What would you think if you saw an alligator’s snout sticking out of a frozen pond or lifeless iguana falling out of trees? In North Carolina at the Shallotte River Swamp Park in Ocean Isle Beach, alligators look frozen but are very much alive.  Mammals go into a state of brumation–a dormant state–to survive the cold temperatures.

Brumation is similar to hibernation except that the animal does not sink into a deep slumber like a hibernating bear.  The reptile’s breathing and heart rate slow down in order to save energy. The alligator does not eat during brumation, but it does drink water. The sun helps maintain its body temperature.  The alligator’s snout may be very cold, but the rest of their body, which is deeper in the water, is warmer.

The “icing” technique is something developed over time through natural selection and is not successful every time.  In 1982, scientists examined an alligator “icing” but three days later it died because its body temperature was too low to survive. In 1990, scientists in South Carolina found that the baby alligators didn’t know the “icing” technique, and watched the baby alligators banged their snouts on the ice, trying to break it, before they drowned.

Alligators are not the only species of reptiles that take extreme measures in order to survive the cold temperatures.  In Florida, iguanas were found on the ground stiff as they entered brumation. The iguanas were literally falling out of trees! When local residents found them they were gray and stiff but when the temperatures rose–when they basked in the sun–they eventually started their rejuvenation process.

Next time you see alligators snouts sticking out of an ice-cold pond or iguanas falling out of trees, you might have an inkling as to why this fascinating scientific phenomenon occurs.  

Sources:

https://www.cbsnews.com/news/alligators-frozen-north-carolina-swamp-with-noses-above-ice/

https://www.washingtonpost.com/nation/2019/01/25/scientists-say-these-frozen-alligators-arent-dead-theyre-still-creeping-people-out/?utm_term=.a856e0144e49

https://www.inverse.com/article/52751-frozen-alligators-north-carolina-brumation