A guest post for Scubaverse by Chloe Brown.
Chloe is a graduate from the University of Southampton where she studied for a BSc Oceanography. She started her diving career whilst studying, which led to her current job working for Velaa Private Island in the Maldives. Chloe works together with the resident marine biologist and coral biologist restoring the house reef while conducting new innovative research to improve restoration techniques.
The reality of climate change beneath the waves is more detrimental than the majority are aware. Among all the reefs found across the globe, 50% have been destroyed in recent years in response to anthropogenic stressors. Unfortunately, these beautiful habitats are tucked away and the effects easily go unnoticed, deteriorating further. This is not the case for the diving community who are unfortunately witnessing this rapid decline in corals and marine life. Therefore, multiple restoration efforts worldwide have jumped in to attempt to restore one of the world’s greatest wonders, before it is too late.
Restoration Techniques
Coral restoration initiatives aim to restore the overall health, abundance, and biodiversity improving the reef’s tolerance to external stressors. The process behind this is to utilize the existing corals to clone them and repopulate the reef. The fact these corals are still surviving on the reefs, despite the natural disturbances, indicates strong resilient characteristics that are very valuable to restoration projects. These corals act as “donor colonies” as small fragments are broken off to be grown in nurseries and later transplanted back onto the reef.
Here at Velaa Private Island, we use the floating mid-water nursery set up. These consist of 1,500 corals and we currently have two of these nurseries in place. Our nurseries mainly hold Pocillopora spp. as it is extremely tolerable with a high prevalence rate. We attach the small fragments taken from the donor colonies with monofilament and crimps to the nurseries, where they grow for a year. This nursery is situated at a depth of 8m (anchored at 30m) and located away from the reef. Growing away from the reef reduces predation, moderates competition, and allows depth alterations during warmer months to mitigate bleaching effects. Other key nursery designs are being trialed by other restoration efforts worldwide. These include coral trees, net nurseries, and ex-situ nurseries in laboratories, where the conditions can be monitored and controlled 24 hours a day.
During transplantation, we use marine cement to attach the corals to rocks and other hard surfaces found along the reef. Over time these corals will propagate outwards via asexual reproduction growing over the adhesives securing themselves on to the reef.We have successfully transplanted over 4,500 corals with a 70% survival rate. This has had a great effect on increasing the abundance and diversity of marine life present on the reef.
We have additionally conducted further research into effective ways to restore species diversity, specifically looking at massive species. It was found that massive coral species survive better when the fragments are transplanted directly onto the reef, skipping the nursery phase entirely. The ideal fragment size should be 1-2cm and attached to the substrate 1cm away from its clones, to allow fusion with growth. It was Dr. Vaughn who discovered that massive coral species grow quicker when they are cut into smaller fragments. He also discovered tissue fusion between clones however, his finding was taken from ex-situ experiments. It’s fantastic to see similar results in-situ with all the natural disturbances prevailing. The overall aim of restoration is to rehabilitate the reefs encouraging natural growth and self-sufficiency. We have certainly seen this as there was higher recruitment (coral larvae settlement) number in the transplant sites compared to the untouched degraded sites. Self-generation has been evident.
This is an insight into a few techniques used by restoration projects. Without reef restoration, it is predicted that a complete loss of coral reefs will be seen in the next 30 years, taking away, the home to 25% of all marine life. This signifies the importance of restoration and future conservation measures. To ensure the sustainability of restoration efforts education and awareness need to be conducted. Awareness needs to be ubiquitous as it is not just those living along the coasts who have an impact on the oceans, it’s everyone. People need to be taught about the reality of the ocean to induce a permanent change; otherwise coral reefs will lose the fight against mankind taking the marine life with it.
If you are interested in the work we are doing or just want to see some awesome underwater shots of marine life check out our Instagram page @velaacoralproject. We will be delighted to have you.
