Australia: Mystery turtle deaths stump scientists

The Australian 25 Jun 12;

THE mysterious death of 22 green turtles, a protected species, is puzzling experts in North Queensland.

The experts have not ruled out poisoning and even drowning as a cause.

The Department of Environment and Heritage Protection is investigating the deaths of the turtles found at Wunjunga Beach, about 100 kilometres south of Townsville.

The department's director of threatened species, Wolf Sievers, said the vulnerable animals have been washing up on the beach for over a week.

"It is very unusual for this many turtles to have stranded on one beach and we will be making every effort to establish what may have happened," Mr Sievers said.

Senior turtle expert Dr Ian Bell said that initial investigations found no injuries, no obvious signs of malnutrition or illness.

"It's a bit like turtle CSI, it's all about ruling out possible alternatives," Dr Bell said.

"We're ruling out starvation. It doesn't look like it's any infectious type of disease, and it leaves us with two possibilities.

"One is potential poisoning, and we're also looking at the possibility of a drowning.

"At this stage we really don't know."

The department hopes they will be able to establish the causes of death after performing further necropsies.

The entire Great Barrier Reef is an important feeding area for green turtles, which are classified as a vulnerable species nationally under legislation.

All of the green turtles, except one, have been large adult female green turtles. Adults have a shell length of about 1m and average about 130 kg, although some nesting females can weigh more than 180 kg.

A loss of just one breeding size individual can have an impact on the species.