Meet the site
Mantis Reef is a far-northern Great Barrier Reef reef named in Professional Dive Services' account of its MV Kalinda expedition from Cairns to Horn Island, where it appears in a list of Greater Detached Reef sites as 'Mantis / Wishbone Reef'. PDS gives no further description, and none of the other operator pages read for this record documents the site in detail. The expedition it featured on was a 13-night, 12-day trip in November with up to 40 dives, departing Cairns and finishing at Horn Island, with a maximum of 12 divers. PDS described conditions across the far-northern reefs as very challenging, with strong currents, and recommended the trip only for experienced divers certified to at least Advanced Open Water (30 m). Depths across the expedition ranged from 6 to 40 m or more. By analogy with neighbouring far-northern outer reefs, Mantis Reef is likely to offer walls and slopes with gorgonian fans and soft corals, strong currents and pelagic life, but this should be treated as unverified. The site is included for completeness as a named expedition site. Divers interested in the far north should look to the scheduled Mike Ball and Spirit of Freedom expeditions (October–December), which visit Great Detached, Tijou, Cat and Raine Island reefs, and ask whether Mantis Reef is on the itinerary. Given its remoteness, any dive here is an expedition dive: hours from medical help and days from port.
Research this site before booking Stored site notes may be historical. These questions highlight gaps without turning old instructions into a current dive plan.
Mantis Reef is recorded as Reef in Far Northern Reef & Torres Strait. The listed access is boat (multi-day/liveaboard). 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.
- Water movement
- Ask how swell and local exposure affect the proposed entry, exit and route.
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 Mantis Reef 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 Mantis 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
Not documented (expect far-northern outer-reef fauna: reef sharks, pelagics, fans, soft corals)
Location
A remote far-northern outer reef listed by Professional Dive Services among its Great Detached-region expedition sites (as 'Mantis / Wishbone Reef').
Facilities nearby
None – expedition liveaboard only (Spoilsport/Spirit of Freedom provide air, nitrox, meals, cabins).
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
professionaldiveservices.com.auRecord updated 26 Sept 2026. Source claims are being reviewed.