FLORIDA - DM - When Florida teen Chris Kreis came face to face with a 30-foot, 50,000-pound whale shark while fishing in the Gulf of Mexico last week, he knew exactly what to do: hop on the animal’s back and go for a spin.

The incredible encounter happened last Saturday 30 miles off the Captiva's coast, where the 19-year-old ran into the boat-sized fish. Kreis jumped on the shark's back, grabbed hold of its fin and rode it for about 20 seconds. He later posted a video of his adventure on YouTube.

‘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 described the experience in an interview with a local TV station NBC 2.

Whale sharks are the largest fish in the sea reaching lengths of 40 feet or more. Despite their fierce name and appearance, they mostly feed on plankton and small fish.  Marine biologist Bruce Neill told the station that the docile fish could have been injured as a result of the ride.

‘When people spend a lot of time and pressure on a fish it takes away a slime that covers the fish. They need that layer to stay healthy,’ Neill said. 

Kreis boasted on Facebook last week that his encounter with the critter was an 'unbelievable experience.'

When interviewed about it by NBC later, the 19-year-old confessed that he had no idea that his actions could be harmful to the animal’s health.  ‘I would jump in if I saw one again, but next time I wouldn't touch the fish,’ Kreis promised.

Kreis’ YouTube video has drawn more than 100,000 views since he posted it on Wednesday.  The description of the 30-second clip stated that ‘no harm was done to this shark.’ The Pygmy Marmoset or Dwarf Monkey is one of the smallest primates and ties with the Slender Loris for smallest monkey. The Dwarf Monkey averages 14 to 16 cm in length (15 to 20 cm including its tail) and weighs 4.2 to 4.9 oz. Native to the rainforest canopies of Brazil, Columbia, Ecuador, Peru, and Bolivia, the Dwarf Monkey often snacks on gummy tree sap.

The Pygmy Marmoset or Dwarf Monkey is one of the smallest primates and ties with the Slender Loris for smallest monkey.

 The Dwarf Monkey averages 14 to 16 cm in length (15 to 20 cm including its tail) and weighs 4.2 to 4.9 oz. Native to the rainforest canopies of Brazil, Columbia, Ecuador, Peru, and Bolivia, the Dwarf Monkey often snacks on gummy tree sap.