A Florida teen saw an elusive whale shark while on a fishing trip; he jumped right in and rode the huge creature.

Chris Kreis, 19, spotted the 30-foot long whale shark off the Gulf of Mexico, according to NBCMiami. The shark is believed to weigh about 50,000 pounds. Someone on the boat told Kreis it might be the only opportunity he would ever have to see one of the rarely spotted sharks, so he chose to dive in and swim with it.

"It went through my mind, yeah. I might not be able to do it again, so I did it," Kreis said. "It was incredible."

The teen grabbed onto the shark's fin and took a ride that lasted only seconds, but was caught on video by his buddies.

"When I started holding on I felt the whale shark it started moving itself, it felt the drag and it didn't really want me on there so I let go and that's it," Kreis said.

Marine biologist Bruce Neill raised concerns that both Kreis and the shark could have been injured in the escapade. Kreis could have gotten hurt if the whale shark had attacked him, but the aquatic creature could have been injured if the slimy skin on it's fin had been damaged.

"It takes away that slime covering and potentially has negative health impacts on the fish," Neill said.

Whale sharks only feed on aquatic plants, such as plankton, but they can still be dangerous.

"Because they are so very large, they could inflict some harm inadvertently," Neill said, according to Nature World News.

The teen also spotted two bull sharks, the most dangerous and aggressive of their kind, swimming in the area. After spotting them he swam back to the boat "really quickly." Kreis told NBCMiami he was unaware of the possible danger to both him and the shark, and had he known he would have been more careful.

"If I had known about that, I would have probably just swam with it and not touched it. But since I didn't really know, I kind of feel bad," Kreis said. "But again, it was a once in a lifetime experience."

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