NAME: Port Jackson Shark
SCIENTIFIC NAME: Heterodontus portusjacksoni
STATUS: Least Concern

​

POPULATION DECLINE: The Port Jackson Shark is an Aussie icon, found only in the waters of southern Australia. These small to medium-sized bottom-dwelling sharks love to tuck themselves away under rocks and in lush kelp forests. With their beautiful grey-to-light-brown colouring and bold black ‘harness’ stripes across their bodies and eyes, they’re instantly recognisable. Part of the bullhead shark family (Heterodontiformes), they get their name from Port Jackson, the inlet that holds Sydney Harbour, where they were first documented.

​

SIZE: Eggcase: 13-17 x 5-7cm (at broad end) At birth: 23-24cm. Mature males: 70-80cm. Mature females: 80-95cm. Max size: 165cm

​

RANGE AND HABITAT: These temperate water sharks call southern Australia’s rocky and kelp-covered coastlines home. As summer approaches, some adult females migrate up to 800km south to Tasmania, returning to warmer continental waters in autumn.

Found in temperate waters from the intertidal zone down to at least 275m, these sharks prefer sandy floors beside rocky reefs, as well as caves and gullies. Females lay pairs of corkscrew-shaped eggs every one to two weeks, usually on shallow rocky reefs around 5m deep. They can produce up to eight pairs in a season, with the yolk sac taking up most of the space inside the egg.

​

DIET: Port Jackson Sharks eat a diet of urchins, crustaceans, molluscs or small fish.

​

BEHAVIOUR: Port Jackson Sharks are mostly nocturnal, spending their days resting on their large pectoral fins. They’re often spotted in groups or lounging near their favourite caves and gullies. Port Jackson sharks gather in large numbers in shallow waters during late spring to mate. Males arrive first, with females following weeks later. Mating is a rough affair, with males biting onto the female’s fins or flank to roll her over.

Once the breeding season ends, males head into deeper waters, followed by females after laying their eggs. While females may travel as far as Tasmania, where the males go remains a mystery. Year after year, these sharks complete their epic migration, returning to shallow coastal bays to breed.

​

BIOLOGY:  

- Port Jackson Sharks are oviparous, meaning they reproduce by laying eggs. Females lay 10-16 eggs in pairs every 8-17 days, mostly between August and September. Their distinctive corkscrew shape helps secure them in rocky crevices on sheltered reefs, keeping them safe from predators. Packed with protein, these eggs are a sought-after snack, not just for other sharks, but even for fellow Port Jackson Sharks!
- Gestation: Lasts 10 months
Sexual Maturity: Males mature at 8-10 years, females at 11-14 years. Females may breed annually or every other year.
-  Lifespan: they live up to 28 years

​

THREATS: Port Jackson Sharks are thriving! Though often caught as bycatch, they hold no value as food and are usually released alive - a win for sharks!