Marine Mammals
Neophoca cinerea
Australia’s only endemic pinniped, the Australian sea lion occurs along the coasts and offshore islands of South Australia and southern Western Australia. It is a highly specialised marine predator with an unusual breeding cycle and strong connections to individual breeding colonies.
australian sea lion
Scientific Name
Neophoca cinerea
Family
Otariidae
Conservation Status
Endangered — EPBC Act
Distribution
South Australia & Western Australia
Feeding
Benthic predator
ECOLOGY
Australian sea lions forage across continental-shelf habitats, diving to the seafloor in search of prey including fish, octopus, cuttlefish, rays and other marine animals.
Unlike many marine predators, individuals can develop highly specialised foraging strategies, using different behaviours depending on habitat and prey.
Image: Gergo Rugli
A SPECIALISED BENTHIC PREDATOR
DISTRIBUTION & HABITAT
Where Australian Sea Lions Live
Australian sea lions breed at colonies scattered along the southern and western Australian coastline, often on remote islands and isolated stretches of coast.
Females show exceptionally strong natal-site fidelity, generally returning to the colony where they were born to reproduce. This creates relatively isolated breeding populations and limits the ability of colonies to recover if numbers decline.
Life History
Breeding & Pup Development
The Australian sea lion has one of the most unusual reproductive cycles of any pinniped. Colonies breed asynchronously, meaning breeding does not occur at the same time across the species’ range.
Females produce relatively few pups over their lifetime, with a gestation period lasting up to 14 months, contributing to the species’ slow capacity for population recovery.
Identification
Sea Lion or Fur Seal?
Australian Sea Lions have three visual identifiers:
Australian sea lions belong to the eared-seal family, Otariidae. They can be distinguished from true seals by their visible external ear flaps and their ability to rotate their hind flippers beneath their body, allowing them to move more easily on land.
Image(s): Gergo Rugli
External ear flaps
Large Front Flippers
Body Colour
Research
Researchers from the University of Adelaide and SARDI Aquatic Sciences have used animal-borne cameras and sensors to investigate where Australian sea lions forage and how they hunt.
The footage has revealed sea lions moving through seagrass meadows, sand plains, sponge gardens and rocky reefs, using strategies including ambush hunting, chasing prey and overturning rocks.
Seeing the reef through a sea lions eyes
Conservation
Population Decline & Threats
Historic commercial sealing caused severe declines in Australian sea lion populations, and the species has not recovered to its former abundance.
Research indicates populations have declined by more than 60% over the past four decades. Contemporary pressures include interactions with fisheries, marine debris, disease, habitat change and other local threats.
Avian Influenza (Bird Flu)
Australian sea lions are also vulnerable to avian influenza (bird flu), which can affect marine mammals as well as birds. Gathering in colonies can increase the risk of disease spreading, while their small population and slow breeding cycle make recovery from losses particularly difficult. These factors place Australian sea lions at very high risk from H5 bird flu. Close monitoring and early detection, alongside efforts to reduce other threats, remain important in protecting this endangered species.
Update, 16 September 2026: H5 bird flu has been confirmed in an Australian sea lion at Seal Bay, Kangaroo Island. Wildlife authorities continue to monitor the situation. See the South Australian Government’s updates for the latest information.
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BOTTLENOSE DOLPHIN (Tursiops truncatus)
Bottlenose dolphins occur in coastal and offshore waters and are highly social predators with complex behaviours and social structures. Image: Gergo Rugli
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SOUTHERN RIGHT WHALE (Eubalaena australis)
Southern right whales migrate into southern Australian coastal waters during winter and spring, using sheltered bays and coastlines for breeding and calving.
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