Shiver me timbers! A whale shark!

Whale Shark
Credit: davidevison/Getty Images

Whale sharks aren't something fishermen are used to seeing off the coast of South Carolina. Luckily, 21-year-old Michael Krivohlavek, was ready with his camera when the unexpected happened last month.

Krivohlavek, the mate on a charter fishing boat, captured incredible footage of a gigantic whale shark that just "popped up behind" his boat in 150 feet of water about 36 miles off Charleston on October 14th.

"He was very interested in the boat," Krivohlavek recalled to Myrtle Beach Online, adding that the plankton-loving shark "did a couple circles around the boat" to check it out.

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Whale sharks are the largest fish in the sea and can grow to more than 40 feet long and weigh 20 tons. "Although massive, whale sharks are docile fish and sometimes allow swimmers to hitch a ride," National Geographic reports.

Krivohlavek told Myrtle Beach Online that he estimated the shark was between 20 and 25 feet long.

Preferring warm waters, whale sharks call the world's tropical seas home. Krivohlavek said he's seen whale sharks in Mexico, but never off South Carolina. "It's pretty rare," he added.

Watch Krivohlavek's incredible run-in above.