Frederick Reef is just a dot in a very large ocean, the tip of an ancient undersea volcano rising steeply from 2,500m to the surface and on top of which over thousands of years, a coral reef in the shape of a ‘J’ has formed. The coral changes in form depending on where it is located on the reef, on the exposed side where the swell of the ocean rises up into breaking waves the coral grows like the hardy shrubs on a windswept mountain – low and close to the ground. It is here that we expect to find evidence of the Royal Charlotte striking the reef. Travelling from the south, with the ocean swell and strong south-easterly gale behind them, the sound of the roaring breakers in the night was the terrifying sound which alerted the ship’s crew to the presence of a reef – too late.
Millions of years have shaped these reefs. The story of a shipwreck and the intervening 200 years before we travel out into the Coral Sea to search for it is less than the blink of an eyelid in the timeline of this ocean. It is believed that Frederick Reef at times of lower sea-levels was an island that has since been submerged by rising sea-levels. Now, it is only two sand cays (one at the north end and one at the south end) and ‘Ridge Rock’ which remain above sea level. It would have been a bewildering, frightening and very lonely place to find yourself shipwrecked in 1825.
The remote nature of the Coral Sea reefs means that each of these reefs is unique in terms of its fish and coral populations. As an underwater photographer I find this intriguing, when you head to a Coral Sea reef it is a bit like a ‘mystery box’ or Forest Gump’s ‘box of chocolates’ – you never know quite what you are going to get. What you do know is you will find beautiful clear waters, and stunning underwater seascapes. Another exciting aspect is that the Coral Sea has been identified as a global biodiversity hotspot for pelagic predators (sharks, tuna, billfish, etc.) and if you love sharks like I do, that is a wonderful concept in a world where shark populations are in sharp decline. The federal government is deciding the fate of this hotspot right now – so if you believe in shark and ocean conservation, please make sure you have your say.
Although we have the help of two survivors accounts, these accounts contradict each other in the location of the wreck compared to the main landmark of the reef – the sand cay. The other clue we have is the shape of the reef itself. It is all the small clues – wind and sailing direction of the ship, descriptions in the account, the movement of the current – that are used by the archaeologists to start our search in the area of greatest probability for success.
The research and piecing together of clues pays off, on our first dive of the expedition timber is found. A piece of wood may not sound exciting, however when it potentially comes from a shipwreck nearly 200 years old the hand signals being used for communication get significantly more animated! If there is one artefact then possibly there are more nearby and a quick search pattern reveals a large metal bracket (over a metre in length), later identified as a staple knee which is used to hold deck timbers together. You cannot exchange words underwater but you can certainly communicate; the energy and smiles were lighting up the ocean.
This was a great start, but a piece of timber does not make a shipwreck and this piece was a long way from the reef edge, on the sandy bottom of the lagoon. What those two artefacts did give us though was a starting point. Over the next few days teams searched using manta boards, snorkel lines, underwater metal detectors and magnetometers. Our eyes became trained to find the unnatural: straight lines, the green of copper or the black of iron, even the round shape of Thames River gravel which was used as ballast. Often excited moments were followed by the solemn shake of an experts head as they kindly informed us our grand find was a piece of dead coral. The searching was productive though, as each artefact was found and photographed, then mapped and sketched it added to a picture that was beginning to emerge.
We had dives when we were certain this was going to be the moment, this must be where the ship was wrecked, and then we would return with only a few clues: a piece of ceramic half buried, a small amount of anchor chain, a few fragments of glass. The Charlotte must be close, but it was eluding us, all the clues were suggesting we were in the right area, this was the right age of ship, but where was the anchor? Where was the canon? Then one morning I got a call across the radio “Xanthe would you like to do one more dive with us this morning?” one of the dive teams casually asked. Now generally, there are two reasons I might get a call that: 1) they know that I love diving and any time spent underwater or 2) I am the photographer and if you have found something special then you want it photographed and hence I get a call. I tried to keep my hopes in check. Maybe they have just found another amazing dive site?? That would still be quite alright in my books. When I got to the site on the outer edge of the reef, beyond the surf break, their eyes and huge smiles gave them away. “It’s the anchor, a 12ft long and 6ft across anchor the right shape and everything”.
Australian Conservation Foundation