The tiger shark, scientifically known as Galeocerdo cuvier, belongs to the order Carcharhiniformes, which encompasses a diverse range of shark species. It is the sole extant member of the genus Galeocerdo and the family Galeocerdonidae. The species was first described by Peron and Lesueur in 1822 and later renamed by Müller and Henle in 1837 as Galeocerdo tigrinus. Its name is derived from the Greek words "galeos" (shark) and "kerdo" (fox), alluding to its unique characteristics.
The evolutionary history of the tiger shark extends back to the Eocene epoch, with the oldest remains dating to this period. Fossil records of the modern tiger shark, Galeocerdo cuvier, can be traced back approximately 13.8 million years to the Middle Miocene.
Tiger sharks are impressive creatures, with adult lengths ranging from 3.25 to 4.25 meters (10 ft 8 in – 13 ft 11 in) and weights varying between 175 and 635 kilograms (386 to 1,400 lb). Females tend to be larger than males, reaching lengths over 3.7 meters (12 ft 2 in), while mature males rarely surpass this size. Exceptionally large females have been reported measuring over 5 meters (16 ft 5 in) and weighing more than 900 kilograms (2,000 lb).
The distinctive teeth of tiger sharks are characterized by sharp, pronounced serrations and a sideways-pointing tip. These teeth are specialized for slicing through various prey, including flesh, bone, and even turtle shells. Tiger sharks possess multiple rows of teeth, which are continually replaced throughout their lifetime.
The tiger shark's body features long fins that provide lift during swimming, while its elongated upper tail enables bursts of speed. With small body movements, these sharks expertly navigate through water.
The tiger shark is renowned for having one of the broadest food spectrums among all shark species. Its diet encompasses a vast range of prey, including crustaceans, fish, seals, birds, squid, turtles, sea snakes, dolphins, and even other smaller sharks. This versatile feeding behavior has led to its colloquial title as a "garbage eater." Tiger sharks exhibit a remarkable ability to consume inedible objects, including man-made debris that lingers in their stomachs.
Tiger sharks inhabit tropical and subtropical waters worldwide, often found in close proximity to coastlines. Their behavior is primarily nomadic, guided by warmer ocean currents and seasonal variations. While they prefer deep waters along reefs, tiger sharks also venture into shallower channels in pursuit of prey.
These formidable creatures have been spotted in various locations, including the Gulf of Mexico, North American beaches, South America, the Caribbean Sea, Africa, China, India, Australia, and Indonesia. They can tolerate depths of nearly 900 meters (3,000 ft), and some individuals have even been recorded in the Mediterranean Sea, albeit rarely.
Males typically reach sexual maturity at lengths between 2.3 and 2.9 meters (7.5 to 9.5 ft), while females mature at lengths of 2.5 to 3.5 meters (8.2 to 11.5 ft). Female tiger sharks mate once every three years, engaging in internal fertilization. During mating, males employ specialized claspers to guide sperm into the female's cloaca.
The gestation period of tiger sharks lasts approximately 16 months, with litters ranging from 10 to 80 pups. At birth, tiger shark pups measure between 51 and 76 centimeters (20 to 30 in) in length. Remarkably, tiger sharks employ embrytrophy to nourish their young inside the womb. This unique adaptation allows the embryos to develop within fluid-filled sacs, facilitating substantial growth without a direct placental connection to the mother.
The tiger shark is classified as a near threatened species due to human activities such as finning and overfishing. It faces the risk of population decline and habitat loss. Conservation efforts, including sustainable fishing practices and marine protected areas, are crucial for the long-term survival of this magnificent predator.