Mass starvation of dugongs and turtles on Great Barrier Reef
By Jonathan Pearlman, Sydney
Along hundreds of miles of beaches and on the shore of small islands, the rotting carcasses of green turtles and dugongs have are being washed ashore in alarming numbers – victims, scientists believe, of the after effects of the cyclone and floods that have afflicted this part ofAustralia in the past year.
Now naturalists fear that up to 1,500 dugongs – a species of sea cows – and 6,000 turtles along the Reef are likely to die in the coming months because their main food source, sea grass, which grows on the ocean floor, was largely wiped out by the floods and cyclone.
In some places the plants were ripped from the seabed by currents created by the storms and in others they were inundated under silt and soil washed out from the land by the torrential rains.
Beachgoers have reported stumbling across groups of turtles in shallow waters near Townsville – only to discover they were dead or dying.
“This is a long-term environmental disaster,” said Dr Ellen Ariel, a turtle expert at James Cook University.
“It is not like an oil spill where you can clean the water and move on. It is such a large stretch of coastline… We have had mass strandings of turtles. The turtles are sick and starving and can’t go on any longer. They don’t have anywhere to go.”
The Great Barrier Reef Marine Park Authority says it expects more dugongs to die than in any previous event.
Marine experts have expressed growing concerns about the future of the Reef’s dugongs, which are regarded as a vulnerable species. The herbivorous creatures, related to the Florida manatee and believed to be the source of the mermaid myth, helped the Great Barrier Reef gain its listing as a World Heritage area in 1981.
But their number around the southern parts of the Reef, which attracts the largest number of tourist, has declined by an estimated 95 per cent over the past 50 years. Some 5,500 live in the main section of the Reef, and here growing numbers of carcasses have been washing up on to coastal golf courses and island beaches.
Clive Last, who works as a groundsman on a privately-owned island near the town of Gladstone, was making his way back to the shoreline on his boat last month when he spotted a “black bulge” on the rocks of a small island, Witt Island. He made his way to the pontoon and discovered the marooned body of a seven-foot dugong, with much of its skin peeled away.
“I could see straight away there was something there that shouldn’t be there,” he told the Sunday Telegraph.
“I thought, not another one. It was a big grey and white dead mass, but it was intact. There was no sign of trauma or cuts or bruising. Something is going wrong. I’ve lived here for 50 years but I have never seen deaths in such numbers.”
Mark Read, a protected species expert at the Great Barrier Reef Marine Park Authority, said turtles and dugongs were the “lawnmowers of the sea” and their losses could have a damaging impact on the overall marine ecology.
“We are looking at the highest ever record for stranded dugongs and the same for turtles,” he told The Sunday Telegraph.
“Turtles and dugongs play a key role in maintaining healthy seagrass beds. We have concerns about the likely effect from a marked decline of turtles and dugongs. We don’t know what the consequences are.”
One of the world’s experts on dugongs, Prof Helene Marsh, from James Cook University, said she was concerned about the dugong’s future in the southern section of the Reef. “It is unprecedented that such a huge area of coast was affected. In this case, because the floods and cyclone were so huge and the damage so widespread – and it followed a wet year last year – we are wondering whether these animals have anywhere else to go.”