Strange looking ‘swirly thingy’ washes up on North Carolina beach. What is that?

At first glance, an object recently found washed ashore in Oak Island, North Carolina might appear to be a spine, or skin sloughed off a shedding snake.

To one visitor, it’s identity was a mystery. So he turned to the experts.

“All right old locals. What is this?” he asked in a Facebook post.

The answers came quickly.

“Some sort of swirly thingy,” a helpful commenter wrote.

“Arby’s curly fry,” said another.

One suggested this: “Sea monster.”

The reality is slightly less exciting. As many pointed out, the strange-looking object is an egg case from a whelk, a type of sea snail.

“Super cool find!!!!” a commenter said. “Sorry I got so excited- I’m a shell nerd.”

They aren’t necessarily a rare sight for regular beachgoers, but visitors lucky enough to stumble across one are often mystified, or creeped out, by them.

Sometimes called “mermaid’s necklaces,” or “fisherman’s soap,” female whelks lay these elongated strands in deep water twice a year, Cape Hatteras National Seashore officials said.

They average 3 feet in length, and each little segment can hold 20 to 100 eggs, which hatch between 3 to 13 months after they’re laid. The young whelks emerge with a shell already formed.

“Whelks keep the same shell their entire life; as the shell grows, the organism inside grows with it,” Cape Hatteras seashore officials said.

The sea snails mostly feast on crabs and other mollusks throughout their lives.

In turn, people sometimes feast on the sea snails, using them as a key ingredient in soup and other recipes, according to North Carolina State University.

There are several species of whelk found along the U.S. Atlantic coast, Pacific coast, and down through the Gulf of Mexico.