KEY WEST, Fla. -- Dylan Gartenmayer has been diving and spearfishing along the Florida coast since he was 10. That experience helped him survive a frightening ordeal that left him stranded at sea for hours.
The 21-year-old was free diving at the Western Sambo Reef near Key West Thursday afternoon when a strong current swept him away from his boat.
By the time he resurfaced, the current had pulled him so far away that his two friends never saw him come back up. He soon disappeared from view, his cousin Priscilla Gartenmayer told CNN.
His friends scoured the choppy waters for half an hour, then called the Coast Guard to help in the search. Gartenmayer could still see the boat, he told people later, but they couldn't see him.
Gartenmayer came across a bamboo stick and used it to help him float until he was able to swim across the current back to the reef, his cousin said.
By the time he'd made the roughly two-mile swim, it was about 5 p.m. and his friends had left because their boat didn't have any lights, his cousin said.
Exhausted, Gartenmayer cut three buoys to create a hammock-like device that helped him stay afloat. While he was focused on survival, his friends and family worked frantically to find and rescue him, his cousin said.
"I got a call from someone on the boat that Dylan was diving from that he was missing for two hours and I had them send me the coordinates," his friend Sean Caggiano told CNN. "I went to his grandfather's house to get with his family and go find him."
Within 15 minutes, family and friends gathered and jumped into their grandfather's boat to go find Dylan, Priscilla Gartenmayer said.
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"The first thought was that he blacked out while diving and drowned. It was horrible -- the worst feeling I've ever felt," she said.
The family plugged in the coordinates of the location where Dylan was last seen and dashed that way at high speed. The light was fading, and they didn't have much time before darkness would make their rescue effort more difficult.
"Everything was silent on the boat until the flashlight hit him and he put his hands up -- we finally knew he was OK," Priscilla Gartenmayer said.
In a video of the rescue posted on Facebook, his family members jumped up and down when they spotted Dylan alive.
Moments later, his family pulled him, shivering, onto the boat. Videos shared to Facebook show his family members hugging and squeezing him, crying "Oh my God" and saying his name over and over. Dylan's first request was for water, his cousin said.
CNN has reached out to Dylan Gartenmayer to hear his account of the ordeal.
The Coast Guard arrived, checked on Gartenmayer and discovered his core temperature was slightly low. They took him to the station for observation for about an hour until it was back to normal, his family said. CNN has reached out to the Coast Guard for comment.
Dylan Gartenmayer has been diving and fishing consistently for 11 years. His Instagram account is full of photos of him holding pompano, grouper, red drum, wahoo and other fish he has caught.
"If he was anyone else, I don't think it would've been the same outcome," Priscilla Gartenmayer said. "He still knew where he was, he knew which way land was. That's the reason he survived."
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