Clever device stops goannas making a meal of baby turtles
A PLAN to stop goannas raiding loggerhead turtle nests has been hatched by researchers in a trial using new protective devices at Wreck Rock Beach, south of Agnes Water.
Aspiring turtle mothers are having their eggs stolen from the nest, but not for long if a new device can catch goannas in the act.
The device is shaped like a little cattle grid, and sits over the nest. Its holes are big enough for baby turtles to squeeze through but small enough to keep goannas out.
Made from aluminium, the predator exclusion devices do not interfere with the baby turtles' use of the Earth's magnetic field for navigation.
WWF-Australia has teamed up with a local conservation group to support the trial use of 30 devices from December 2013 to the end of February 2014.
Saranne Giudice of the Burnett Mary Regional Group said said the group had already photographed a goanna failing to reach protected eggs.
Volunteers Nev and Bev McLachlan have monitored turtles at Wreck Rock Beach during the nesting season every year, starting on their honeymoon in 1977, and patrol the 22km beach every night.
"We tag turtles that come in to lay eggs and when the baby turtles emerge we check how many hatch and look at ways to improve that success rate," said Nev McLachlan.
Wreck Rock Beach is the second largest breeding site for the endangered loggerhead turtle in the South Pacific Ocean, and used to host thousands of the turtles but now there are less than 500.
The turtles were being killed in fishing nets at sea and by foxes on land, but now that turtle exclusion devices have been fitted to all trawlers and fox baiting programs have been successful on the mainland, the decline in numbers is turning around.
- Named after their large heads, loggerhead turtles have powerful jaws they use to crunch up shellfish.
- Female loggerhead turtles weigh between 76 - 149 kg and are about 1 metre long.
- The turtles lay 127 eggs every 3 to 4 years, from October to March.
- In the mid-1970s about 3500 loggerhead females were breeding in Queensland.
- In the 1999-2000 breeding season there were fewer than 500 nesting females.
- Loggerhead turtles were being killed in fishing nets and on land by foxes, but now that turtle exclusion devices have been fitted to all trawlers and fox baiting programs have been successful on the mainland, the decline in numbers is turning around.