Rosser Reef - Great Barrier Reef

Forget what you think you know about Pacific Northwest diving. Gabriola Reefs isn’t about dramatic walls or deep wrecks, it’s about the sheer, glorious abundance of smaller life, packed into a relatively shallow, accessible area. We love dropping onto the sandy patches between the rocks here, where you’ll often spot slender soles doing their best impression of a discarded leaf, or the surprising flash of a Northern Smoothtongue. The real show, though, is the macro. Bring your best lens, because the nooks and crannies are stuffed with character. Yellowleg Pandalids wave their antennae from every crevice, and the vibrant orange of Sweet Potato Sea Cucumbers adds a shock of colour against the greens and browns. You’ll find star ascidians clinging to the rock faces and, if you look closely enough in the eelgrass beds, the delicate forms of Slender Blade Shrimp. We’ve even seen Dungeness and Red Rock Crabs marching across the open sand – they’re bigger than you expect. It’s a photographer’s dream, particularly for those who appreciate the smaller wonders. We’d suggest a slack tide dive; the currents can pick up, but when it’s calm, you can just drift and observe.

Location: Great Barrier Reef, Australia, Australasia
Coordinates: -15.616667, 145.516660
Type: reef

Marine Protected Area: Annan River

Best Time to Dive in Great Barrier Reef

The warmest water temperatures in Great Barrier Reef occur in February, averaging 29.5°C. The coolest conditions are in August at 25.0°C.

Monthly Water Temperatures

January: 29.4°C
February: 29.5°C
March: 29.2°C
April: 28.4°C
May: 26.9°C
June: 25.8°C
July: 25.1°C
August: 25.0°C
September: 25.4°C
October: 26.6°C
November: 27.7°C
December: 29.0°C

Nearest Dive Centres to Rosser Reef

Marine Life in Great Barrier Reef

Home to 163 recorded species including 88 reef fish, 61 hard corals, 9 seagrass & algae, 2 sharks & rays, 1 starfish, 1 sea snails & nudibranchs.

Notable Species

thalassia (Thalassia hemprichii) - Seagrass & Algae
halodule (Halodule uninervis) - Seagrass & Algae
cymodocea (Cymodocea rotundata) - Seagrass & Algae
Great hammerhead (Sphyrna mokarran) - Sharks & Rays
Bullethead Parrotfish (Chlorurus sordidus) - Reef Fish
seagrass (Halophila ovalis) - Seagrass & Algae
Cauliflower coral (Pocillopora damicornis) - Hard Corals
Lineated Butterflyfish (Chaetodon trifasciatus) - Reef Fish
Dusky Parrotfish (Scarus niger) - Reef Fish
Blackspot Surgeonfish (Acanthurus nigrofuscus) - Reef Fish
Bird wrasse (Gomphosus varius) - Reef Fish
Blue-lined Tang (Zebrasoma scopas) - Reef Fish
Telescopefish (Epibulus insidiator) - Reef Fish
Banded thicklip (Hemigymnus fasciatus) - Reef Fish
Fluorescence grass coral (Galaxea fascicularis) - Hard Corals
Blunt-head Parrotfish (Chlorurus microrhinos) - Reef Fish
Staghorn coral (Acropora hyacinthus) - Hard Corals
Chameleon Parrotfish (Scarus chameleon) - Reef Fish
Citron Butterfly (Chaetodon citrinellus) - Reef Fish
Black-back Butterflyfish (Chaetodon melannotus) - Reef Fish

Recommended Packing List for Rosser Reef

Based on average water temperature of 27.3°C, currents 17 cm/s.

Shorty or Rashguard - warm 27°C water needs minimal exposure protection
Mask - essential for every dive
Fins
BCD - buoyancy compensator
Regulator - your most safety-critical piece of gear
Dive Computer - tracks depth, time, and NDL
Surface Marker Buoy (SMB) - essential for boat pickups
Dive Torch - useful for crevices and colour at depth
Underwater Camera - capture your diving memories