Facts: The Port Jackson Shark

The Port Jackson shark is a primitive bottom-dwelling shark species. They are from an ancient order of sharks. Port Jackson sharks primarily inhabit the temperate coastal waters along the southern half of Australia. They are often found aggregating close to reef structures. They are small sharks, less than 5.5 ft long. They have pronounced eyebrow ridges and a spine on each dorsal fin. They are nocturnal, feeding primarily on small invertebrates that are on or in the sediment, such as sea stars, sea urchins, and crabs. They also eat small fish. They grind food with their powerful jaws. The front teeth are small, sharp, and pointed for holding and breaking, while the back teeth are blunt and flat for crushing and grinding. They typically rest on the bottom during the day, often in caves. They can be solitary, but they frequently occur in small to large groups. Adults segregate into groups of They are oviparous, meaning that they lay eggs. The embryo is nourished by a large yolk mass. Male Port Jackson sharks mature between 8 and 10 years old, while females mature between 11 and 14 years old. Between July and October, males and females gather in large numbers to mate. A female lays a pair of spiral-shaped eggs every 10 to 14 days over a 3-month period. The embryo has an incubation period of 10 to 11 months. Females usually place the egg cases in rock crevices on shallow, sheltered reefs. A female can use her mouth to wedge the egg cases into the desired areas. The corkscrew designs of the egg cases serve as anchors to keep them wedged in the rocks. Crested horn sharks sometimes attack the eggs. For more marine facts, click the SUBSCRIBE button!!