For some people, the word shark is synonymous with fear, for others it stands for charisma and fascination. Great white sharks are extremely large and particularly beautiful, featuring unusual pigmentation, dark eyes, a built-in "grin" and an elegant swimming style.
Despite this wide distribution and its high profile, the great white shark has become rare in some areas of the world. In the Adriatic Sea (Mediterranean Sea) scientists estimate that great white numbers have declines over 80% in the last 130 years; in the northwest Atlantic they are thought to have declined almost 80% in numbers in the last 50 years! Other important declines have been observed in parts of South Africa and Australia.
By the way: The white sharks scientific name is Carcharodon carcharias . This comes from the Greek, karcharos = sharpen + Greek, odous = teeth
They "sniff out" their prey through a pair of nostrils that contain large numbers of small sensory organs called "lamellae". These little organs are connected directly to the centre of the brain and report every single interesting odour to the "headquarters". An even more powerful weapon in the white shark’s arsenal are the "ampullae of Lorenzini". Theses little jelly-filled canals are sensitive to very small electrical fields. No matter how big or small a prey is – with the built-in electrical field detection system a great white shark can track it down. And more than that: every animal produces different sets of electrical information depending on its activities e.g. if it is swimming peacefully or moving in an unusual way because it is in distress or wounded. White sharks, the "high-tech-predators", can distinguish between the different patterns.
But not only its senses are high-tech. The torpedo-shape of this charismatic fish is evolution at its best. From the conical snout to the symmetrical tail and the sharp dorsal fin – every single part of its body contributes to its great success as an apex predator. Even the skin of sharks is unique and served as a model for swim suits that provided professional swimmers with the head start of valuable seconds. It is living bionics!
A Real Cosmopolite
Due to its powerful swimming capabilities and its ability to maintain a body temperature up to 15 °C warmer than the water temperature this charismatic predator is among the most widely distributed of sharks. Great white sharks have been observed along the coastlines of Baja California to Alaska, the east coast of the USA, the Caribbean and most of the Gulf of Mexico coast, Hawaii, South America, South Africa, Australia, New Zealand, the Mediterranean Sea, West Africa to the Gulf of Gascoigne, Japan, eastern China and southern Russia. They are real cosmopolites!Despite this wide distribution and its high profile, the great white shark has become rare in some areas of the world. In the Adriatic Sea (Mediterranean Sea) scientists estimate that great white numbers have declines over 80% in the last 130 years; in the northwest Atlantic they are thought to have declined almost 80% in numbers in the last 50 years! Other important declines have been observed in parts of South Africa and Australia.
Impressive Profile
Let´s face it: This fish can become really huge. It grows up to nearly 7 meters and can weigh more than 3 tons. On average white sharks are between 3.5 and 5 meters long. As with most sharks, females are larger than males. Its teeth are sharp as a knife – several rows of over 50 triangular, saw-edged teeth arm its mouth. They are located in rows which slide into use as needed and replace teeth when they are lost, broken or worn down. Enviable!By the way: The white sharks scientific name is Carcharodon carcharias . This comes from the Greek, karcharos = sharpen + Greek, odous = teeth
Fast Swimmers but Slow Reproducers
Great white sharks swim and hunt with impressive speed. But there are a few things they don´t do fast: growing and reproducing. And that is their doom - their slow growth rates and late age of sexual maturation makes them extremely vulnerable to exploitation. It is estimated that a female great white matures sexually at 12-18 years of age. A long time to survive in heavily fished oceans! They reproduce using ovoviviparity which means that fertilization of the eggs occurs within the female through copulation, and the eggs are hatched in the womb where the embryos continue to grow. There is no placenta to nourish the baby great whites, but they feed upon unfertilized eggs that the mother continues to produce throughout gestation– even before birth they must fend for themselves. After a period believed to be of 12-18 months females give birth to only 2-10 fully-formed pups that are up to 1.5 m long.Not very picky
The great white shark is what we call an apex predator: the top of the food chain with no natural enemies, at least in the majority of the places where it occurs. While in some areas of the world adult great whites feed greatly on seals, sea lions, and other marine mammals the king of the oceans seems not to be particularly picky when it comes to food. A large variety of fish, squid and other invertebrates, and even other sharks, are also part of its menu. White sharks also feed on carcasses, especially those of large whales. They have one bad habit our moms would never tolerate: they do not chew their food! They rip their prey into mouth-sized pieces and swallow them whole.Great Whites are Stalkers
Although it is called the great WHITE shark, only the underbelly is actually white, the top surface is dark grey to brownish grey. This coloration is extremely useful when hunting prey because this giant strikes from below and its dark back blends with the water enabling it to approach the prey unobserved. It is the perfect camouflage when preying upon seals and sea lions. Typically, a great white stalks them from near the rocky bottom – almost invisible – and attacks in a sudden vertical rush often leaping out of the water.Evolution at its best: The High-Tech Predator
Great whites are real high-tech-animals. They are equipped with two very powerful sensing mechanisms: The ability to sense the electrical fields all living creatures generate and an extremely developed sense of smell.They "sniff out" their prey through a pair of nostrils that contain large numbers of small sensory organs called "lamellae". These little organs are connected directly to the centre of the brain and report every single interesting odour to the "headquarters". An even more powerful weapon in the white shark’s arsenal are the "ampullae of Lorenzini". Theses little jelly-filled canals are sensitive to very small electrical fields. No matter how big or small a prey is – with the built-in electrical field detection system a great white shark can track it down. And more than that: every animal produces different sets of electrical information depending on its activities e.g. if it is swimming peacefully or moving in an unusual way because it is in distress or wounded. White sharks, the "high-tech-predators", can distinguish between the different patterns.
But not only its senses are high-tech. The torpedo-shape of this charismatic fish is evolution at its best. From the conical snout to the symmetrical tail and the sharp dorsal fin – every single part of its body contributes to its great success as an apex predator. Even the skin of sharks is unique and served as a model for swim suits that provided professional swimmers with the head start of valuable seconds. It is living bionics!
Curious Guys
White sharks are highly curious and exploratory, they often investigate novel objects in their environment. First they check things out visually and, if nothing too frightening happens, eventually they go for a small, gentle "test-bite". Unfortunately this habit can prove quite disadvantageous for humans... Another unusual habit: They will swim to the surface and poke their heads up out of the water. No one knows exactly why it does this; perhaps to observe activities above the surface.
