Scuba Diving Cairns

Thetford Reef

Thetford Reef stretches for almost 2 kms. It consists of a series of scattered coral bommies bejeweled with vivid hard and soft corals and supports a diverse wealth of marine life, making it a wonderful Cairns dive site.

If you peer down to the sandy floor at 25m, there are channels which run between the many bommies. Here you might see some of the giant clams that the area is so well known for. Some examples reach several metres in length!

Stingrays also frequent these channels often half-burying themselves in the sand. You should also keep an eye out around the many overhangs and ledges of the bommies where you can spot and take some great photographs of turtles at rest.

In some places the coral bommies meet overhead, creating swimthroughs that are perfect backdrops for underwater photos. The swimthroughs have gorgonian fans in them that are home to tiny critters, easily spotted by the keen eye. Be sure to take extreme care in the passageways though, and don't brush against the gorgonians as they damage easily.

The bommies are surrounded by marine life with wrasse, angelfish, triggerfish and parrotfish, all being present in large numbers. Keep an eye out for Napoleon wrasse frequenting the reef, one of the highlights of scuba diving in Cairns.

Anemones are plentiful and several species of anemone fish live amongst them. Patches of staghorn between the bommies harbour good numbers of butterfly fish, damsels and angelfish. Multi coloured Christmas tree worms are also found on many of the bommies, which can provide plenty of amusement if you haven't come across them before.

Thetford Reef lends itself to underwater photography, with the shallower depth and sandy bottom providing plenty of light. The only problem is that there's just too much marine life to choose from and you find that your memory card just isn't big enough.

With a healthy population morays you will have no trouble spotting them and there's always a possibility of a chance encounter with an octopus moving across the coral landscape.

Some of the Cairns diving boats that visit Thetford Reef to do fish feeding, so if you find that a trevally, emperor, red bass or even a school of fusiliers or sergeant majors are following you, don't panic, they have simply mistaken you for a waiter.

Thetford Reef Basics: Coral bommies
Depth: 5 - 30m
Visibility: 10 - 20m
Currents: Gentle
Surface conditions: Calm - choppy
Water temperature: 25 - 30°C
Experience level: Beginner - intermediate
Number of dive sites: 1
Diving season: All year round
Distance: 55km east of Cairns
Access: Australia liveaboards

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