Why you should never attempt to kiss a shark - even a 'harmless' nurse shark

Diving guide Dave Marcel had been taking tourists out on Elbow Reef off Key Largo, Florida for years - allowing them to interact with the reef's wildlife including the 300-pound nurse shark.



These sharks are not usually aggressive, and love being petted.

Marcel would prove their harmlessness by kissing the sharks, and then allowing the tourists to do the same.



Until the day one of the sharks bit back.

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Diving guide Dave Marcel was used to kissing harmless nurse sharks, but this shark decided to bite back

The shark bite was caught on camera and aired on Discovery Channel as a part of this year's 'Shark Week.'

Marcel's key mistake that day was flipping the shark upside down before planting a smooch - something he hadn't done before.



Marcel didn't realize that since the shark's eyes are on top of it's head, it wouldn't see him and would assume he was being fed fish.



Instead of passively receiving the peck, the shark bit down with all 500 of it's razor-sharp teeth.

Lesson of the bite: don't kiss a shark Spider-Man style.

Crucial mistake: Marcel's mistake was flipping the shark upside down - rendering the shark blind to what was in front of it. The shark just assumed the diver was food

Predators: Nurse sharks generally weigh around 300 pounds and have 500 razor sharp teeth. They can suck a conch right out of its shell

Once the shark realized it was eating human flesh and not fish meat, it lost interest and swam off.



'He spit me out. I guess he said I didn't taste good,' Marcel told the Discovery Channel .



Discovery Channel's Jeff Kurr also pointed out to the Huffington Post that while these sharks are docile, their anatomy is rigged to do major damage.



He said nurse sharks can suck a conch right out of it's shell.

Luckily for Marcel, the bite didn't leave his face deformed. But it still required 285 stitches. He compared the painful bite to a firecracker going off in his mouth.



The damage: Surprisingly, Marcel escaped the attack and didn't look too bad. The bite did require 285 stitches though

Marcel, not about to let a shark bite get him down, was out in the water again three days later.

'You can not be a wild animal handler without having the expectation that you will be bitten,' Marcel said. 'It's a part of the job.'