Come in, the water's just fine! Okay, you won't be hearing any alligators saying that, but as these amazing images show, these restricted reptiles are taking the cold snap in their stride – even if their swampy home has transformed into a glittering prison of ice.

Like snorkelers who picked a particularly bad time to take a dip, these alligators at Shallotte River Swamp Park in North Carolina are trapped in frozen waters – and in these hostile, icy conditions, an ancient survival mechanism is kicking in.

Ordinarily, these alligators would be spending their time sun-bathing or resting along the bottom of their swamp, but in a video captured by staff at the Swamp Park, we can see the animals adopting a very different pose on account of the punishing cold spell currently blasting the US.

935 alligator frozen ice swamp 4(Swamp Park/YouTube)

What they're doing is called brumation, which is similar to hibernation, and involves the reptiles' metabolism slowing down dramatically and going into a lethargic state, in response to very cold temperatures.

Usually, these alligators would brumate at the bottom of their swamp, coming up at least once a day for air. These are not usual times, however.

In the aftermath of a bomb cyclone, it looks like the alligators are adopting a different survival strategy, positioning themselves – or at least their snouts – at the surface of their frozen swamp, giving them ready access to air while the bitter winter persists.

"It's an interesting behaviour because it's opposite of what most crocodilians do," retired ecologist James Perran Ross explained to Live Science.

"The normal response of most other crocs when it gets really cold is to come out of the water and try to bask to get warm again."

That might not be an option here, though – because of bomb cyclone weirdness generally, and the colder-than-usual air temperatures the US is currently weathering as a result, which could be dangerous to unsheltered alligators.

"They can sense temperature changes and will stick their noses out of the water to breathe," the Swamp Park's general manager, George Howard, told HuffPost.

"In that state, they are still alive, still moving, but very lethargic."

935 alligator frozen ice swamp 4(Shallotte River Swamp Park)

It's an incredibly cool (ahem) survival trick, but it's not something alligators can pull off indefinitely.

Alligators can live in water temperatures as low as 4 degrees Celsius (40 degrees Fahrenheit), but in icy conditions like this, Howard reckons the reptiles would only survive for about a week.

Luckily for all concerned, the ice you're seeing here ended up thawing a few days later, meaning this frosty crew can look forward to many warmer times ahead.

"It's 65 degrees [Fahrenheit] here today and the waters have melted," Howard said on Tuesday.

"They're out and doing their happy dance."