This solution made everybody happy. A lot of students accompanied me on many trips and before long I had thousands of corals to play with. That was all very well, but having a lot of corals wasn’t much use without knowing what they were, something I was clearly unable to work out. I could soon recognise dozens of kinds of coral and give them nicknames, but when I tried to identify them from the taxonomic volumes that meant something to me, I always came up with a litany of vague alternatives.
As I quickly discovered, the essential problem was that corals on reef slopes vary their growth form and skeletal structure according to the environment in which they grow. Thus a familiar coral growing on a wave-hammered reef front might be compact with short stumpy branches. If that coral is common it’s a simple matter to follow colonies of it down the reef slope to deep water, whereupon the same species gradually turns into something quite different, perhaps developing long branches. These different forms had been given different names by the experts because, I realised, without scuba these experts had never seen corals as I was seeing them. To make matters more complicated, big colonies regularly have one growth form at their top, different growth forms on their sides, and different forms again at their base. These growth forms had often been given different species names.
I decided to work these variations out – I had to, so that I could separate a single species from a group of related species – but I gave up trying to stick names on them. I lost faith in the idea that any clear picture of Great Barrier Reef corals would emerge if I relied on historical taxonomy: I would have to start from scratch, observing what could be seen on reefs rather than what was written in monographs. Eventually I decided to stop calling my work taxonomy altogether and instead call it population ecology. That at least seemed an escape route.
Had I made the wrong decision in abandoning insects? I began to seriously think so.
As luck would have it, the Second International Coral Reef Symposium was to take place in June 1973, and it was to be an event like no other. The organisers, the Great Barrier Reef Committee, chartered a 10 000-ton cruise ship, the Marco Polo, to take participants from Brisbane to Lizard Island in the northern Great Barrier Reef and back to Brisbane.5 This amounted to ten days of talking day and night, drinking beer, diving, and generally having a good time.
There were 264 scientists aboard: a perfect opportunity to meet the most important people in the business, especially for me, a novice. The first important person I met was David Stoddart, a freckled, red-headed, somewhat stout character with a deep resonating voice and pure Cambridge accent. By that time he was a seasoned and well-known reef geographer.
‘My dear fellow,’ said David, ‘how very nice it is to meet you. Sorry to have to tell you, but your paper was rejected – Pat Mather’s doing of course. I thought it the best of the bunch. But she doesn’t approve of people like you messing around with taxonomy.’
‘Oh?’ Pat Mather was a curator at the Queensland Museum.
‘In fact yours was the only paper to be rejected,’ he said, ‘but never mind, I’ve put it in anyway. Pat won’t notice, damn silly woman. More to the point,’ he continued, ‘why don’t you join our expedition later this year to the northern Great Barrier Reef? Bring the Kirby – go right to the top end. Would be great fun, eh? Don’t forget to bring lots of booze, there’s a good chap.’ Then off he went.
A few days later, I was sitting at a table on the aft deck having breakfast and nursing a hangover when a middle-aged lady with large glasses walked up to me, smiling.
‘Charlie Veron! What are you doing here?’
I had no idea who she was. I could only sit and stare at her.
‘I’m Isobel Bennett.’ She watched, still smiling, as that slowly sank in.
‘I’m working on corals,’ I said, for want of anything else to say.
‘Really? I thought you’d come back to the sea. You went to Armidale, didn’t you? I lost track of you after that. Well, catch you later.’ She disappeared.
As it turned out we didn’t have that catch-up; in fact I didn’t see her again that trip. Need I say that she left me curious as to how she’d recognised me. I was twenty-eight by then and had no distinguishing characteristics, except perhaps a husky voice and bushy beard. The only other time she’d seen me – when my mother took me to visit her – I was eight. I wondered about Issie, as everyone called her.
The Marco Polo continued on to Lizard Island, stopping at places of interest where it was met by launches to take divers out to pre-selected spots. The weather was mostly bad, the currents were mostly strong, and the divers mostly beginners. There were many rescues, one involving about ten divers strung out over hundreds of metres of open ocean, caught in a current and waving frantically as sharks (or so they no doubt imagined) circled. Sharks or no sharks, it’s amazing that everybody lived through that symposium.
On the last night, after we’d left the southernmost reefs and were heading back to Brisbane, the whole ship’s company met on the aft deck for a farewell buffet dinner and ‘ball’. That company included Cyril Burdon-Jones. I was on the dance floor when he walked up to me.
‘Enjoying yourself, are you? I didn’t think much of your paper, so I’m thinking I should find a more suitable person for your position.’
That sure took me by surprise. My paper had been well received, but that aside, I felt that his threat to sack me yet again, at that particular moment, was simply evil.
If I’m going to get sacked I may as well do it in style.
I grabbed the professor by his tie and shouted loudly that I was going to throw him overboard. It must have looked rather comic – the normally dignified Burdon-Jones being dragged across the dance floor, struggling like a spaniel on a leash. Some revellers around us started clapping; the professor was finding out what young people thought of him. At that point I let him go and he scurried off, not to be seen by anybody for what remained of the trip.
