The sand tiger shark is a relatively large species of shark that inhabits continental shelves and reefs to a depth of approximately 620 feet in subtropical and temperate waters worldwide. The diet of the sand tiger is composed mostly of bony fishes such as herrings, eels and bluefishes, among others. Crustaceans, squid and even smaller sharks are occasional prey.
Despite its namesake, the sand tiger is not closely related to the tiger shark. It instead is more closely related to the great white shark. It belongs to Lamniformes, the same order as the great white and mackerel sharks. The sand tiger, also known as the gray nurse shark or the spotted ragged-tooth shark, can reach approximately 10 feet in length and weigh up to 350 pounds. The conical head and jagged, protruding teeth of the sand tiger give it a fearsome appearance, although in reality this shark poses very little threat to humans due to its sluggish speed and general docility. The sand tiger is the only species of shark known to gulp air from the surface, which it stores in its stomach to assist in floating motionless through the ocean. A low reproductive rate has lead to this species being labeled vulnerable and protected.