Tiger Shark

The Tiger Shark (Galeocerdo cuvier), named for the dark strips on its gray back, which is pronounced in juveniles but become pale or disappear in large adults, has tiger-like markings on a dark back with an off-white underbelly. Pups have spotted markings that grow together to form stripes that fade with maturity. It has a large, thick-body with a blunt snout. The first dorsal fin is much longer than the second. The caudal fin is long and pointed. There is a dermal ridge along the back between the 2 dorsal fins.

Its wide mouth, broad nose, barrel chest, and the slenderness at the base of its tail are distinctive. So, too, are its heavily serrated, cockscomb-shaped teeth. These, combined with its jaw strength, allow it to cut the bodies of large sea turtles, as well as seals, sea lions, and cetaceans.

Tiger sharks have a special gill slit (a spiracle) behind the eyes that provides oxygen flow directly to the eyes and brain. It also has a very good sense of smell, electroreceptors sensitive to electric currents in the water, and keen eyesight.

They are active at night, and enter shallow reefs and lagoons after dusk to feed. In certain areas they migrate between island groups to take advantage of colonies of young birds learning to fly over water. Generally, tiger sharks are sluggish, but they can move quickly when feeding, and should be treated carefully on the rare occasions they are sighted. If you see one while diving, calmly leave the water, keeping it in sight at all times.

Adult tiger sharks spend their days beyond the reef edge to depths of about 500' (150m), except at certain times of the year, when they also come inshore during the day.

The tiger shark ranges world-wide in tropical waters, but has been spotted in the Bay of Fundy at the mouth of Le Preau tangled in fishing weir. It is found throughout the world's temperate and tropical waters, with the exception of the Mediterranean Sea. It is a wide-ranging species that is at home both in the open ocean as well as shallow coastal waters. Reports of individuals from as far north as Iceland and the United Kingdom have been confirmed but are probably a result of roaming sharks following the warmer Gulf Stream north across the Atlantic.

This shark has a notable tolerance for many different kinds of marine habitat but generally prefers murky waters in coastal areas. It is commonly found in river estuaries, harbors, and other inlets where runoff from the land may attract a high number of prey items. Shallow areas around large island chains and oceanic islands including lagoons, are also part of the tiger shark's natural environment. It is often seen at the surface and has been reported to depths of 1085 ft (350 m).

Tiger sharks undergo seasonal migrations. It is well known that they move into temperate waters from the tropics for the warmer months and return during the winter. These sharks also make long oceanic migrations between islands and are capable of traveling long distances in a short amount of time.