Tiger shark (Galeocerdo cuvier): a species of ground shark.
Kingdom: | Animalia
Phylum: | Chordata
Class: | Chondrichthyes
Order: | Carcharhiniformes
Family: | Galeocerdonidae
Genus: | Galeocerdo
Species: | G. cuvier
Size and Weight:
Tiger sharks are one of the largest shark species. On average, they measure 10 to 14 feet and weigh 850 to 1,400 pounds. But they can be as long as 20 to 25 feet and weigh more than 1,900 pounds. These sharks are sexually dimorphic, with females being the larger sex.
Appearance:
Tiger sharks are named for their distinctive dark, vertical stripes, found mainly on juveniles. As they age, these lines begin to fade. Their skin color ranges from bluish or greenish gray to black with a light gray to dirty yellow underbelly. They have a broad, flat head with a snout shorter than the width of the mouth, long labial furrows and a slender body.
Diet:
Tiger sharks are known for having the widest food spectrum of all sharks. Their diet is nearly limitless, including stingrays, sea snakes, seals, birds, sea turtles and squids. They are also known as “garbage eaters,” consuming a variety of inedible, man-made objects like license plates and old tires. To hunt, they use their excellent senses of sight and smell. Their sharp, highly serrated teeth and powerful jaws allow them to crack the shells of sea turtles and clams. Tiger sharks are second only to the great white in recorded fatal attacks on humans, but these events are exceedingly rare.
Habitat:
Tiger sharks inhabit tropical and subtropical waters around the world.
Geography:
Their range includes the world’s temperate and tropical waters, except the Mediterranean Sea.
Breeding:
Tiger sharks mate via internal fertilization. The tiger shark is ovoviviparous, meaning the young are born alive but are not nourished through a placenta. Instead, tiger shark embryos develop from relatively large eggs in the initial stages of development. After a gestation period of 13 to 16 months, a female gives birth to 10 to 82 pups. Pups are generally 25 to 34 inches long at birth. Males and females reach maturity when they are between 4 to 7 years old.
Social Structure:
Tiger sharks are solitary.
Lifespan:
Their lifespan is unknown but estimates range from 20 to 50 years.
Threats:
Tiger sharks are hunted for their fins, skin and livers, which contain high levels of vitamin A. They have extremely low repopulation rates and are highly susceptible to fishing pressure.
Conservation Status:
The tiger shark is classified as Near Threatened by the IUCN’s Red List of Threatened Species.
Sources: Government of Canada and the Florida Museum.