What Are Tiger Sharks?

Tiger sharks are members of the species Galeocerdo cuvier in the family Carcharhinidae. They are among the largest sharks and predators living in the world's oceans. Tiger sharks are found in almost every area of the tropical and temperate seas. They are powerful swimmers, able to travel up to 50 miles in a day. Tiger sharks have a very recognizable body shape with a large wedge-shaped head and muscular upper body paired with a slender lower body and tail.

Members of the species can weigh over 2,000 pounds (about 900 kg) but average specimens more often range from 850 to 1,400 pounds (about 385 to 635 kg.) Males average about 10.5 feet (3.20 m) while females usually average about 9.60 feet (2.92 m) in length. Individuals up 24.5 feet (about 7.5 m ) have been recorded.

Tiger-like stripes on the sides of some juveniles are what gave the species their common name. On some these appear as spots, rather than stripes. The stripes are faded or non-existent on most adult tiger sharks. Both juveniles and adults are bluish-gray to greenish-gray with lighter white or yellow underside.

Coastal areas with shallow muddy water are usually the preferred hunting grounds for tiger sharks. Tiger sharks are nocturnal creatures, preferring to hunt at night. During the day they are usually found in the deeper water off the coastal shelf. They also hunt on coastal reefs and in areas where sea grass grows near shore.

Fish, including smaller sharks, sea turtles, and marine mammals such as seals are an important part of the tiger shark's diet. Other common prey are mollusks and seabirds. In addition to hunting, the tiger shark scavenges in shallow water and around reefs.

Tiger sharks are among the minority of sharks that are ovoviviparous. A female keeps the fertile egg capsules within her body where the young grow, each nourished by its individual yolk sac. When the pups are fully ready to live on their own they emerge from the egg sacs within the mother's body and are then expelled into the ocean.

After a gestation period of 13 to 16 months, the mother gives birth to between 10 and 80 young in each litter. The pups range from 6.5 to 13 pounds (about 3 to 6 kg) in weight and are 20 to 30 (about 51 to 76 cm) long. Young tiger sharks receive no parental care and are ready to live independently when born.