana” alerts when forecasts call for lows in the 30s–40s °F, because so many stunned iguanas can fall at once.

• Online forum discussions also joke about Florida having “iguana forecasts” and how surreal it is to worry about lizards falling on your head, which has helped turn this into a recurring viral topic each winter.

What people are advised to do

• Wildlife and weather experts generally say: don’t pick them up, especially large ones, because they can wake up suddenly and scratch or bite.

• The usual advice is to leave cold‑stunned iguanas alone outdoors; many will recover naturally once the sun comes out and the air warms.

• If iguanas are invasive in the area (as in much of Florida), authorities may have specific guidance on whether or how they may be removed or controlled, since they can damage vegetation and infrastructure.

Quick TL;DR

• Around 50 °F: iguanas get sluggish and slow.

• Mid‑40s °F and colder: they can become cold‑stunned, stiff, and fall from trees but are often still alive.

• Long periods below roughly 45 °F, especially near freezing: many will not survive if they can’t reach warmth.

Information gathered from public forums or data available on the internet and portrayed here.