Of the over 500 different species of sharks found in the world’s oceans, only about 30 have been reported to ever bite a human. Of these, only about a dozen should be considered particularly dangerous when encountered. The shark species responsible for most unprovoked bites on humans are the white (Carcharodon carcharias), tiger (Galeocerdo cuvier), and bull (Carcharhinus leucas). All sharks, large and small, are however predators and could be capable of inflicting wounds if provoked. They should all be treated with respect when encountered.
Humans have a fear for sharks that may be in part innately rooted in our past when we did need to be on constant alert for large predators. More importantly, in today’s world we constantly are subjected to the media’s stereotypic characterizations of sharks, which are rife with misinformation and actively promote fear and loathing. Finally, we as humans are used to controlling the world around us – damming rivers, flattening mountains, shooting a charging elephant – but sharks, like typhoons, lightning and tornados, are something we cannot control, hence our great interest in them.
Unprovoked shark bites happen when sharks make the first contact. This can take three forms. Hit-and-Run bites happen near beaches, where sharks try to make a living capturing fish. In pounding surf, strong currents, and murky water, a shark may mistake the movements of humans, usually at the surface, for those of their normal food, fish. Sneak bites take place in deeper waters. The victim doesn’t see the shark before the interaction. The result can be serious injury or death. Bump-and-Bites happen when the shark circles and actually bumps the victim with its head or body before biting. As in the sneak bites, the shark may bite repeatedly and cause serious injury or death.
People often assume that if someone was bitten in the ocean a shark was the only possible culprit. ISAF does thorough investigations of each case to understand the circumstances involved. Many times we find that other marine creatures were the culprit. Common perpetrators include stingrays (AKA flat sharks), moray eels (Muraenidae), bluefish (Pomatomus saltatrix), and barracuda (Sphyraena spp).