Reptiles are cold-blooded creatures, which means they regulate their temperature from the environment around them, but the problem with that is, what if the temperature drops down to freezing? Well luckily, crocodiles have a way to fight that! They have a process called "brumation", which enables them to shut their body down and sleep all through the winter time, just waking up to drink or breathe if they're underwater, similar (but not same) to mammals hibernation.

More information:

sciencealert.com/how-alligators-stuck-frozen-swamps-spending-winter-brumation-hibernation