Great White Sharks in Australia: A Diver's Guide

A great white shark does not so much arrive as appear. One moment the water off the Neptune Islands is an empty column of blue; the next, a grey and white body several metres long is sliding past the cage bars, a black eye turning to take you in. Few encounters in Australian diving carry the same weight, and few animals come wrapped in as much myth.

For divers, the white shark (*Carcharodon carcharias*) sits in an awkward place. It is responsible for more recorded shark bites in Australia than any other species, yet it is protected, slow to recover from losses and surprisingly hard to see on purpose. This is what the research, the national shark-bite records and the people who run Australia's only white shark cage dives actually tell us.

Where white sharks live in Australian waters

CSIRO describes white sharks as living in coastal, shelf and continental slope waters from the Montebello Islands in north-western Western Australia, south and around the southern coastline (including Tasmania) to central Queensland. Tagged sharks show a pattern of temporary residency at favoured sites broken up by long-distance travel, including crossings to New Zealand and between Western Australia and South Africa. They are not permanent residents of any one site.

Genetic and tracking studies split Australian white sharks into two populations either side of Bass Strait: an eastern population whose range extends across to New Zealand, and a southern-western population from western Victoria to north-western Western Australia. Using a close-kin genetic method, CSIRO estimated about 750 adults in the eastern population (range 470-1,030) and about 1,460 adults in the southern-western population (range 760-2,250). CSIRO has also identified two juvenile nursery areas on the east coast, and its researchers have tagged juveniles off Port Stephens in NSW.

Size and biology

The Australian Museum lists white sharks as growing to at least 6 m and 3,000 kg, with a torpedo-shaped body, pointed snout, black eyes and large serrated teeth, grey or bronze above and white below. WA's SharkSmart program notes they have a heat-exchanging circulation that lets them keep their body temperature up to 14 degrees C above the surrounding water, which helps them tolerate a wide range of ocean temperatures.

Young white sharks eat squid and fish, including rays and other sharks. Larger animals add seals and sea lions, dolphins and whale carcasses to the menu (Australian Museum). That diet is why seal colonies shape where adults turn up.

Their life history is slow. CSIRO reports that females in Australian waters do not breed until they are about 5 m long and roughly 16 years old, carry their young for around 18 months, produce up to 10 pups per pregnancy and do not breed every year. Lifespan estimates vary between studies: the Fisheries Research and Development Corporation (FRDC) report card gives a maximum age of 30-44 years, while the Australian Museum cites radiocarbon work that estimated one large male at 73 years.

Cage diving at the Neptune Islands

South Australia's Neptune Islands Group (Ron and Valerie Taylor) Marine Park, 60-70 km south of Port Lincoln, is the only place in Australia where you can cage dive with white sharks. The sharks come for the fur seals: the islands host around half of Australia's long-nosed fur seals and are the state's most important nursery for their pups (SA Marine Parks).

SA Marine Parks lists two operators offering in-water white shark tours, both departing Port Lincoln: Calypso Star Charters and Rodney Fox Shark Expeditions. Rodney Fox runs the only liveaboard at the Neptune Islands, with multi-night expeditions that offer surface cage diving and ocean floor cage dives. The company traces its story to 1963, when Rodney Fox survived a white shark attack while spearfishing off Aldinga Beach.

The industry is tightly managed under the South Australian White Shark Tour Licensing Policy. A 2024 monitoring report by Flinders University researchers, published through SA Marine Parks, notes that the policy caps operator licences, operating days (currently 12 per fortnight) and food-based attractant (currently 100 kg a day). Licensed operators can attract sharks with fish-based attractant and underwater sound. The North Neptune Islands Sanctuary Zone has been fully protected from fishing since 1 October 2014, and landing on the islands requires a permit.

When to go, and a reality check. Acoustic tracking from 2013 to 2024 found more white sharks at North Neptune between October and February and in May, and fewer in March-April and June-September. Sightings are never guaranteed: in 2023-24 operators saw no white sharks on 47% of the days they visited the islands, so ask about recent sightings before you book.

Are great white sharks dangerous to divers?

Yes, they can be, and it is better to say so plainly. The Australian Museum describes the white shark as one of the few shark species that is dangerous to humans. An analysis of the Australian Shark-Incident Database, maintained by Taronga, found white sharks responsible for more recorded bites in Australia than any other species: 361, ahead of tiger sharks (229) and bull sharks (197), in records going back to 1791. Taronga notes that white, tiger and bull sharks account for most serious bites and fatalities.

The same records also put the risk in proportion. Taronga's own figures put that in proportion: over the past decade Australia has averaged 27 shark incidents a year in which someone was injured, and 2.7 fatalities a year, across every species and every kind of water user. CSIRO points out that divers and other water users see white sharks far more often without any aggressive interaction than with one, while stressing that the presence of a large shark should always be taken seriously.

SharkSmart habits for divers

WA's SharkSmart program offers advice that translates directly to diving:

- Dive with a buddy. - Keep away from seals, large schools of fish and wildlife behaving erratically. - If spearfishing, do not carry dead or bleeding fish on you, and get speared fish out of the water quickly. - Avoid water where human or animal waste enters the sea. - Check SharkSmart alerts before you go, and report any sighting to authorities.

Western Australia also offers residents a $200 rebate on approved personal shark deterrents, pitched at surfers and divers. NSW runs a SharkSmart program of its own.

Protection and conservation

The white shark is listed as Vulnerable and Migratory under the EPBC Act, and it has been listed as vulnerable under Commonwealth law since 1997. It is protected in all Australian states; NSW, for example, lists it as Vulnerable under the Fisheries Management Act 1994. Internationally it sits on CITES Appendix II and CMS Appendices I and II, and Australia's national recovery plan, first adopted in 2002, was revised in 2013.

Ongoing threats include bycatch in commercial and recreational fishing, shark control programs, and illegal trade in jaws, teeth and fins (FRDC). The FRDC assessment considers the Australian population stable after historic declines, but still at relatively low levels. The white shark shares its place on the EPBC list with another shark east coast divers know well, the grey nurse shark, whose east coast population is listed as Critically Endangered.

Sources

- CSIRO: White shark research findings - CSIRO: Putting a number on white shark populations (2018) - Australian Museum: White Shark, Carcharodon carcharias - DCCEEW: EPBC Act listed sharks and rays - SA Marine Parks: Shark cage diving - Rodney Fox Shark Expeditions - Huveneers et al. (2024): Residency of white sharks at the Neptune Islands Group Marine Park, 2023-24 - Riley et al. (2022): The Australian Shark-Incident Database, Scientific Data - Taronga: Australian Shark Incident Database - SharkSmart WA: Stay SharkSmart

Header photo: A great white shark (Carcharodon carcharias) in open blue water, photographed off Isla Guadalupe, Mexico, in August 2014. by Elias Levy, CC BY 2.0, via Wikimedia Commons.jpg).