usa | world | animals | vocabulary | health | science | math | history


The tiger shark (Galeocerdo cuvier) is one of nature's largest sharks. The tiger shark hunts alone, usually at night. Its name is derived from the dark stripes down its body, which fade as the shark matures.


 


Sizes and Scales: A mature tiger shark can average 3.25-4.25 meters (10-14 feet) long and weigh 325-425 kilograms (850-1400 pounds). It is found in many tropical and temperate regions of the worlds oceans, and is especially common around islands in the central Pacific.

On the Menu: The tiger shark is a dangerous predator, known for eating a remarkably wide variety of things. Its usual diet consists of fish, seals, birds, smaller sharks, squid and turtles. It has sometimes been found with detritus such as license plates or pieces of old tires in its digestive tract. The Tiger shark is notorious for attacks on swimmers, divers and surfers in Hawaii; it is often referred to as the "bane of Hawaiian surfers".

Fierce Fish: The tiger shark is second only to the Great White in number of recorded human fatalities and is considered, along with the Great White, Bull Shark and the Oceanic Whitetip Shark to be one of the most dangerous to humans.

Stunning Shark: Its skin can typically range from a blue or green hue to light with a white or light yellow underbelly. The distinguishing dark spots and stripes are most outstanding in young sharks and fade as the shark matures. A tiger shark may weigh up to one ton (2,200 lb). It is usually three to five meters long (ten to sixteen feet), but some specimens have been up to seven meters long (twenty-three feet).

Just the Facts: Sexual maturity is reached at different stages for the sexes; males at 2.26 to 2.9 meters (7 to 9 feet) whereas females become mature at 2.5 to 3.25 meters (8 to 10 feet). It has been estimated that the tiger shark can swim at a maximum speed of around 32 km/h (20 mph), with short bursts of higher speeds that last only a few seconds.

Heads & Tails: The tiger shark's head is somewhat wedge-shaped, which makes it easy for the shark to turn quickly to one side. Tiger sharks have small pits on the side of their upper bodies which hold electrical sensors that enable them to pick up small muscle movements of other creatures, allowing them to hunt in darkness.

A Tiger shark generally has long fins and a long upper tail; the long fins act like wings and provide lift as the shark maneuvers through water, whereas the long tail provides bursts of speed. A tiger shark normally swims using lithe movements of its body. Its high back and dorsal fin act as a pivot, allowing it to spin quickly on its alliance.

Teeth for Turtles: Its teeth are flat, triangular, notched and serrated. Like most sharks, when a tiger shark loses or breaks one of its teeth, it grows a replacement tooth. The distinctive teeth seem to have evolved to be able to cut through turtle shells, and an adult tiger shark can easily bite through bone.

They Hunt at Night: The tiger shark, which generally hunts at night, has a reputation for eating anything it has access to, ignoring what nutritional value the prey may or may not hold. Apart from what is thought to be sparodic feeding, its most common foods include common fish, squid, birds, seals, other sharks, and sea turtles. The shark has a number of features which make it a good hunter, such as excellent eyesight, which allows for access to murkier waters which can offer varieties of prey and its acute sense of smell which enable it to react to faint traces of blood in its waters and is able to follow them to the source. The tiger sharks ability to pick up on low-frequency pressure waves produced by the movements of swimming animals, in a usual case, the thrashing of an injured animal, enables the shark to be introduced to a variety of prey.


Birds and Bees: The tiger shark breeds by internal fertilization. Like mammals, they give birth to live young. The male tiger shark will insert one of its pelvic fins into the females genital opening, acting as a guide for the sperm to be introduced. The male has been known to use its teeth to hold the female still during the procedure, often causing the female considerable discomfort. Mating in the northern hemisphere will generally take place between the months of March and May, with the young being born around April or June the following year. In the southern hemisphere, mating takes place in November, December, or early January.

The young are nourished inside the female body. This developmental period can go on for 9 to 16 months, where the female can spawn a litter ranging from 10 to 80 young. A new born tiger shark is generally 51 to 76 cm long and usually leaves its mother upon birth, since it has a full set of teeth and can hunt. It is unknown how long tiger sharks live, but has been speculated it is 20 years.

All text is available under the terms of the GNU Free Documentation License

   
 

 Kingdom: Animalia

 Phylum: Chordata

 Class: Chondrichthyes

 Order: Carcharhiniformes

 Family: Carcharhinidae

 Genus: Galeocerdo

 Species: Cuvier