Facts About Sand Tiger Shark

Sand tiger sharks derive their name from their habitat, which is mainly located towards the shoreline. These sharks have different names in different regions of the world. They are known as the gray nurse shark in Australia, the spotted ragged-tooth shark in Africa and the sand tiger shark in the United States and the United Kingdom. Even though, they have a threatening appearance, they are very gentle, slow-moving and do not attack humans, unless provoked. Let us know more about these beautiful creatures.

Physical Features

Sand tiger sharks have a stout body with a slightly flattened head. The snout is conical in shape and they have very small eyes. The mouth, which is kept open while swimming, is full of sharp-edged teeth. The dorsal fins are almost equal in size and are located far behind the gill slits. The upper lobe of the tail fin is longer than the lower one. They are grayish bronze in color with a pale white underside. Offspring of this shark, sport reddish brown spots on the tail and the posterior end of the body, which fade with age.

The length of an average sand tiger shark can range between 1.2 to 2.7 meters, but the longest specimen had a body length of 3.2 meters. These sharks weigh between 90 to 160 kilograms. One of the distinguishing features of this shark, is that they are the only known sharks, that surface to take in air. They store this air in the stomach, which helps them float.

Habitat and Distribution

Sand tiger sharks are found in all subtropical and tropical oceans. They can be seen in the eastern and western Atlantic, the Pacific and Indian Oceans and in the Mediterranean and Adriatic Seas. Their habitats include estuaries, bays, rocky coral reefs and sandy coastal waters. They are mainly found in coastal waters from the surf zone to the depth of 60 meters. They can also swim to the depth of over 200 meters and have a tendency to rest at the bottom.

Behavior and Food Habits

Sand tiger sharks remain calm and move slowly during the daytime, but become active in night. During the night, they move around in groups for predation. Their food includes small bony fish, crustaceans, squids, other sharks, crabs and lobsters. They are also known to attack full fishing nets.

Reproduction

The males reach maturity, when they measure a body length of 2.1 meters and females are able to reproduce when they are around 2.2 meters long. The female sharks give birth to two young ones after a gestation period of 9 to 12 months. These sharks are ovoviviparous, which means that they give birth to young ones from eggs, that hatch within the body. Female sand tiger sharks have two uteri. Many eggs hatch inside each of the uteri and the offspring feed on each other until only two are left i.e. one in each uterus. The mother shark produces eggs continuously, which provides nourishment to the young one in the uteri. They have a lengthy labor, usually in winter, and the young ones are almost one meter in length at birth. This method of reproduction is also termed as intrauterine cannibalism.

The lower reproduction rate among the sand tiger sharks has led to a decline in its population across the globe. These sharks are now a protected species in some countries like the U.S. and Australia. Conservation efforts are also underway to protect sand tiger sharks, which are the most popular sharks found in aquariums around the world.