A groundbreaking innovation, the ‘larval seedbox’, is offering hope for the restoration of the Great Barrier Reef’s degraded coral reefs. Developed by CSIRO, Australia’s leading science agency, in collaboration with Southern Cross University, this technology is a game-changer.
The initial trial results are nothing short of remarkable, with coral settlement rates skyrocketing up to 56 times across vast reef areas. Conducted at Lizard Island in 2024, this trial showcases the immense potential of seedboxes in scaling up coral restoration efforts.
Dr. Christopher Doropoulos, a Senior Research Scientist at CSIRO, describes the seedbox as a straightforward yet highly effective and cost-efficient tool. It aids in enhancing coral larval survival, delaying their dispersal, and guiding them towards optimal habitats for settlement.
“The seedboxes act as a delivery system, providing coral larvae with the time and space to disperse and settle on the Great Barrier Reef. Here, they can establish themselves and flourish into juvenile corals,” explains Doropoulos.
The process involves culturing coral larvae post-spawning, an annual mass reproductive event where various coral species release eggs and sperm into the water for external fertilization. This allows researchers to collect tens of millions of coral larvae, which are then used to fill the larval seedboxes.
“The seedboxes are then deployed onto the reef, and the larvae exit when they’re ready, drifting with the currents to cover vast reef areas spanning over two hectares. This approach ensures a high density of larvae over significantly larger areas than ever achieved before, thus boosting the potential for large-scale coral restoration,” Doropoulos adds.
As the annual mass coral spawning event unfolds across the Great Barrier Reef in November, a second trial is currently underway in the Whitsundays. Professor Peter Harrison from Southern Cross University highlights the value of this research in testing the technique’s effectiveness across diverse reef conditions.
“We’re preparing to release up to 20 million larvae at multiple locations, and the team will monitor the long-term effectiveness of the larval seedbox delivery over the next nine to twelve months,” Harrison said.
This collaborative research project between CSIRO and Southern Cross University is supported by the Great Barrier Reef Foundation and involves the Australian Institute of Marine Science and local stakeholders. The paper detailing the success of the first trial at Lizard Island will be published in Ecological Applications, offering further insights into this promising coral restoration technique.