2023 restoration efforts yield high success rates

March was an ambitious month for Coralku as we embarked on a large coral planting efforts to outplant 1000 corals. We outplanted 1025 corals from 25 species at the Batu Kuching and House Reef restoration sites. With this large outplanting effort, we took the opportunity to study the impact of coral source on restoration success. The coral fragments were collected from various sources - 408 corals of opportunity, 603 corals nurtured in nurseries, and an additional 16 corals from the Coral Garden. Moreover, to study the impact of substrate conditions on coral resilience and health, 444 were attached to unbrushed substrate, while

583 were secured to brushed substrate. 

Initial results from monitoring conducted in October 2023, revealed an overall survivorship of 61.1%, with 626 corals successfully weathering the transplantation process. Further analysis of the survivorship data showed variations among different coral sources and substrate types. Corals of opportunity displayed a 50.0% survivorship, while nursery corals exhibited a more robust 59.3% survivorship. However, Coral Garden fragments experienced a lower survivorship rate at 25%. These figures indicate that corals nurtured in controlled environments, such as nurseries, exhibited a higher survivorship rate compared to those procured opportunistically.

Corals planted on unbrushed substrate showed a higher survivorship at 68.5%, compared to the 55.2% survivorship observed for corals planted on a brushed substrate. The higher survivorship observed with unbrushed substrate may indicate that unbrushed substrate provides a more natural or suitable surface for coral attachment to facilitate a stronger attachment between the coral fragments and the substrate. This, in turn, can contribute to better stability and increased chances of survival for the transplanted corals.

These findings emphasize the need to carefully consider coral source and substrate conditions in coral restoration projects. Understanding how different coral source and substrate types influence coral survivorship is crucial for optimizing restoration success. We aim to monitor these corals again in 2024 and gain insights to improve our reef restoration strategies.