Tiger Shark Galeocerdo cuvier
Tiger sharks are one of the top three sharks implicated in unprovoked, fatal attacks throughout the world. Although shark attacks are a relatively rare phenomenon, the tiger shark is responsible for a large percentage of fatal attacks and is regarded as one of the most dangerous shark species.
Description
The tiger shark has many distinctive characteristics making it easy to distinguish from other sharks. The tiger shark is named for the dark black spots and vertical tiger-stripe markings that are very prominent in juveniles but that often fade as they mature. It has a short, blunt snout, and a big mouth with large, saw-edged, cockscomb-shaped teeth.
This is one of the larger shark species; tiger sharks usually range from between 3 to 5 metres in length. Although much larger specimens have been seen, the largest a tiger shark tends to get is around 5.5 metres long.
Range and Habitat
The tiger shark is found in warmer and tropical waters in the Southern Hemisphere. The tiger shark tends to be found in more coastal waters but tigers sharks are also known to go into the deeper ocean if they need to hunt for food. They seem to prefer turbid coastal areas where fresh water runoff occurs as different prey species may congregate to feed in these areas. They are commonly found in river estuaries and harbors.
In North America, they are found on the East coast from Massachusetts down to the Gulf of Mexico and the Caribbean. On the West coast, they are found in Southern California and in Hawaii. They are also known to seasonally migrate, moving from temperate to tropical waters in the winter; they also make long migrations between islands in the Pacific. Other locations where tiger sharks are seen include Africa, People's Republic of China, Hong Kong, India, Australia and New Zealand.
Diet
These solitary hunters are nocturnal and move inshore into shallow waters at night to feed and then move back to deeper waters in the daytime. Their diets include bony fishes, sharks, rays, porpoises, turtles, crabs, squid, birds, and even garbage. They are not picky eaters.
Shark-Human Encounters
While the tiger shark is considered to be one of the sharks most dangerous to humans, the attack rate is low considering the thousands of people who swim, surf and dive in the ocean every day. The tiger shark is second only to the great white shark in number of reported attacks on humans. Tiger sharks often visit shallow reefs, harbors and canals, greatly increasing the potential for encounter with humans. It’s not known why tiger sharks sometimes bite humans. The idea that they mistake a person for a natural prey item, such as a turtle, is not supported by any evidence. The shark may be trying to determine if a person is a potential prey item, it may come across a person while in a feeding “mode,” or perhaps there is some other explanation. According to the International Shark Attack File (ISAF), there were only 75 confirmed cases of unprovoked shark attacks on humans world wide in 2011.
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