LOVE the LANET
As the Great Barrier Reef marks its 40th birthday as a World Heritage Area, The Weekly celebrates this precious underwater sanctuary and asks what we can all do to protect its future.
The sea is mirror-still and pure tropical turquoise. At the water’s edge thousands of endangered green turtles paddle in the shallows, waiting to nest in Raine Island’s warm, white, softly sloping sand. This tiny, remote coral cay on the far north-eastern edge of the Great Barrier Reef is the most significant green turtle nesting site on Earth, a critical seabird rookery and one of the great success stories in the increasingly fraught battle to save the reef.
Five years ago, hatchling numbers were plummeting, and scientists raised the alarm. A collaborative project was launched between the Great Barrier Reef Marine Park Authority, mining company BHP, the Queensland government, and the Wuthathi and the Meriam Nation people from the Eastern Torres Strait Islands of Ugar, Mer and Erub.
Sand was reprofiled and fencing was installed to prevent falls from rocky habitat. And since then, scientists and rangers estimate roughly 640,000 extra turtles have hatched on the island and made their way into the deep, blue Pacific. It’s a good news story on the reef at a time when good news is in short supply.
This year is the 40th anniversary of the Great Barrier Reef’s declaration as a World Heritage Area, and it has also seen UNESCO (the United Nations Educational, Scientific and Cultural Organisation) threaten to declare the reef “in danger”. The United Nations confers World Heritage status on relatively few precious places on Earth based on their “outstanding universal value to humanity”, and the label comes with a responsibility for the host country to protect the site for future generations.
The questions that have been raised this year are, is the reef in danger and is Australia doing enough? In the past, concern has focused on threats from agricultural run-off, mining, shipping and coal ports within the marine park. But now the threat of climate change has far outstripped all those.
The Great Barrier Reef’s iconic status is unquestioned. It is one of the seven natural wonders of the world
“It’s like a symphony playing underwater. There is nothing like it.”
and the largest living structure on the planet – so immense it can be seen from space. The 348,000km² in the World Heritage Area are made up of 3000 separate coral reefs, 980 islands, countless seagrass and mangrove forests, sandy cays, sponge gardens and other rare habitats which are home to 215 species of bird, 30 species of whale and dolphin and 1625 species of fish – 25 per cent of all the world’s known marine species, and new ones are still discovered every year.
Distinguished Professor Peter Harrison from Southern Cross University, who has been working on reef ecology and coral reproduction for more than 40 years, suggests the
Great Barrier Reef is like the Amazon rainforest of marine ecosystems.
“Reef systems are the most complex, biodiverse systems on the planet,” he tells The Weekly. “Most people think of tropical rainforests as the great centres of biodiversity, but coral reefs are at least their equivalent – there are actually more types of organism on a reef.”
Peter says the Great Barrier
Reef is unequivocally in danger, primarily as a result of humaninduced climate change, and that it’s critical we act now to save it, both for its scientific value and for the breathtaking natural beauty it contains.
Peter describes the first coral spawning that he and his colleagues witnessed back in 1981. “It was an awesome experience,” he says. “I wish everyone on earth could experience mass coral spawning.” He’s seen many such events since, and his sense of wonder is undiminished.
“Most of the corals on the Great Barrier Reef are hermaphrodites,” he explains. “They produce both sperm and eggs and they wrap them together into tiny, colourful bundles … Then, when the colony is ready, dozens, then hundreds, then thousands of polyps release these bundles synchronously. In many cases they just do it on one or two nights of the year. We still don’t understand why so many different species spawn together, but they do, and you’ve got this kaleidoscopic colour of egg and sperm bundles floating off the coral colonies and gently drifting up to the sea’s surface. If it’s a calm night, quite often I turn my torch off and watch the spawning in the moonlight. It’s like a symphony playing underwater. There is nothing like it.”
That first underwater epiphany led to Peter’s groundbreaking reef restoration research, which has become popularly known as Coral IVF. Peter and his team collect just a tiny fraction of the eggs and sperm at spawning, nurture them in “larval pools” until they have successfully cross-fertilised, and then after they develop fully the coral larvae are seeded back onto the reef.
Corals are not particularly successful breeders. Fewer than one in a million larvae settle on a productive patch of reef and grow to adulthood naturally. Peter’s success rate so far has been in the region of one in 15,000.
This research is part of an initiative called the Reef Restoration and Adaptation Program, which brings together some of the greatest minds in Australian and international reef research. Among the highest profile projects are the breeding of heat tolerant corals, cooling and shading interventions to protect the reef from damaging episodes of extreme heat and sunlight, and cryopreservation
(or freezing) of coral cells for reef regeneration. The latter project is a joint initiative between the Smithsonian Institute in the United States, and the Taronga Conservation Society, the University of NSW, the Australian Institute of Marine Science and the Great Barrier Reef Foundation in Australia. It is the most ambitious