Meet the site
Haystack Island is a slab of rock with towering cliffs about 6 km south-west of Stenhouse Bay, part of the Althorpe Islands Conservation Park and, since 2012, surrounded by a habitat protection zone of the Southern Spencer Gulf Marine Park. It is only about 500 m long and 120 m wide but rises 43 m out of the sea, and it hosts breeding seabirds that have made it a permit-only area since 2007. Underwater, the Marine Life Society describes shallow ledges around the island at about 15 m, with crevices and ledges visited by seals, large western blue groper, southern blue devils and plenty of other fish. The ledges are dressed in kelp on top and sponges, ascidians and gorgonians on the vertical faces, and the seals – New Zealand fur seals and Australian sea lions from the Althorpe group – often come to inspect divers. Haystack's bigger attraction is the long reef that runs parallel to the island about 500 m offshore (see Haystack Reef), and most boat trips combine the two: a deeper wall dive on the reef and a shallower seal-and-groper dive along the island. The island is very exposed and currents can be strong, so it is a calm-day site for divers with boat experience and good buoyancy. It is closer and more sheltered than Althorpe Island, making it the usual next step for Innes divers who want wilder diving without the long crossing.
Research this site before booking Stored site notes may be historical. These questions highlight gaps without turning old instructions into a current dive plan.
Haystack Island is recorded as Island in Yorke Peninsula. The listed access is boat. Confirm the actual meeting point, route and permission to visit; a map pin does not establish any of these.
Topics flagged by the stored research
These are questions prompted by the existing notes, not a verified or complete hazard assessment.
- Current and timing
- Ask how the operator assesses the current window for the actual route. Historical tide notes are not a departure instruction.
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 Haystack Island suitable for my certification?
The record lists Advanced Open Water. 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 Haystack Island 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
New Zealand fur seals, Australian sea lions, western blue groper, southern blue devils, sweep, old wives, kelp, sponges, gorgonians
Location
Small, towering-cliffed island (about 500 m long) roughly 6 km south-west of Stenhouse Bay, part of the Althorpe Islands Conservation Park; shallow ledges around the island are frequented by seals, and a separate long reef wall lies about 500 m offshore.
Facilities nearby
None; Marion Bay ramp and services.
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.auen.wikipedia.orgsdfsa.netthediveshack.com.auRecord updated 26 Sept 2026. Source claims are being reviewed.