port jackson shark Australian sharks have a small blunt head. have unique teeth
Port Jackson sharks (Heterodontus portusjacksoni) are found in the depths of the Pacific Ocean in Australia.
They belong to the family Heterodontidae and are oviparous in nature. They can be found in different colors like fawn, light brown, grayish-white, or completely white.
They mostly feed on crustaceans and mollusks and are also known as oyster crushers as well. The embryo of these species is hunted down by other shark species.
They are predatory in nature but do not pose any threat to human beings. The Port Jackson shark has its native habitat in temperate South Australian waters.
They are known to swim across southern Queensland, Tasmania, and then towards the central coast of Western Australia.
The scientific name for the horn shark is Heterondontus francisci which derives from the Greek word heteros, meaning different; and odont, meaning teeth.
Port Jackson sharks are bull-headed sharks that are gray, white, fawn, or light brown in color. The head is blunt and the mouth is small.
Their sides and back are covered in prominent bands of black. Crests are also seen above the Port Jackson shark’s eye.
These Australian sea sharks have spiny dorsal fins and an anal fin is present as well.
The body of a Port Jackson shark is elongated and it is considered to be the largest shark in the group of bull-headed sharks.
The Port Jackson shark is the largest shark in the group of bullheaded sharks.
The average length of a male Port Jackson shark is 3.11 ft and they are 13.2 lb in weight while the females are longer and have an average body length of 3.34 ft and weigh between 31-35 lb.
Sexual dimorphism is very evident, with females being twice the size of a male port Jackson shark.
The female port Jackson sharks have a body mass of 31-35 lb, while the males weigh from 13.2-22 lb. The females are longer and heavier than the males, displaying sexual dimorphism.
Port Jackson sharks mostly feed on sea urchins, mollusks, crustaceans, and other small fish species. The shell of the crustaceans is first crushed by the port Jackson shark and then the mass is swallowed.
Like all other sharks, Port Jackson sharks do not chew their prey but swallow them whole. They forage during the night when their prey is most active.
They also suck sand to catch their prey and blow it out from their gills. The juveniles feed on more soft-bodied prey than the adults.
Port Jackson sharks’ habitat is deep, temperate waters with rocky environments.
It is a bottom-dwelling shark that is also sometimes found near the shore. Sandy and muddy habitats can also be used by the Port Jackson shark.
These sharks can be found from southern coastal Australia to the central coast of Western Australia. Some species have also been found as far north as York Sound in Western Australia.
The male port Jackson sharks achieve sexual maturity at the age of around 10 years old, while the females attain sexual maturity at the age of 11-14 years old.
The manner of reproduction is oviparous, which means that the females give birth to live juvenile sharks after the eggs hatch inside the body.
An annual reproductive cycle is seen in port Jackson sharks. The breeding season lasts from the month of August to the second week of November.
After mating, the female gives birth to pairs of eggs every 10 days. The average clutch size is 16 eggs.
The mother moves the soft-shelled eggs to rock crevices or depressions, where it incubates for the next 10-12 months.
The Port Jackson shark is the largest species of Heterodontus shark. It has an average lifespan of 30 years in captivity. Some specimens of the Port Jackson shark have lived for more than 30 years.
Ref: australian.museum, wikipedia, abyss, kidadl, floridamuseum, sharksandrays
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