Meet the site
Dangerous Reef is a low, flat reef-island in lower Spencer Gulf south-east of Port Lincoln that holds a special place in shark-diving history. The Marine Life Society describes it as a key hunting ground for great white sharks and one of the world centres for shark cage diving, adding that shark visits were intermittent – several on one trip, none on another. In the 1970s it was the site of pioneering white shark filming, including footage associated with Jaws, and of early cage-diving expeditions. The island supports a major breeding colony of pinnipeds. The Society calls it the second largest breeding colony of fur seals in Australia; the colony is also widely recognised as one of the most important breeding sites for the endangered Australian sea lion. The seals and sea lions are what attract the sharks. Today, landing is prohibited without a permit and, as the Society notes, there is no reef diving at the island. White shark cage diving in South Australia is licensed only at the Neptune Islands, so Dangerous Reef is not a recreational dive site. It is included in this directory for its historical significance and to make clear to readers that it is not a site to plan a dive around. Boat-based wildlife viewing from a respectful distance may be possible in calm weather, but operators today focus on the Neptunes and on sea lion swims at Hopkins, Grindal and Blyth islands.
Research this site before booking Stored site notes may be historical. These questions highlight gaps without turning old instructions into a current dive plan.
Dangerous Reef is recorded as Island in Eyre Peninsula. The listed access is boat (day trip). Confirm the actual meeting point, route and permission to visit; a map pin does not establish any of these.
Historical access notes exist for this record, but have not been independently verified for current use. Request current directions from the operator or site manager rather than following an old entry description.
Questions, answered
Is Dangerous Reef suitable for my certification?
The record lists Snorkel/Any. That does not establish suitability for every route or day. Share your training, recent experience and equipment needs with the operator and ask about the specific proposed dive.
Can I book Dangerous Reef through YouDive?
YouDive is an independent research directory. Contact an operator directly to confirm whether it currently runs the trip, the inclusions and the booking terms.
What you might see
Australian sea lions (major breeding colony), fur seals, great white sharks (historically studied here), seabirds
Location
Low, flat reef-island about 30 km south-east of Port Lincoln in Spencer Gulf, hosting a major pinniped breeding colony and historically a key white shark cage-diving and filming site; landing prohibited and no recreational reef diving.
Facilities nearby
None.
Before you make plans
Conditions, access and operator schedules can change. This is a location guide, not a dive plan. Ask a local operator about current conditions and suitability for your training and experience.
Sources & further reading
marinelife.org.aumarineparks.sa.gov.auRecord updated 26 Sept 2026. Source claims are being reviewed.