Bull shark

Bull sharks are found worldwide in tropical and warm temperate waters including coastal seas, estuaries and rivers to depths of at least 150 m.

In Australia, they occur in tropical northern and warm temperate waters and are relatively common on the East Coast of Australia north of Sydney.

Within WA, adult bull sharks occur in marine waters throughout the Kimberley region, and juveniles are common in tropical river systems, including the Fitzroy River. It is unclear how common the species is south of Broome. Due to the lack of permanent freshwater rivers through most of the Pilbara and Gascoyne coastline, there appears to be limited suitable nursery habitats.

In south-west Western Australia, they are found in Perth’s Swan and Canning rivers and have also been reported in a number of other South West rivers and estuaries, including the Collie River.

Research is ongoing to better understand the abundance and distribution of this species in Western Australia.

Bull sharks are viviparous, meaning they give birth to live young. In Eastern Australia, females mature at around 230 cm and males around 220 cm (both at approximately 10 years of age).

Females give birth to litters ranging from 1-13 pups at 55-80 cm. They birth (‘pup’) in estuaries and rivers, where pups are protected from large predators and remain for several years.

Bull sharks are known for their aggressive behaviour and are considered potentially dangerous. Their presence in rivers and estuaries often brings them into close proximity with humans, and they have been involved in human interactions in New South Wales, Queensland, and Western Australia.

They are not commonly caught south of the Kimberley due to low numbers. Juveniles may be caught occasionally by recreational and commercial fishers in the Swan and Canning Rivers.