In the canoe is Dr Scarla Weeks, a senior researcher here at the Coral Reef Ecosystems lab, escorting a pretty ill looking ‘teenage’ turtle that she stumbled across in the middle of Moreton Bay. Scarla mentioned that she found the turtle floating on the surface, and noticing that it was covered in algal slime and unable to dive to depths, (precariously) balanced the turtle on her kayak and called the veterinary team at Australia Zoo upon return to land. An isolated event? Apparently the turtle Scarla reported was the 5th to be collected from the bay that Sunday morning alone…
The cause of ‘floating’ turtle syndrome is often due to the ingestion of plastic bags and other marine waste – fishing line, balloons, bottles. Unusual? Not really – a recent study on leatherback turtles went as far as to suggest that a third of adult turtles had remnants of plastic in their digestive tracts. Stuck at the surface and unable to feed, ‘floating’ turtles undergo a prolonged death of starvation and exposure to the sun.
In recent months , the numbers of turtles and dolphins washing up dead on the shores of Moreton Bay has come under scrutiny in the media. Last week, several adult female dugongs were found washed up along the shore lines, and at least three dolphin carcasses were found floating in the middle of the bay since August. The Wildlife Preservation Society of Queensland reported that over 10 dead turtles were reported in the bay in the last 2 weeks, along with at least 5 sick turtles reported by Scarla above.
So what’s killing the turtles and marine life of Moreton Bay? Whilst John Thorogood, an aquatic biologist at FRC Environmental suggests that something is happening to the water quality in the Bay, renowned turtle expert and chief scientist Col Limpus suggests that the number of deaths in recent weeks isn’t unusual, and likely reflects animals in poor condition not surviving through the winter months. The jury appears hung on the exact cause, but Scarla suggests that a recent dramatic winter cooling of ocean temperatures in the Southern Great Barrier Reef and offshore of Moreton Bay of upto 2 degrees from normal conditions might be responsible for the upsurge in marine deaths, but plastic & marine debris appear to be major contributing factors.