Meet the site
Cat Reef lies alongside Tijou Reef on the far-northern shelf edge, and Mike Ball's Northern Exposure expeditions dive the two together: wall dives adorned with colourful fans and soft corals, with barracuda, rays, sharks and turtles and pelagic activity. Scuba Diver Life lists Tijou, Cat, Great Detached and Small Detached reefs as key sites of the Raine Island expedition. The reef's outer face drops steeply into deep water, with gorgonian fans, whip corals and soft corals on the walls and hard corals on the upper slopes. Currents bring pelagic fish – barracuda, trevally, mackerel – and sharks patrol the walls. Turtles are common, especially during the nesting season when thousands head for Raine Island to the north. Named sites on the Tijou/Cat system include Pussy Galore and Catchers Mitt (listed separately); it is not always clear from operator notes which of the two reefs each lies on. The site is visited only on expedition liveaboards, a few times a year, and requires Advanced certification or equivalent. Visibility is typically excellent. Cat Reef suits experienced divers on a far-northern expedition who enjoy wall diving and pelagic encounters. Getting here is itself an expedition: the far-northern reefs lie hundreds of kilometres north of Cairns, are visited by only a handful of liveaboards in the October–December window, and are many hours from medical help, so divers should be current, self-sufficient, carry an SMB and audible signal, and dive conservatively. On Mike Ball's Northern Exposure itineraries the Tijou and Cat reefs are dived over a day of the seven-night voyage between Cairns and Horn Island, typically with up to four dives including a night dive, and the exact sites chosen depend on the weather on the day.
Research this site before booking Stored site notes may be historical. These questions highlight gaps without turning old instructions into a current dive plan.
Cat Reef is recorded as Wall 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.
- Planned depth
- Confirm the intended route and training requirements; the recorded maximum is not a target.
- 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 Cat Reef suitable for my certification?
The record lists Deep/Advanced + experience. 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 Cat 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
Barracuda, trevally, mackerel, grey reef sharks, rays, turtles, gorgonian fans, whip corals, soft corals
Location
A remote outer reef adjoining Tijou Reef in the far-northern GBR, dived for its walls, fans and soft corals.
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
mikeball.commikeball.comscubadiverlife.comRecord updated 27 Sept 2026. Source claims are being reviewed.