SCUBA mackerel islands

Diving around the waters of the Mackerel Islands is an optical feast for any scuba enthusiast. Endless seascapes abound, the hypnotic lure of sea life drifts and rolls like your own private showing of a marine movie. Thevenard Island is the main base, with all the essential facilities required for excellent dive expeditions.

Among the dive sites are Rankin Road, Black Flag, Brewis Reef, Trap Reef, Sultans Reef and Sheltered Coral Gardens – idyllic for underwater photography. Typical creatures to swim amongst include whales, dolphins, gropers, reef sharks, tawny nurse sharks, stingrays, wobbegongs, turtles, olive green sea snakes, thick trevally schools, snapper, pearl perch, fusiliers, batfish and silver drummer.

Dive charters operate from Thevenard Island via our charter vessel, which is also available for scuba sprees and snorkelling adventures.

Whether you’re visiting the Islands on a day trip, an extended stay, or have your own private boat, the Mackerel Islands dive experience is nature at its most beautiful, audacious and challenging.


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Dive Sites

Rankin Road

For those of you who like swimming among BIG schools of fish, Rankin Road is the location for you. Five kilometres from Thevenard Island and 18 metres down, it’s not unusual to get 40 rankin cod following you around while you explore the length of a sub-sea wall. Sea snakes, reef sharks, coral trout and many pelagic species school at this site making it one of the fishiest places to be in the Mackerel Islands. Photographic heaven.

Sultan’s Reef

Closer to Thevenard Island, Sultan’s Reef features a coral lined wall 14m deep rising to 6 metres (tabletop), making for an easy safety stop at the end of the dive. hone uw photography on nudi species / doubling as safety stop. The wall is visited by ‘pelagic’ fish (the pelagic zone is the zone in between the ocean floor and the surface) and observed by permanent reef species. It attracts larger species with mackerel and barracuda schooling the edge. The top of the site contains colonies of anemones and clown fish, colourful soft corals and small ‘benthic’ treasures – treasures found on the sea floor. This site has a lot of potential – being a lengthy wall is yet to be fully explored.

Black Flag

With some of the most brilliantly incandescent corals in caves and ledges sitting 17 metres down, the Black Flag site just has to be seen. Featuring large gorgonians and black coral trees in only ten meters of water, it has resident olive sea snakes, Queensland groper the size of a small car, and sleeping leopard and nurse sharks (which you’ll most likely see on any dive amongst the islands). Black Flag and nearby Paroo Shoals are both favourites for an incredible diversity of nudibranchs, so if you like to look small, these are the sites to see.

Trap Reef

Consisting of many clusters, the Trap Reef sites lie between three and 13 metres deep. Crevices, overhangs and small caves are scattered throughout. Dense clouds of pomfrets and Spanish flag are abundant, while larger coral trout and Chinamen fish lurk in wait. Turtles, reef sharks and mangrove jack have also been frequent visitors. Soft and hard corals in cobalt blue, pink, yellow and vermillion impart kaleidoscopic hues among this beautiful seascape.

Shallow Protected Coral Gardens

Large coral bombies, cabbage leaf and green tree coral outcrops are common to sites located close to the islands. Many of these sites are calm, clear, protected from wind and make for excellent secondary dive locations. Shallow depths (mostly less than 6 metres) give long bottom times, giving you the opportunity to observe more subtle marine interactions. Schooling behaviours, the ‘hide and show’ of irrepressible damsels and chromis make for very calm and relaxing dives.


Here is an article written back in 2010 by Nigel Marsh, and whilst some of the information is no longer applicable (MIDive is not currently in operation, and it’s much easier to get to us now!) it provides a good recount of a dive expert’s experience in our waters. Additional images are available to view on the Nigel Marsh Photography site.