Engineering of coral reef larval supply through transplantation of nursery-farmed gravid colonies

The continuous worldwide degradation of coral reefs raises an urgent need for novel active restoration techniques as traditional conservation practices have failed to impede the incessant reefs' decline. While applying the “gardening coral reefs” methodology in Eilat (Red Sea, Israel), we examined reproductive outputs of naturally-grown and outplanted, nursery-farmed Stylophora pistillata colonies from three coral-transplantation trials (November 2005, May 2007, and September 2008), along three reproductive seasons. Surprisingly, transplanted colonies showed better reproductive capacities than the natal Stylophora colonies during > 4 post-transplantation years. A higher percentage of nursery-farmed colonies released planula larvae as compared to naturally-grown colonies. Gravid transplants also shed more planulae per colony, yielding significantly augmented numbers of total planulae over naturally developed S. pistillata colonies. Our results indicate that nursery-grown corals may be used to enhance reef resilience by contributing to the larval pool, forming an engineered larval dispersal instrument for reef rehabilitation.

Research Highlights
► We followed planulae release from natal and transplanted, nursery-farmed corals.
► The study was performed on S. pistillata colonies, up to 4 years after transplantation.
► Transplants released more larvae and showed higher numbers of reproducing colonies.
► Nursery-farmed corals can be used as a larval engineering tool in reef restoration.
► Transplantation of nursery-farmed gravid corals can help reseed degraded reefs.