Saving Australia’s only endemic sea turtle.
Each year at Ayr in Queensland, flatback turtles drag themselves up the beach to nest, all under the watchful eye of conservationists.
AS THE FULL MOON peeks through the clouds and the high tide quietly laps the shoreline, we mount a fleet of sandy quad bikes and carefully ride up and down a deserted beach near Ayr in northern Queensland. With a series of bikes in a row, the coastline looks more like a highway than a flatback turtle nesting area. Under the guidance of the local Aboriginal rangers, two marine biologists and a handful of volunteers from Queens Beach Action Group, we look for flatbacks or their tracks. They’re here to lay their eggs, and it’s a vital opportunity to gather data and learn more about this elusive species.
While nesting, flatbacks aren’t hard to find. They leave trenches in their wake as they drag themselves up the beach to the dune. If we find two sets of tracks – up and back again – it means we’ve missed the mother. If we only find one set, she’s either still heading up to the dune to nest, or already laying her eggs.
Finally, we get the call; one of the search parties has found a flatback. When we arrive, we’re told to keep our distance until she starts to lay – too close, and she might spook and return to the water. She digs, moves, digs and moves again, until she finally finds the perfect spot. If nothing else, her indecisiveness is testament to her strong maternal instincts.
“Once she has finished digging and started laying, we can approach her. They are so focused on laying they go into an almost trance-like state and our presence doesn’t seem to bother them,” whispers Ian Bell of the Queensland government’s Threatened Species Unit.
Eventually the digging stops and the 80kg reptile begins laying. This female is seemingly unperturbed by us, and Ian signals for us to get closer. She’s a beauty: olive and yellow with prehistoric-looking flippers and a weather-beaten carapace that, up close, looks like an old treasure map. Unblinking, she is focused on her task and after 30 minutes all 47 of her eggs are laid, and she buries them under almost 1m of sand.
Little is known about the movements and diet of the flatback. This is surprising considering that it is Australia’s only endemic marine turtle (see AG 123). Before letting her return to the water, we take her back to camp so the crew can take samples. At base, the team hastily fits her with a ‘backpack’ satellite tag – worth $5000 – to record the turtle’s location, water temperature and depth. A titanium tag is attached to her flipper and a pit tag is injected under her skin –
like a microchip for pets – to identify her in the future.
Finally, they measure her carapace length and take blood and tissue samples. It’s vital to gather as much information as possible, because it’s invaluable to marine biologists such as Christine Hof of WWF Australia. “We know little about where they forage, what they feed on and the route they take from a nesting beach,” she says.
For the past two years, WWF, the Queensland Department of Environment and Heritage Protection and James Cook University (JCU) have been tracking their migration using satellite transmitters. “Isotope analysis helps determine both their foraging grounds and diet,” Christine adds.“So far, we’ve learnt that adult flatbacks nesting on a beach near Home Hill migrate 490km south to Cape Townshend or 720km away north to Cape Melville, with one turtle foraging way up north near Milman Islet, 1100km away.”
Ian says that they don’t know exactly what flatback turtles eat, “but they are soft-bodied things like sea squirts, soft corals, sea urchins and sponges.That’s about the extent of what we know so far, and this project will help us find out more.”
With so many threats to the marine ecosystem, this study is crucial to the flatback’s survival. With data comes the understanding of how to better protect them and their environment. Along with WWF and JCU, the local Aboriginal rangers have been vital to the management and conservation of the turtle’s habitat. Representing the traditional owners of the Bindal, Ngaro and Juru nations on the Great Barrier Reef coast is a group called the Gudjuda Indigenous Land and Sea Rangers.
Headed by Eddie Smallwood, aka ‘Uncle Eddie’, the team is based in Ayr, with their region covering the Whitsunday Islands up to Townsville. A nimble group of five, they support the local community and environment with training programs, biodiversity surveys, local disaster relief and turtle monitoring, tagging, tracking and protection.
“Our rangers are also helping to preserve and protect our culture, because it’s about our culture being trained back into our people,” he says. “We all need to work together to manage and protect the turtles because if we don’t look after them, who will?”
Once hatched, thousands of baby turtles (opposite) make their way to the sea. Mortality is highest in shallow waters, so they must swim frenetically towards the open ocean.
Satellite tags attached by WWF Australia in 2014–15 reveal the migration routes of four flatback turtles – Badgigal, Gungu, Katya and Wunjunga – as they moved from Shoalwater Bay in the south, to Cape Grenville, near the top of Cape York Peninsula, in the north.
Headed by Eddie Smallwood (right, at centre), local Gudjuda Indigenous Land and Sea Rangers and volunteers catch an 80kg flatback. Flatback eggs (below) are counted and weighed.