Queensland is reviving the endangered green turtle population on an island off its shores by rebuilding the beaches where turtles nest. The Raine Island Recovery Project, a multimillion-dollar public-private partnership between the Queensland government and global resources company BHP, sent a team of scientists to Raine Island off the coast of Queensland. By using a combination of conventional and high-tech methods, they have saved more than 600 turtles and increased hatching rates by almost 20% in areas.
Results & Impact
Green turtles are a crucial part of Raine Island marine ecosystems. A healthy successful hatching rate for laid green turtle eggs is around 70%. In recent years on Raine Island, this rate has dipped to as low as 10-15%. The team’s efforts on sections of the beach have seen hatching rates increase to 62.5%, higher than the 46.2% rate in the areas left untouched. The team has also saved almost 700 turtles from death by putting up fences on the island's low cliffs and rescuing trapped turtles.
BHP, Queensland Parks and Wildlife Service, Great Barrier Reef Marine Park Authority, Traditional Indigenous Owners, Great Barrier Reef Foundation
The conservationists visit the island several times a year. Stationed on a boat to the side of the island, they monitor the turtles, their nests and the island's birds whilst working to improve hatching and survival rates. Their biggest intervention to date has been a beach remodelling project. Since 2014, the team has moved 1.8 hectares of beach to raise one of the island’s nesting areas, protecting it from the tidal inundation which floods the turtles' nests and damages the eggs. The conservationists are now experimenting with satellite tracking, remote listening stations, and drones to better understand the causes of the decline of both the bird and turtle populations on the island.
Raine Island, Queensland, Australia
General public, indigenous people
Cost & Value
Running since 2014
Tracking the turtles is difficult, and, with satellite tracking in the early stages of development, patchy. Understanding exactly how the turtles behave between the periods when they come onto the island to nest is difficult, as is working out just why eggs are failing to hatch. Remodelling the beaches has been expensive due to the high cost of shipping the excavation vehicles over from Cairns, some 640km from Raine Island.
The public-private partnership is one of the largest the Queensland government has entered into, in terms of expense. It’s being treated as a model, and, if successful, is likely to be followed by similar programs in the future.
“The idea is to make a turtle factory. A turtle producing factory.”
This is how Tina Alderson describes the Raine Island Recovery Project. As project manager, Alderson and her team are working to revive the endangered green turtle population off the coast of Australia as part of a multimillion-dollar public-private partnership. Using a combination of conventional and high-tech approaches, the team has already been able to raise hatching rates by 20% in the areas it has targeted.
The green turtle population is in worldwide decline, due to decades of poaching, disease, and climate change. The WWF lists green turtles as a priority species, and a vital component in marine ecosystems, such as Queensland’s Great Barrier Reef.
“It’s that mindset change to intervene and do something – not to sit on our hands”
Raine Island, off the coast of Queensland to the north of Australia, is the world’s largest green turtle nesting site. Hatching rates on the island are currently dangerously low. A healthy successful hatching rate for laid eggs would be 70%. In recent years on the island, it’s dipped to as low as 10-15%.
“The project is a pioneering public-private partnership and the first large-scale adaptive management project on the Reef,” said Alderson. “It’s that mindset change to intervene and do something – not to sit on our hands.”
The project’s largest operation to date has been beach remodelling. In 2014 and most recently in August and September 2017, the team has used trucks and excavation vehicles shipped over from the mainland to move thousands of metres of sand, which they employed to completely remodel 1.8 hectares of beach.
Green turtle nests are vulnerable to water damage, and the tides cause water to seep through the sand at the back of the beach where turtles nest. If inundated, the nests and their eggs can be completely destroyed. By moving large quantities of sand at the back of the beach, the project team have been able to raise the nests above the tide and protect them from the water.
“We did that three years ago in a particular sector and then we’ve monitored it for the past three nesting seasons, to see if it got high nesting success to begin with, and then also a higher hatching success. It has done, and was considerably higher in that first season,” said Alderson.
Eggs laid in the February-April incubation period had a 62.5% rate of hatching success, significantly higher than the 46.2% seen in the areas of the beach that hadn’t been remodelled.
The team also had a significant impact on survival rates of the adult turtles simply by putting up fences. By installing 1450m of fence on the one-metre-high “cliffs” across the island, they have managed to save 500 breeding turtles. They also undertake rescue operations to retrieve turtles trapped between rocks: last season they saved 182 from entrapment and death by heat exhaustion.
The project team is now taking the first steps to use high-tech equipment to collect data on the wildlife on Raine Island. For the past two seasons, the team has tagged individual turtles with satellite tracking to try to understand the nuances of their behaviour. Green turtles are elusive and much of their behaviour remains a mystery. A recent report shows that misunderstandings about their laying behaviour may have led to an overestimation of their population by a factor of two, suggesting the sea turtle population may be in even worse condition than previously thought.
“With satellite tracking, you get migration patterns. We get that information and it’s very interesting, but that’s not primarily why we tag turtles at Raine. We kind of know where our turtles go. It’s more about the inter-nesting – what they do between nesting periods,” said Alderson.
The scientists’ aim is to understand how the species on Raine Island are behaving day-to-day, in order to work out what is causing their numbers to decline. To this end, they are now experimenting with camera drones and remote listening stations to pick out nesting birds and turtles and accurately survey the island’s geography. With the equipment, the conservationists can accomplish in an hour what it would take a surveyor two days to do.
“It’s a bit of a guinea pig in some ways. If this works well, we hope it can lead to more of these kind of partnerships in the future”
BHP, a global resources company, alongside the Queensland government has provided funding of $6.2 million (USD) to the project. The funding has been indispensable due to the remoteness of Raine Island, which lies some 640km away from Cairns on the coast of Queensland. Shipping the necessary equipment to remodel the beaches and monitor the animals is particularly expensive.
“The private-public partnership plays a big role in this project,” said Alderson. “It’s certainly the biggest one that the Queensland government’s entered into. It’s a big mind shift for everyone in government, a bit of a guinea pig in some ways. If this works well, we hope it can lead to more of these kinds of partnerships in the future.”
(Picture credit: Gary Cranitch Qld Museum)