All of the sea creatures in this article are known in some parts of the world for being tame and docile enough to encounter face-to-face. But each one has also been known to attack or bite humans on occasion, as well. Any kind of shark, aside from the whale shark, is capable of biting a human. Most sharks aren't interested in people, but a scared or surprised shark can always strike. Another danger is if a shark thinks you're something else. A woman swimming with seals in San Luis Obispo, Calif., in 2003 was attacked and killed by a shark that most likely thought she was a seal.
Seals and sea lions have also been known to bite humans. They generally investigate something by nibbling on it, but those nibbles can turn into more aggressive behavior if they feel threatened. A man in La Jolla, Calif., was clawed and bitten by a sea lion in 2003 during his bid to show the local press that there's no danger of swimming with the sea lions there. The injuries were minor and he was treated and released from the hospital that same day.
If you surprise a stingray, it could respond by defending itself with its sharp barbed stinger. Deaths from stingrays are rare, but Australian wildlife expert Steve Irwin was killed by a stingray in 2006 after it delivered a blow from the stinger directly into Irwin's heart. Stingrays can also bite you with their small, but sharp teeth. Rays are a part of the elasmobranch family along with sharks and both have very strong jaws.
Being in the ocean can be a dangerous environment or completely safe. Even the most feared sea creature, the shark, rarely attacks humans. But just ask the fisherman in St. Augustine, Fla., about the barracuda that jumped into his boat and bit him on the stomach. This happened in 2003, proving that sometimes, even the unlikeliest of things can happen when you're dealing with the ocean.