Alligators in North Carolina went into a deep freeze this week as a blast of winter cold gripped the region. Gators at The Swamp Park in Ocean Isle Beach froze in place with their noses sticking out of the icy water so they can breathe, The Associated Press reports.

Swamp Park manager George Howard said 18 American alligators at the park froze Monday night and stayed frozen all day Tuesday, The Charlotte Observer reports. The alligators seem to sense when the water is about to hit the freezing point and they poke their noses into the air "at just the right moment," Howard said.

When the water or air temperatures dip too low for them to be active, the cold-blooded reptiles go into a "state of brumation," Howard said. Brumation is a hibernation-like state for reptiles.

Photos of the frozen gators at the Swamp Park went viral last year, too. The Swamp Park

The same phenomenon happened last winter, when gators in the 65-acre park and sanctuary froze with their noses sticking out of the swap and the images went viral. Those alligators thawed out within days and had no apparent injuries as a result of their deep freeze, Howard said.

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Alligators can live in water temperatures as low as 40 degrees, the staff of the Shallotte River Swamp Park wrote in a blog post. "This is where a reptile's metabolism slows down dramatically and will go into a lethargic state," they said.

"Often during this time, an alligator will stay at the bottom of a body of water. An alligator can hold its breath underwater for 1 to 24 hours."