Port Jackson Shark
Heterodontus portusjacksoniBiology
The Port Jackson shark, a sleeper shark, is a nocturnal predator that mainly feeds on bottom-dwelling invertebrates like sea urchins, sea stars, crabs and shellfish whose shells it crushes with its flattened, molar-like teeth.
It can be recognized by its massive head and characteristic piggish snout. Its particularly large nostrils provide for maximum sensory contact. To defend itself, it has a sharp spine in front of each dorsal fin that it can plant in the mouth of an attacker, who will instantly release it.
Reproduction
During the breeding season, this shark undertakes major migrations.
The females may cover more than 800 kilometres to reach their nesting site.
They then deposit their eggs, shaped like spiral capsules, in the shallow waters. After a year of incubation, the 25 cm young emerge from the eggs and travel to sheltered areas in bays or estuaries.
Respiration
Although most sharks need to swim constantly in order to breathe, the Port Jackson shark can actively pump seawater while resting on the ocean floor.
It can even separate its feeding and respiratory functions: the water enters the first gill slit and exits the next four without ever passing through its mouth.
This shark is endemic to the coastal waters of Australia, and to Port Jackson in particular, Sydney's natural harbour and home to its famous opera house.
