A 19-year old spotted his opportunity to hitch a ride on a whale shark recently while on vacation in the Gulf of Mexico and took it, grabbing the creature’s fin for a photo op.

Chris Kreis, who was with his family at the time, saw the 30-foot long shark coming at him in the water and knew he had to take a chance.

“I decided, you know what, maybe I should go try and swim with him. I might not be able to do it ever again,” Kreis told ABC News. “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.”

The ride didn’t last long, however; Kreis says the whole thing took maybe nine or ten seconds.

Whale sharks are gentler than some of their counterparts, feeding mostly on plankton. They can grow to be quite large, however, some as long as a school bus. But despite their calm nature, experts say it’s dangerous to make contact with them.

“When people spend a lot of time and pressure on a fish it takes away a slime that covers the fish,” marine biologist Bruce Neill told NBC2. “They need that layer to stay healthy. Losing it potentially has negative health impacts for the fish.”

There have been other stories in recent months of people interacting with water-dwellers; one woman was arrested after photos of her hitching a ride on a manatee went viral, and two men allegedly baited a mother manatee and her baby with a water hose in Florida before doing cannonballs in the water, right on top of them. The men faced stiff fines for the act, as it is illegal in Florida to harm or harass the animals.