Once back in Townsville I wasted no time seeing Ken Back, the vice-chancellor, to get his approval – on the off-chance that I would still be on the university payroll – to use the James Kirby for the last phase of David Stoddart’s expedition. This wasn’t my first meeting with Ken. A few months earlier he’d summoned me to his office to haul me over the coals for writing to the local newspaper about a nickel refinery’s plan to dump wastewater into the ocean just north of Townsville.6 His beef was that I’d used the name of the university in my letter and shouldn’t have. I saw his point, but left his office talking about Kirsty and how my post-doc was going. I had the feeling that I’d met a friend.
Ken and I talked a long time about Stoddart’s proposal. He said he would discuss it with Davie Duncan, the skipper of the Kirby. The main part of the expedition was to take place in the central Great Barrier Reef; our part involved the Kirby, with me in charge, collecting Stoddart and some others and heading north to the Torres Strait, exploring the outer reefs as we went. It would be the first research expedition to the northern Great Barrier Reef.
A heavily laden James Kirby heading north on its maiden voyage, the Stoddart Expedition of 1973. As of 2016 this amazing vessel was still in service.
Underwater utopia
The Great Barrier Reef is known throughout the world as one of the greatest natural ecosystems on our planet. It is the largest and most spectacular structure built by living organisms on Earth, its size virtually impossible to comprehend. The first astronauts saw The Reef from outer space, the only living thing on Earth they could see. I’ve not had that pleasure, but I have seen it many times from the air. One of those times, thirty years ago, I had a bird’s-eye view from the nose cone of a Neptune bomber, sitting beside the then minister for science. As the plane flew on, hour after hour, one reef region after another came and went in what, for the minister, must have seemed like an endless progression of more and more of the same: he kept falling asleep. Poor man, he was frequently woken by my outbursts of enthusiasm as one favourite dive site after another
came into view, yet when I retraced our flight path on a map after landing, we were both reminded that we’d covered but a fraction of the whole. Even from the air the Great Barrier Reef is too big to take in.
Diving on The Reef is something else again. Only the best movie photographers can capture the ambience of pristine coral gardens. These contain a profusion of life: corals, soft corals, fish, anemones, urchins, starfish, shellfish, and little creatures everywhere, a diversity never seen on land, not even in rainforests. Then there are the underwater cliff faces and ceilings of caverns ablaze with the colours of filter feeders: ascidians, sponges, sea-fans, crinoids and more soft corals, most beyond the knowledge of science.
Reefs in poor condition feel like graveyards, because divers hear only the bubbles from their own breathing. Between breaths such reefs are morbidly silent. Healthy reefs are the opposite; the healthier they are, the noisier they are, because they’re full of little animals all with something to say. This is especially so at night, when even a torch beam can start a cacophony of crackles, chirps and croaks. Some come from fish and are identifiable, but most come from unseen little critters, of which there are thousands of different kinds.
To dive at night is to enter a spectacular world, for the diver’s torch reveals these tiny animals by the thousand: iridescent clouds of plankton of all shapes and sizes, swimming frantically, lured by the light. At night corals open their tentacles to catch these little animals, transforming themselves into anemone-like creatures with long sinuous tentacles, quite unlike their daytime guises. At night, too, large predators of every description move through the distant darkness. Sharks roam unceasingly, sensing the presence of anything moving in the dark.
Photographers sometimes capture these scenes, by day and by night, but they can never convey the emotions of those of us fortunate enough to have looked upon this world first-hand. The greatest reefs of the Great Barrier Reef always instil awe and wonder. The sight of large animals – whale sharks, manta rays, giant groupers, a dozen kinds of big, ocean-going silver fish, sharks and the occasional whale – never fails to thrill. But there’s also fear, especially on the lesser-known outer reefs of the far north. The threat of depth is ever-present, for clear-water reefs that plunge down into deep ocean can be deceptive, a fatal attraction for a tourist wanting to get just a little more out of a trip of a lifetime. Sadly, a spectacular reef face is the last thing some ever see.
Electronic navigation and satellite imagery have virtually put an end to The Reef’s reputation for being one of the world’s most dangerous places for ships. Today, tropical cyclones are more feared than reefs, but there was a time when the Great Barrier Reef had more shipwrecks than the rest of Australia’s coast combined. A glance at any chart shows why, for there are thousands upon thousands of reefs of all shapes and sizes hidden just below the surface and enveloped by strong tidal currents. These form complex mazes from which, in a storm, there is little chance of escape without modern navigation and powerful engines. I have come across dozens of ghostly wrecks on The Reef, usually unexpectedly and always making me wonder what happened to the crew.
Although I’ve worked in almost all the major reef regions of the world, most of the exceptional dives of my life have been somewhere on the Great Barrier Reef.
