On our 2015 spring cruise from Cairns to Cape York, we took in a slight detour to several nearby Coral Sea atolls, beginning at Bougainville Reef.
We waited for a good- weather window before heading 215km north- east of Cairns to a speck on our chart. Bougainville Reef is a 4km-long, oval atoll formed thousands of years ago by coral growth around the top of an ancient volcano.
A sandy lagoon is all that remains of the volcano’s peak. It’s magical colours and stillness beckoned us to come in – but while the charts clearly showed a navigable entrance, we were not seduced by the lagoon’s beauty. Our dingy survey showed the maps were incorrect and unless we had a jet boat or drew under a metre, it was an accident waiting to happen, even at high spring tide on a calm day.
The atoll bears the name of its first visitor, Frenchman Louis-Antoine de Bougainville. During his exploration voyage of the Pacific in 1766, de Bougainville was confronted with a line of waves breaking over the reef. This near miss, and with his crew weakened by scurvy, prompted him to turn north to New Guinea. Otherwise, he may have discovered Australia four years before James Cook.
For more information from Wikipedia about de Bougainville click here.
Bougainville Reef was a fair-weather stopover, with 15 to 20-knot breezes. The reef’s outer edges have steep walls that fall a kilometre or more to the seabed. While it’s said to be an impossible place to anchor, we found a convenient small sloping shelf at the partially protected north- west corner in a depth of 25 to 35m. We stayed there for three nights, each day venturing out in our dingy to dive and explore.
The diving along the sheer walls was spectacular and we also enjoyed exploring the maze of gutters and caves behind it. Two wrecks lie atop the reef, which we reached in our dingy at high tide. The 4810-ton Atlas is the most interesting and best-preserved wreck, with its remnants reaching well out of the water.
As we were diving without surface support, we stayed alert to the unpredictable, strong currents that occur in such places. Our diving was very conservative, though, with ‘what if’ strategies in place. On our first wall dive, the reef became exposed two hours before low tide, causing the current to pick up speed quickly from the opposite direction! We found diving at high tide the safest bet.
With 25-knot winds coming our way, it was time for our next leg: a 100nm, moonlit cruise north to the big atoll of Osprey Reef.