We acknowledge the Traditional Owners of the land ono which we conduct this work and pay our respects to their ancestors past, present and emerging.
For the last three years we have been implementing and trialling a range of innovative coral reef restoration techniques in two bays on the Whitsunday’s region of the Great Barrier Reef. The project has brought together a number of organisations passionate about the Reef and looking to implement activities to support the health of the reef.
Monitoring in May 2020 showed that 430 recently propagated corals were showing a mean survival of 72% across all sites and locations. Survival was higher in Manta Ray Bay (78%) over Blue Pearl Bay (65%). Of our two methods survival was slightly higher on the coral discs (74%) than on the ropes (70%). Overall many of the corals in the nurseries were looking healthy, well and as expected five months since propagation.
Over the last two years we have outplanted over 1300 corals at experimental sites in our two locations. Some of our target outplanted corals are looking fantastic and starting to have a visible influence on the reefscape, transforming the barren rock and rubble into small havens of life. Coral colonies are starting to make their own self attachments to the reefscape, a key step in their transition from nursery to foundational benthic species.
Over the last 18 months it is true that many of the outplanted corals have not survived. This has been due to a number of disturbances including algal overgrowth, localised bleaching and heavy predation by bumphead parrotfish. Despite these challenges there are signs the previously barren landscape is slowly starting to transform into a more diverse and complex environment that will support greater reef health and diversity.
It is well known that coral propagation using active reef restoration techniques like these are slow, laborious processes. In the Whitsundays it feels like these processes are going even slower. Heavy sedimentation and seasonal algae blooms are likely to be important players in limiting growth and heavy predation is playing a role in survival.
Is Local Stewardship Important?
We work with local tourism operators who are regular visitors to our research locations. Regular training and participation by tourism representatives enables these important stakeholders to assist us in monitoring and maintaining our coral nurseries and outplant locations. Most of the times there is little to do while the corals are growing and developing. Tourism operators help us by being our Eyes on the Reef providing real time updates on survival and the general health of the project. Sometimes nurseries need maintenance due to compromised infrastructure than can temporarily be repaired until more permanent solutions are implemented.
Another important partnership for this project has been with the Coral Nurture Program and their innovative outplant technique using the CoralClip TM. The CoralClip is a unique tool, a nail with a spring that enables simple and efficient outplanting of coral colonies.
We are enjoying the journey in the Whitsundays as we learn what works, and what we need to change as we look for solutions going forward.
Background to the project
Active reef restoration is designed to assist the recovery of coral reefs on small cases where these projects are implemented.
We have been trialling a number of different methods and techniques rebuild the foundational benthic organisms common coral reefs, coral. Using a technique called coral gardening, we use asexually propagated coral collected from nearby reefs to populate underwater nurseries. These nurseries house multiple species of corals where they are reared from 9-12 months.
Infographic from the Reef Restoration and Adaptation Program (RRAP) restoration toolkit. (link)
They have multiple objectives not only aiming to improve the ecological values of the reef, but the socio-economic objectives are also a high priority for this project.
Why these locations?
The two locations we are working on, Manta Ray Bay, Hook Island and Blue Pearl Bay Hayman Island were heavily damaged during ex-Tropical cyclone Debbie in 2017. We conducted a comprehensive site assessment of over 20 locations in the Whitsundays looking for sites that had been heavily degraded and would be suitable candidates for some assistance. We were also looking for locations that still have some remnant coral cover to provide source material for the propagation of coral nurseries.
Additionally, we conducted extensive consultation with the local community, Traditional Owners and the tourism industry who advised on locations that were important to them. The tourism industry in particular were keen for some assistance to the two locations, Blue Pearl and Manta Ray Bay, which they had previously visited extensively and were not substantially different following the cyclone.
Where do you find coral?
Coral is sourced from nearby reefs that still have a remnant coral cover of higher than 30%. Before we take corals, we conduct surveys to ensure there is enough coral cover that taking coral is not going to negatively impact the source sites. Additionally, we preferentially take what we call ‘corals-of-opportunity’. These are corals that have broken and are lying loose around the reef with a low percentage chance of survival due to potential sedimentation and smothering in the sand. Using corals of opportunity ensures we have minimal impact on our source locations.
What methods do we use?
We use two types of coral nurseries, a table with small 80mm circular coral discs onto which we ‘plant’ a small coral colony. The send type is using ropes which hold coral colonies within their strands. Both nursery types are anchored to the sea floor and suspended in mid-water. This method is designed to enable dynamic movement in the water potentially reducing sediment that could compromise the survival of nursery reared corals.
Why are we using these methods?
These methods are simple and easy to use. This means that the skills require minimal scientific knowledge or experience to implement and maintain. The idea is that the technology and methodology is easily transferred to community members who have opportunities to participate and contribute to actions that support reef health. These methods could be implemented by tourism organisations and potentially represent alternative income streams in the future. Easily transferable skills and knowledge will enable capacity building that can empower the local community and industries to undertake similar activities. This type of stewardship can significantly support the health of reefs on local scales.
Additional benefits include the awareness raising activities that come with involving a variety of stakeholders. When people get involved they learn about the challenges the reef is facing and are encouraged to implement changes in their everyday lives to reduce carbon emissions and mitigate the effects of climate change.
- From Guides to Gardeners, how these tour operators are replanting the Whitsunday’s coral reefs (Link)
- Watch the movie – from Guides to Gardeners (Link)
This project has also been supported by the Australian and Queensland governments, Daydream Island Resort, G Adventures, Planeterra Foundation, Citizen, Explore Whitsundays, Tourism Whitsundays and the Whitsunday Regional Council. Additional support from Aqua Dive, Ocean Rafting, Red Cat Adventures, Prosail Whitsundays True Blue Sailing and the Reef Islands Initiative, a program of the Great Barrier Reef Foundation, supported by funding from Lendlease, the Australian Government’s Reef Trust, the Queensland Government and the Fitzgerald Family Foundation.