My studies of corals started taking shape, and the more I saw of the Great Barrier Reef, the more big-picture questions arose. How did reefs grow? Why did they exist at all? Why did corals do all this building? Did they need reefs? Why did corals make colonies with such spectacular architecture? Why were so many different kinds of just about every major marine animal group to be found on them? Had it always been so?
We have answers to most of these questions now, but when I started thinking about them it seemed like trying to put together a dozen great big jigsaw puzzles all at once, with the majority of the pieces missing.
‘The Great Barrier Reef is only ten thousand years old,’ a colleague of mine announced during a seminar thirty years ago. She was both right and wrong, because there’s another player in this game: sea level change. Sea level change makes the Great Barrier Reef both old and young irrespective of geology or biology. It depends on one’s point of view.
John Chappell, a reef geomorphologist at the Australian National University, lateral thinker and good friend, had been making intriguing discoveries about sea level changes for decades, not on the Great Barrier Reef, but in Papua New Guinea, for when it comes to sea level you can work wherever uplifted reefs are best preserved, as the sea is almost the same level everywhere. During the ice ages the sea level went up and down in response to massive polar ice shelves forming, melting and re-forming, taking thousands of cubic kilometres of water out of the ocean and then returning it. In resolving the complexities of sea level changes, John took his inspiration as much from coral ecology – the living veneer seen underwater – as from geology. Certainly, it is the life on a reef, overwhelmingly corals, that builds reefs, but it is mostly the power of waves that cuts them down. Both processes are slow, taking hundreds of thousands of years, far slower than sea level changes, so reefs during the ice ages continually played catch-up with the sea. Some lost the race and drowned because the ocean was too deep when they started growing and their essential life support, light, was cut off.
Glacial cycles have changed the sea level, but only by about 150 metres or so and only during the Ice Age. Far greater changes result from sea floor spreading as continents move. That is decidedly geological and is full of crises. At one point in time the Mediterranean was not a sea, but a gigantic hole some 1500 metres deep on average and much deeper in some places. This hole was filled when the Atlantic broke through the Strait of Gibraltar 5.3 million years ago, forming the mother of all rapids, a single event in geological time that must have caused the sea level to drop enough to kill every coral that grew on a reef flat the world over.
Little did I know in my early years as a scientist that changes in the Earth’s orbit around the sun – Milankovitch cycles, which pace glacial cycles in much the same way as a pendulum paces the speed of a clock – are another ingredient in this already heady array. Milankovitch cycles control glacial cycles, which control sea level changes, which make reef corals ephemeral, super-competitive, and addicted to algae: the story of coral reefs does indeed go all the way from astronomy to cell physiology in a single string of processes varying in time intervals from millennia to days.
I had something else to puzzle over in my early years, closer to home. Were reefs biological or geological structures, and if they were both, where to draw the line? In 1976, two professors at the University of Queensland edited a two-volume book about coral reefs, one volume devoted to biology, the other to geology. These emphasised the division, and the problem became worse when I read an article in which the author claimed that reefs were ‘fragile’. Reefs fragile? That was like calling a dam wall fragile. Argument about this separation of biology and geology went on for at least two decades, generating continual controversy.
We now understand that the living veneer of a reef is indeed fragile, because it is restricted to the interface of land, sea and air, zones where nothing else survives because they are the most violent places on earth when storms arrive. It is this living veneer that gets consolidated, by yet other types of algae and by the chemical action of rain and seawater, into a solid limestone reef, which is anything but fragile. That fragile organisms should build such enduring structures is one of Nature’s great paradoxes. We need to take a close look (as we later shall) at the ecological environment of corals to see how this is done.
I never researched any of these subjects personally, I just thought about them, mostly by sitting in a dingy with my toes in the water or on a beach, gazing out over a reef: a great way to occupy a lot of time.
A reef flat exposed at low tide on the Great Barrier Reef. The corals seen here and in the photograph below are at environmental extremes and have little in common.
A garden of
coral in a protected muddy embayment on the Great Barrier Reef.
Reef builders
Coral reefs the world over are mostly built by coral, something they’ve been doing for hundreds of millions of years. This makes them the greatest builders that have ever existed, only to be pipped at the post very recently by us. Despite their extraordinary achievements, a coral is a simple organism, with the basic design of a sea anemone. Some have soft bodies but these are only very distantly related to hard corals, the Scleractinia, and there are many other differences, the most important being that it is the hard corals that build reefs, using the energy-capturing ability of green plants to do so. Hard corals, unlike anemones and soft corals, have skeletons of limestone, all with intricate designs. Some live alone and so are called solitary corals, but most that are found on reefs form colonies consisting of hundreds to thousands of tiny individual animals called polyps, all working together to produce the architectural masterworks we can see.
It has long been known that reef corals (sometimes called hermatypic or zooxanthellate corals) have minute algal cells (zooxanthellae) inside the cells of their inner body layer, and that these tiny algae produce nutrients by photosynthesis. Len Muscatine, an inspirational American coral physiologist, was making great strides in this field when I was doing my early work on corals, claiming that algae produce most of the nutrients that corals need.
A Life Underwater Page 9
