GREAT WHITE SHARK (Carcharodon Carcharias)......!!
The Great White Shark is a macropredator found mainly in temperate seas and oceans, but the Great White Shark can also occasionally enter tropical waters. It is principally an epipelagic dweller, which means that it can typically be found in the uppermost layers of the ocean; normally between the ocean surface and the thermocline at a depth of roughly 200 meters. The Great White Shark is however known to sometimes venture as far down as 250 meters. It can be found at the surfline as well as in waters very far from the shore. The Great White Shark is found of coastal archipelagos where deep water and shallow shores are located close to each other, and offshore fish reefs can be found.
Great White Sharks are actually not only white. Above, their colours vary from nearly black to grey while the ventral surfaces are white or whitish. The pelvic fins can be spotted with olive and grey. In strong sun-light, the lateral surfaces can show off an almost bronze coloured sheen. The areas around the gill-slits and over the pelvic fin bases are often blotched. It is also common with small, irregular black or dark spots on the flanks posterior to the fifth gill slit. Each Great White Shark has an individual colouration and pattern, but there are also regional similarities.
For example, Great White Sharks outside Cape Province in South Africa typically show more olive shades, while Great White Sharks outside California in the U.S. have a very dark slate-grey colouration. Great White Sharks in the Mediterranean Sea are usually olive-brown or slate-grey.
There has always been a lot of speculation regarding the maximum size of a Great White Shark. Unconfirmed sources claim that a female Great White Shark longer than 7 metres was seen outside Kangarro Island in Australia in 1987. The same year, a female shark from Malta was reported as 713 centimetres. In October 1998 a photograph of this shark was however examined and the shark turned out to be no longer than around 530 centimetres.
Most experts believe that the maximum length of Great White Sharks is somewhere around 6 metres. The smallest adult Great White Sharks found in the wild are around 120 centimetres. We still do not know for sure the lengths at maturity for the Great White Shark, and it is possible that different populations reach maturity at different lengths. We do however know that female Great White Sharks frequently mature when they are between 450 and 500 centimetres, and that male Great White Sharks often mature when they are around 350 centimetres.
A study on 21 Great White Sharks showed that they matured when they were approximately 10-12 years old, but this was just a single study on quite a few individuals and can not be used to make any generalised assumptions.
For example, Great White Sharks outside Cape Province in South Africa typically show more olive shades, while Great White Sharks outside California in the U.S. have a very dark slate-grey colouration. Great White Sharks in the Mediterranean Sea are usually olive-brown or slate-grey.
There has always been a lot of speculation regarding the maximum size of a Great White Shark. Unconfirmed sources claim that a female Great White Shark longer than 7 metres was seen outside Kangarro Island in Australia in 1987. The same year, a female shark from Malta was reported as 713 centimetres. In October 1998 a photograph of this shark was however examined and the shark turned out to be no longer than around 530 centimetres.
Most experts believe that the maximum length of Great White Sharks is somewhere around 6 metres. The smallest adult Great White Sharks found in the wild are around 120 centimetres. We still do not know for sure the lengths at maturity for the Great White Shark, and it is possible that different populations reach maturity at different lengths. We do however know that female Great White Sharks frequently mature when they are between 450 and 500 centimetres, and that male Great White Sharks often mature when they are around 350 centimetres.
A study on 21 Great White Sharks showed that they matured when they were approximately 10-12 years old, but this was just a single study on quite a few individuals and can not be used to make any generalised assumptions.
The Great White Shark has a conical snout, with a rather blunt shape. The teeth are large, shaped like triangles and coarsely placed in a saw-like pattern. Their Latin name, Carcharodon carcharias, actually means the 'Jagged-Toothed One'. The Great White Shark is equipped with five large gill-slits.
The characteristic first dorsal fin is almost an equilateral triangle, with a somewhat concave rear margin. In very young individuals, the first dorsal fin is rounded at the apex, and grows pointier during the first two years. The second dorsal fin is always extremely small in Great White Sharks. The caudal fin is crescent-shaped, and in Great White Sharks larger than 2.0 meters it usually has an acutely pointed tip. In newborn sharks, the lower caudal surfaces are generally more compressed and rounded. These areas will however expand rapidly after birth and soon look like the caudal surfaces of an adult Great White Shark.
The Great White Shark belongs to the genus Carcharodon and its closest known relatives are four other Mackerel sharks in the family Lamnidae. Most historians agree that when Aristotle and other Greek writers wrote about the “the fearsome Lamia monster” they were referring to the animal that we today call the Great White Shark. The name Lamia and Lamie is still used in several Mediterranean languages, such as Greece and languages from southern France.
