Port Jackson Shark Egg. Warmer water temperatures result in shorter incubation periods, while colder water temperatures result in longer incubation periods The Port Jackson shark (Heterodontus portusjacksoni) is a nocturnal, oviparous (egg laying) type of bullhead shark of the family Heterodontidae, found in the coastal region of southern Australia, including the waters off Port Jackson.It has a large, blunt head with prominent forehead ridges and dark brown harness-like markings on a lighter grey-brown body, and can grow up to 1.65 metres (5.5.
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Port Jackson sharks are oviparous, meaning they lay egg capsules instead of giving live birth, and have an annual reproductive cycle And there's practical reasons for its bizarre shape
The Port Jackson shark breeding season lasts from late August to mid November, during which time a female will lay a pair of eggs every 10-14 days. The Port Jackson shark breeding season lasts from late August to mid November, during which time a female will lay a pair of eggs every 10-14 days. The incubation period for Port Jackson shark eggs ranges from 10 to 11 months, depending on the water temperature
. PJS's deposit their egg cases in very shallow water, often less than 5m deep Port Jackson Sharks are oviparous, which means that the female lays eggs
. Like other heterodontids, the Port Jackson shark lays auger shaped egg cases.( they lay two eggs every 10 to 14 days, for a total of 8-16 eggs per year ) PJS's deposit their egg cases in very shallow water, often less than 5m deep