Carcharhinus leucas Zambesi Bull Shark's Tooth (1) Dogfishes Cartilaginous Fishes Chondrichthyes Selachians Elasmobranchs Carcharinidae

Description

Origin : Indian Ocean (Madagascar)

Size : mm 20-25

Carcharhinus leucas (Müller and Henle, 1839) or Zambesi Shark, not to be confused with the Bull Shark (Carcharias taurus) because the "bull shark nomenclature" attributed to it in English-speaking countries, is a kind of family Carcharinidae widespread in warm, shallow waters of coastal areas and rivers from all over the world and moves over large distances. It goes up to 150 meters deep, but generally does not drop more than 30 meters.

It is best known for his unpredictable behavior and often aggressive. Since it is often found in shallow water, it is considered the most dangerous species of shark for man, and together with the tiger shark and the white shark, is one of three species to which have been attributed the highest number of attacks to ' man unless you consider the Carcharhinus longimanus, which alone has more attacks of all those of other sharks put together.
Unlike most sharks, this shark tolerate fresh water and is able to trace the course of the rivers and rapids up to the lakes, such as salmon, employing about a dozen days to make the journey. Some specimens have been found even in some rivers of Australia, southern Africa, and North America.
Precisely for this reason the species is probably responsible for more attacks to humans occurred in coastal waters, including many attacks attributed to other species. However C. leucas sharks (unlike the kind river Glyphis sharks) are not true freshwater sharks. It is the best known among the 43 species of elasmobranchs spotted in fresh water. Their ability to enter into fresh water is rather limited, since their blood is salty (in terms of osmotic strength) because the water of the sea, due to the accumulation in the tissues of urea and trimethylamine oxide, but the C. leucas that live in fresh water are able to reduce the concentration of these solutes of up to 50%.
The name "bullshark", used exclusively in English-speaking countries, is derived from the squat form of this species, the short and flattened and his unpredictable behavior and aggressive snout. In India this shark is often confused with the Ganges shark. In Africa is commonly called the Zambezi shark or simply zambi. Its range very wide and the variety of environments in which they live are reflected in the many local names with which is known as whaling shark, shark of Lake Nicaragua, the river shark, freshwater shark, Swan shark, shark and puppy shark-nosed shovel.
The C. leucas are big and stocky. Females are larger than males. They can reach 3.5 meters in length and a weight of 230 kilograms. They are heavier than others Carcharinide of equal length. The coloring is gray on the back and white on the belly.
Much of their diet consists of bony fish and smaller sharks, including other members of their species. However, they can feed themselves, even of turtles, birds, dolphins, land mammals, crustaceans and echinoderms. To attack their prey species using the "hit-and-bite technique." relatively calm specimens have suddenly become violent and started to hit divers.
The C. leucas are usually solitary predators, but every so often hunt in pairs. They are often spotted as they patrol the shallow waters. Specimens in peaceful appearance can suddenly increase speed and become extremely aggressive: a specimen has even attacked a thoroughbred racing in an Australian river. They are very territorial and will attack any animal that enters their territory.
C. leucas mate in late summer and early autumn, often in brackish water of river mouths. After a gestation period of 12 months the female gives birth to live young 4-10: the species, ie, viviparous. The small, 70 cm long at birth, it will take 10 years to reach maturity.
Recently it was discovered that in some cases these sharks practice the so-called "uterine cannibalism"; in these cases, only a small can survive the pregnancy.
Thia shark is an apex predator and only rarely attacked by other animals. Their only real enemy is man. Nevertheless, some larger sharks such as the tiger shark and the great white shark, are able to attack him. They are also well-documented cases of marine crocodiles that regularly prey on this species in the rivers and estuaries in Northern Australia. Also probably another big Crocodilidae, as the Nile crocodile and the American crocodile (which share some parts of their range with the C. shark) show a similar predatory behavior.