Leopard Sharks in Australia: Where to See Them

Settle onto the sand at Julian Rocks on a warm summer morning and the shapes start to arrive: long, pale bodies dusted with dark spots, each trailing a tail almost as long as the rest of the shark. They glide past in ones and twos, then in loose groups, and on a good day a single dive can bring dozens of them. All of this happens about 2.5 km off Byron Bay, a five-minute boat ride offshore.

These are leopard sharks, and the summer gathering at Nguthungulli Julian Rocks is described as the largest known aggregation of the species anywhere. The sharks are gentle, endlessly photogenic and, across much of their range, in serious trouble. That makes every diver's photo here useful: it can feed into one of the world's longest-running studies of the species.

Leopard shark or zebra shark?

They are the same animal. Australian divers and researchers usually say leopard shark, while overseas it is often called the zebra shark. Both names describe the same fish at different ages. Pups hatch with bold dark and pale stripes, and as they grow the stripes break up into the spotted pattern of the adult.

The scientific name has changed too. For decades the species was known as *Stegostoma fasciatum*, but a 2019 review in the journal *Copeia* concluded that an older name, *Stegostoma tigrinum*, takes priority, and Australian references such as Fishes of Australia now use it. It is a carpet shark in the order Orectolobiformes, the same order as the whale shark.

One more source of confusion: "leopard shark" is also the common name of *Triakis semifasciata*, an unrelated shark in the family Triakidae found in the eastern Pacific from Oregon to the Gulf of California. Search results about Californian leopard sharks refer to that species, not ours.

Identification: stripes to spots

Adults are yellowish to tan or brown with dark, leopard-like spots, prominent ridges running along the body and a very long tail that makes up about half the shark's total length. Juveniles under about 70 cm look completely different: dark brown to blackish with pale bars and blotches.

That banded juvenile pattern appears to be a disguise. Fishes of Australia notes that newly hatched pups strongly resemble banded sea snakes in colour, body shape and swimming movements, and University of the Sunshine Coast (UniSC) researcher Dr Christine Dudgeon worked out that the young sharks are mimicking sea snakes. The stripes fade into spots within a year or two, and the adult spot pattern appears to stay fixed for life, which is what makes photo identification possible.

Adults commonly exceed two metres. The Australian Museum gives a length of at least 2.4 m, possibly up to 3.5 m.

Biology and behaviour

Leopard sharks feed mostly at night, mainly on sea snails and bivalve shellfish, with smaller amounts of crabs, shrimps and small fishes. They squirm into narrow crevices and suck prey out using powerful muscles in the mouth cavity. During the day they are usually sluggish and often rest on the sand.

They lay eggs. Females produce large, dark egg cases about 17 cm long, anchored to the bottom by tufts of hair-like fibres, and pups measure roughly 20 to 26 cm at hatching. Juveniles are rarely seen in the wild, and Dr David Robinson, co-owner of Sundive Byron Bay, suspects females lay their eggs in deeper water beyond recreational diving limits. The species can also reproduce without a male: in 2016 Dr Dudgeon studied a shark in a Townsville aquarium that hatched three pups after such a "virgin birth".

Lifespan is still uncertain. One Byron Bay shark carrying an old tag mark turned out to be a male that Dudgeon had tagged, already mature, at North Stradbroke Island 16 years earlier, which led Robinson to suggest the commonly used estimate of about 25 years may be too low.

The Julian Rocks aggregation

Nguthungulli Julian Rocks lies within Cape Byron Marine Park and has been recognised as an Important Shark and Ray Area, partly because of its leopard sharks. Sundive describes it as hosting the largest known aggregation of the species in the world. The sharks arrive as the water warms: Sundive puts the season at roughly December to April, with the sharks departing in May, and notes they like water above 23°C, so they come and go through the season. On a good dive, Robinson says, you can have upwards of 50 leopard sharks swimming around you.

The gathering is unusual in two ways. It is strongly female: Sundive reports that 80% of resightings are of females, and Robinson describes most identified sharks as adult females, with smaller numbers of mature males and sub-adults. And the sharks are busy. At Julian Rocks most are swimming around during the day, whereas elsewhere, even at North Stradbroke Island, leopard sharks normally rest on the bottom. Males are often seen following females, which Robinson interprets as pre-mating behaviour.

