Are there alligators in Hawaii

Why alligators let themselves freeze voluntarily in winter

by Solvejg Hoffmann
In parts of the USA, there is a fascinating natural spectacle in extremely cold winters: alligators freeze in the swamps and ponds. What initially looks hostile to life turns out to be a clever survival strategy

The winter time sometimes brings with it rare weather phenomena and natural spectacles. In parts of the USA, the icy winters in recent years have regularly resulted in very special images: the sharp-toothed mouths of alligators protrude from the frozen surface of the water and offer a bizarre sight.

In 2018 and 2019, for example, the alligators froze in the swamps of the Shallotte River Swamp Park in North Carolina. This winter, American media reported frozen alligators in lakes in Oklahoma.

Mississippi alligators instinctively sense when a body of water freezes over

The animals seem lifeless in the ice. The bodies can be seen outlined under the icy surface of the water, only the snouts sticking out of the ice. What at first looks like an involuntary shock freeze, on closer inspection, is a clever survival trick.

The reptiles are neither accidentally frozen nor are they dead. Instead, the Mississippi alligators, which live in the southeastern United States, are deliberately frozen in order to be able to survive extreme cold spells.

Alligator mississippiensis instinctively knows when the water at home will freeze over. However, since frozen water is an absolute death trap for him, the alligator enters the water at the right moment and sticks its nose out before freezing - so that it can continue to breathe despite the ice cover. Then the animal falls into a state that is biologically known as "dormancy" and is similar to hibernation in warm-blooded animals. The metabolism is shut down, body functions are reduced to a minimum and energy is saved.

In this position, the Mississippi alligators are able to survive for up to two or even three months despite the extreme cold. They just wait for the temperature to rise again and the ice to melt. Then the reptiles adjust their body temperature and wake up from the rigor.

The animals spend milder winters comfortably buried in the bank mud or in deeper layers of water.