A 60-YEAR-OLD turtle known as the grand old lady of Mon Repos has thrilled scientists by travelling nearly 650 kilometres up the Queensland coast during an exhausting four-week journey.
The flat-back - the world's longest studied marine turtle - was tracked from the famous turtle rookery near Bundaberg to feeding grounds in Repulse Bay, north-west of Mackay.
The travel secrets of the turtle - known as X23103 - were unlocked by a transmitter looking like a tiny blue backpack which provided researchers with a satellite record of her post-breeding migration.
"It really is an incredible journey by the grand old lady,'' said Environment Minister Dr Steven Miles.
"We know she left Mon Repos on December 10, and travelled 645 kilometres before arriving in Repulse Bay on January 7.
"During her 28-day journey she hugged the coast from Mon Repos to Gladstone and north to Byfield, then striking out into deeper water, through the Percy Islands and Cumberland island groups, before stopping at Repulse Bay just south of the Whitsundays," Dr Miles said.
"She's been foraging there in a fairly small area for the last six weeks, and it will be interesting to see where she goes next.
"We are following her travels over 4-5 months while the transmitter remains attached,' he said.
The Queensland Government's turtle research program has been monitoring the "grand old lady' since 1974 - placing a numbered metal tag on her at the beginning of her breeding life, when she would have been about 21.
Department of Environment and Heritage Protection Chief Scientist Dr Col Limpus said that over the 41 years she'd been studied, the turtle had been recorded in 15 seasons, coming ashore to lay on a total of 72 occasions, always on the 1.6km of Mon Repos Beach.
"After a five-year gap, it was exciting for EHP scientists, the Queensland Parks and Wildlife Service rangers, our volunteers and visitors, to see her again this season at Mon Repos,' Dr Limpus said.
"She laid four clutches, starting with a clutch of 30 eggs on 17 October, and all four of those clutches have hatched.
"She used to breed about every two years and lay about four clutches of eggs, but later in her life she has generally laid fewer clutches with longer intervals between breeding seasons.
"This may be the consequences of old age, and we need observations of more turtles of similar age to confirm this," he said.
This has been a good breeding season at Mon Repos, the most important marine turtle rookery on the eastern Australian mainland.
Since late October 2015, a total of 387 loggerhead turtles, seven flatbacks and one green turtle have come ashore multiple times to nest. Eggs began hatching out in early January, with the tiny hatchlings making their way down the beach in their perilous start to life.
More than 24,000 visitors have come to witness the wildlife spectacle on this season's nightly Turtle Encounter tours.
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