Sundive says most leopard sharks are found over the large sandy arena in the middle of the Needles (9 to 15 m), and the shallower Nursery (6 to 12 m) is also good for swimming with them in summer. For more on the site itself, see our Julian Rocks and Julian Rocks Marine Sanctuary guides. When the water cools, the leopards give way to grey nurse sharks, which take over the rock through winter.

The Cape Byron Leopard Shark Project

Sundive's Cape Byron Leopard Shark Project, a citizen science program that Sundive says has been running since 2003, has photo-identified more than 600 individual leopard sharks. Its partners include the University of the Sunshine Coast, NSW Department of Primary Industries, the Marine Megafauna Foundation, Spot the Leopard Shark and Sharkbook AI, and the work has revealed site fidelity, seasonal aggregation and sex-biased resightings that guide management.

You can contribute. Researchers need a clear photo of the shark's left side, behind the gills and along the body, and sightings can be uploaded to Sharkbook through Sundive's research page.

Where else to see leopard sharks in Australia

Leopard sharks range from Port Gregory in Western Australia around the tropical north to Montague Island in southern New South Wales, as well as several Coral Sea islands. The most reliable encounters are in southern Queensland and northern New South Wales, where mature adults gather in coastal waters each summer.

Manta Bommie off North Stradbroke Island is another summer site. Underwater photographer Nigel Marsh, who has dived it since the early 1990s, describes leopard sharks resting in the gutters and on the sand there through the season, from about November to April. His accounts also name Cook Island off Tweed Heads and Wolf Rock off Rainbow Beach as summer leopard shark sites, with occasional sightings on Ningaloo Reef and the Great Barrier Reef.

Are leopard sharks dangerous?

No. Leopard sharks are considered harmless to humans, and the Australian Museum describes them as unaggressive when approached underwater. Their teeth are small and suited to grasping and crushing hard-shelled prey. The International Shark Attack File lists one documented unprovoked attack on a person, which caused no injury.

That said, Fishes of Australia notes they may bite if provoked, and any shark over two metres long deserves respect. Never grab, ride or corner one.

Diving with leopard sharks responsibly

- Time it right. Plan for December to April and check water temperatures, since the sharks favour water above about 23°C and come and go through the season. - Let them come to you. Hover calmly and let sharks pass rather than chasing them. - Hands off. Do not touch, grab or block a shark's path, and keep fins clear of resting animals. - Respect the reserve. Julian Rocks sits in a marine protected area inside Cape Byron Marine Park, so follow your operator's briefing. - Shoot the left side. A sharp photo of the left flank behind the gills is the most useful image for researchers.

Conservation

The IUCN Red List classes the leopard shark as Endangered globally. Fishes of Australia notes it is heavily fished in coastal fisheries throughout its range except in Australia. "They are not threatened in Australia because we don't fish them," Dr Dudgeon said in a UniSC news story, explaining that overseas they have been over-harvested for fins and meat, and their tough skin has become prized for lining the walls of expensive yachts.

That makes the Australian aggregations important for the species, and Australian aquariums are now helping restock it elsewhere. Female leopard sharks at Sea World Gold Coast and SEA LIFE Sydney Aquarium have been artificially inseminated as part of the Indonesian-led StAR Project, with fertile eggs destined for the Raja Ampat Islands off West Papua to help restock protected waters there.

Sources

- Leopard Shark Research Byron Bay, Sundive Byron Bay - Diving Julian Rocks by Month, Sundive Byron Bay - The Leopard's Lair, Nigel Marsh Photography - Zebra Shark, Stegostoma tigrinum, Fishes of Australia - Zebra Shark, Stegostoma tigrinum, Australian Museum - The Cape Byron Leopard Shark Project with Dr David Robinson, Marine Megafauna Foundation - UniSC helps pioneer wild new shark breeding technique, University of the Sunshine Coast - Zebra Shark, Florida Museum of Natural History

Header photo: A leopard shark (Stegostoma tigrinum) cruising over the reef at Julian Rocks, Byron Bay, NSW, January 2025 by marsyd (iNaturalist observation 257538611), no rights reserved, CC0 1.0 (public domain dedication), via Wikimedia Commons.