A loggerhead turtle dubbed the Comeback Queen is helping researchers unlock some of the mysteries of her species
By Brian Williams
This old girl is changing what the world knows about turtles.
Dubbed the Comeback Queen, she is the star of the world's longest-running turtle study program, having laid eggs at the Mon Repos turtle rookery near Bundaberg since the 1970s.
The endangered loggerhead turtle is thought to be about 65 and has laid more than 13,000 eggs, with as few as one in 1000 of her offspring reaching adulthood.
Environment Department chief scientist (aquatic threatened species) Col Limpus has recorded her ashore 107 times for nesting, her last appearance a week ago.
All but three of those nestings were at Mon Repos.
Dr Limpus said an ultrasound showed she had more eggs, suggesting she would be back at the end of the month.
She is then expected to swim to her regular feeding grounds to feast on crabs and shellfish.
The supermum's fertility has raised questions over where she lives when she is not breeding and why her clutch numbers are rising from about 125 eggs up to 165 as she gets older.
It is hoped a satellite tag will reveal this information.
"We know she's been nesting for at least 33 years," Dr Limpus said.
"It's intriguing to me that she usually lays five clutches, with an average of 128 eggs in each, sometimes every year."
The Comeback Queen and two or three others are teaching the world about their species, such as how long they can live, how often they lay eggs and their level of egg production.
"Now we're getting to study her hatchlings to find out if they change as she gets older.
"We know that in humans there is a higher probability of deformities with older parents so we're looking at this sort of thing in turtles.
"Time will tell and this old lady will be the one to teach us."
Dr Limpus has tracked more than 20 loggerhead turtles and is starting to build up sufficient information to provide definitive answers to issues such as how turtles find their way home after nearly always going to the same beach to lay their eggs.
More than 350 turtles nested at Mon Repos this season, slightly up on last year but down on 2009 and 2010.
"It's what we expected," Dr Limpus said.
"Plumes from extreme flooding smothered habitat with sediment so we are seeing a reduction in breeding as a result of that."