Before we swim too deep into the serious issues facing this vulnerable species, studying the facts will create a better understanding.
REPRODUCTION: Great Whites’ young are called pups. While most species of sharks lay eggs, Great Whites give birth to 2-14 fully formed pups. When still inside the womb, they are nourished by eating smaller and weaker siblings and unfertilized eggs as they get no nourishment from a placenta. They are approximately 1.5m long when born and must fend for themselves as they are seen only as potential food by their mother.
DISTRIBUTION: Great Whites live in all temperate coastal waters, yet have been known to travel long distances; scientists are not certain if this is really migration. They can swim in water as shallow as 90cm (3 ft) and have been found as deep as 1280m (4200 ft). While generally restricted to coastlines, Great Whites can be found along the coasts of Eastern China to Russia, West Africa to Scandinavia, California to Alaska, Hawaii, the east coast of the USA, most of South America and the Gulf coast, Australia (except for the north coast), New Zealand, South Africa, Japan and the Mediterranean Sea.
DIET: Fortunately, humans are rarely found on Great White menus. Their favorite foods are seals and sea lions. They also eat large tuna, certain species of whales and dolphins, penguins and otters. Great Whites are not above scavenging for wounded animals and even dead fish lying on the top of the ocean surface.
CATCHING PREY: To catch their dinner, Great Whites cruise along the ocean floor and look for animals silhouetted above, against the light. If they see a shape that looks similar to a seal, they charge towards it full speed, grabbing it with their razor sharp teeth. South African Great Whites are unique in that they leap out of the water with their prey clutched in their jaws. They shake the prey to kill it faster. Once the prey has died, Great Whites tear chunks of flesh off the carcass and swallow it, without chewing.
APPEARENCE: The Great White shark is the biggest of all predatory sharks. With a grey top and a white belly, a Great White has the perfect camouflage. If looking from above, the grey top blends in with the murk of the sea floor and if look from the bottom, the white belly blends with the light sky above. They have three main fins, two pectoral (on either of the sides) and one dorsal fin (on the back). The tail has a slight crescent shape. There are five gill slits on each side of the shark.
TEETH: Great Whites can have about 3000 teeth at one time, arranged in several numerous rows. The first two rows of teeth are used for cutting and grabbing prey and the rest rotate into the place of teeth which have fallen out. New teeth grow constantly into the back of the mouth when teeth are lost.
SENSES: Sharks have extremely developed senses. Their primary sense is the sense of smell – they can smell one drop of blood in 100 liters (25 gallons) of water. The secondary sense is the ability to sense electrical charges in the water. They can sense charges as small as 0.005 micro volts. Prey can be detected by the electrical charge of a heartbeat or gill movement. Fish that are in hiding among the seaweed can be sensed out. Sharks also have an excellent sense of sight. Scientists have found taste buds lining the tongue and palate, indicating that sharks can taste foods as well. |