By Bridie Smith.
The lone green sea turtle found stranded and off-course at Ninety Mile Beach on New Year's Eve is on track to be released into the wild within months.
Estimated to be at least 90 years old, the 60-kilogram female turtle dubbed Eve has spent almost three weeks recovering under the watchful eye of marine vets at the Melbourne Aquarium.
Vet Rob Jones said while she was not yet back to normal, she was about 90 per cent recovered.
Dr Jones said she arrived weak and was kept in shallow fresh water for the first week to rehydrate. The fresh water also kills external parasites, barnacles and algae.
Eve was given antibiotic injections to ward off bacterial infections, as the cooler water she was found in slows the metabolism and weakens the immune system in cold-blooded creatures such as sea turtles.
Though she did not eat for the first fortnight, Dr Jones said Eve was now enjoying moderate amounts of prawn and squid. He estimated she probably had not eaten for two months.
''Reptiles have a pretty slow metabolic rate, so they get sick slowly and they get better slowly or they die slowly,'' he said. ''It's often a month or two before we can say, 'Yep, we're out of the woods'.''
While she has been moved to a larger 3000-litre tank and was back in seawater, vets are still waiting for her to pass a stool and for her appetite to increase. The stool sample will also allow vet staff to run tests to establish if there is an internal infection. So far it had been too tricky to take a blood sample, Dr Jones said.
At more than a metre in length, Eve is one of the largest sea turtles brought to the aquarium as part of the rescue and rehabilitation program.
Dr Jones guessed that she may have washed up on Ninety Mile Beach after being swept south by one of the currents on Australia's east coast.
He said at New South Wales' mid-to-south coast the change in water temperature could be dramatic, dropping by as much as 10 degrees in 100 kilometres.
Since 2004 the aquarium has released five rehabilitated green sea turtles. The location of Eve's release is still to be determined but Dr Jones said he expected she would be well enough within 12 months to return to the wild.
A threatened species, green sea turtles are more commonly found further north in warmer, tropical waters. They are among the largest of the sea turtles and can live for up to 150 years.