During the 16th century naturalist Guillaume Rondelet suggested that maybe the prophet Jonah in the Bible was not swallowed by a whale, but by a Great White Shark. Just like today, the Great White Shark was both feared and admired and surrounded by a lot of rumours. Historically, the Great White Shark has been known under several different names. There has always only been one recognized white shark species, but is has been called Squalus carcharias, Carcharias lamia, Carcharias verus, Carcharodon rondeletii, Squalus carcharias and Carcharodon smithii. Today, the formal Latin name is Carcharodon carcharias, which means the Jagged-Toothed One.
The characteristic first dorsal fin is almost an equilateral triangle, with a somewhat concave rear margin. In very young individuals, the first dorsal fin is rounded at the apex, and grows pointier during the first two years. The second dorsal fin is always extremely small in Great White Sharks. The caudal fin is crescent-shaped, and in Great White Sharks larger than 2.0 meters it usually has an acutely pointed tip. In newborn sharks, the lower caudal surfaces are generally more compressed and rounded. These areas will however expand rapidly after birth and soon look like the caudal surfaces of an adult Great White Shark.
The Great White Shark belongs to the genus Carcharodon and its closest known relatives are four other Mackerel sharks in the family Lamnidae. Most historians agree that when Aristotle and other Greek writers wrote about the “the fearsome Lamia monster” they were referring to the animal that we today call the Great White Shark. The name Lamia and Lamie is still used in several Mediterranean languages, such as Greece and languages from southern France.
During the 16th century naturalist Guillaume Rondelet suggested that maybe the prophet Jonah in the Bible was not swallowed by a whale, but by a Great White Shark. Just like today, the Great White Shark was both feared and admired and surrounded by a lot of rumours. Historically, the Great White Shark has been known under several different names. There has always only been one recognized white shark species, but is has been called Squalus carcharias, Carcharias lamia, Carcharias verus, Carcharodon rondeletii, Squalus carcharias and Carcharodon smithii. Today, the formal Latin name is Carcharodon carcharias, which means the Jagged-Toothed One.
Detailed knowledge about the reproductive habits of the Great White Shark is scarce, but has at least improved greatly during recent years. Earlier, most of the ideas and suggestions regarding the Great White Shark's reproduction were based on comparisons with other related shark species that were more well-known to the scientific community.
There is one report from 1937 about the capture of a pregnant shark three years earlier, but it is not sure whether this was a Great White Shark or some other species. It wasn’t until the 1980’s that more detailed studies of pregnant Great White Sharks took place. Verified reports talk about 5 to 10 embryos, but there are also unconfirmed reports about 14 embryos. The female shark develops no placenta, and the embryos are instead nourished by ingestion of unfertilised eggs (oophagy).
The embryos also swallow their own shed teeth; probably to re-utilise calcium and other minerals but this has still not been confirmed. The gestation time is not known, but estimated to be around 12 months. The birth probably takes place in temperate shelf waters from spring to late summer. A new born Great White Shark is between 120 and 150 centimetres.
There is one report from 1937 about the capture of a pregnant shark three years earlier, but it is not sure whether this was a Great White Shark or some other species. It wasn’t until the 1980’s that more detailed studies of pregnant Great White Sharks took place. Verified reports talk about 5 to 10 embryos, but there are also unconfirmed reports about 14 embryos. The female shark develops no placenta, and the embryos are instead nourished by ingestion of unfertilised eggs (oophagy).
The embryos also swallow their own shed teeth; probably to re-utilise calcium and other minerals but this has still not been confirmed. The gestation time is not known, but estimated to be around 12 months. The birth probably takes place in temperate shelf waters from spring to late summer. A new born Great White Shark is between 120 and 150 centimetres.
The actual copulation has not been witnessed, but curious surface behaviour performed by Great White Sharks that might be a part of the mating ritual has been observed. The mating rituals for other species of sharks often include biting and grasping with the teeth, and bite marks have been found on the pectoral fins, the flanks and the dorsum of female Great White Sharks which indicates that this might be a part of their mating ritual as well.
Large adult Great White Sharks of both sexes and their offspring have been sighted together in particular regions around the world, which probably means that these areas are the nursing grounds for Great White Sharks. Examples of such areas are the waters around Japan, Southern and Eastern Australia, New Zeeland, the Eastern Cape Province of South Africa, Southern California and Baha in the U.S. and the Southern-Central Mediterranean Sea (particularly between Tunisia and Western Sicily). Somewhat older Great White Sharks, but still aged less than one year, have been caught outside Algeria, North Aegean and France in the Mediterranean.
Large adult Great White Sharks of both sexes and their offspring have been sighted together in particular regions around the world, which probably means that these areas are the nursing grounds for Great White Sharks. Examples of such areas are the waters around Japan, Southern and Eastern Australia, New Zeeland, the Eastern Cape Province of South Africa, Southern California and Baha in the U.S. and the Southern-Central Mediterranean Sea (particularly between Tunisia and Western Sicily). Somewhat older Great White Sharks, but still aged less than one year, have been caught outside Algeria, North Aegean and France in the Mediterranean.
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