In the gardening approach for reef restoration, coral stocks are farmed in underwater nurseries (phase I) prior to their transplantation onto degraded reefs (phase II). The phase I aspects were already evaluated in the literature, but very little is known about the phase II outcomes. Assessing phase II feasibility, we transplanted 554 nursery-farmed colonies of two branching species (Stylophora pistillata, Pocillopora damicornis) onto five denuded knolls in Eilat (Red Sea). The performance of the transplants was compared for 17 months with 76 natal colonies and 217 colonies maintained at the coral-nursery. At the natural reef, rates of full/partial mortalities, detachment and fish herbivory were considerably higher than the nursery values. While corallivory on Pocillopora transplants was comparable to that observed in natal colonies, herbivory on Stylophora transplants increased 2.2 fold compared to natal controls. Their survivorship was similar to the survivorship observed in natal colonies in the 9 months post transplantation, but was 30% higher after 17 months. In contrast, no enhanced mortality was documented in Pocillopora transplants throughout the entire period. The detachment levels of the Stylophora and Pocillopora transplants were 3 and 10 times higher, respectively, than those observed in natal colonies, and the growth rates of the transplants were identical to the rates observed in the nursery control groups. Transplants showed a 2.5-3.3 fold increase in colonial ecological-volumes, resulting in enhanced acquired space/habitats for coral-dwelling species like Trapezia, Alpheus, Spirobranchus and Lithophaga. The successful integration of farmed transplants in Eilat's degraded reef and their provision of new ecological niches for reef-associated fauna, coupled with economic assessments, indicate that transplantation of farmed corals is an easy, cost-effective mean to counteract degradation of coral reefs. Results also imply that the selection of coral species for reef restoration should take into consideration their autogenic/allogenic engineering properties, particularly if the aims are to restore the whole reef community, rather than simply focus on coral coverage.
Bibliographical noteFunding Information:
This project was supported by the INCO-DEV project (REEFRES, No. 510657), by CORALZOO, an EC Collective Research project (No. 012547), by the AID-CDR program (No. C23-004), by the partnership between NAF-IOLR and JNF-USA, by a grant from the Israeli Ministry of Infrustructure (B.R.) and by the Rufford Small Grants Foundation (Y.B.H.F). We would like to thank Ido Izhaki for statistical advice, Nadav Shashar for his support, Dudi Gada and the Ardag staff for their help and hospitality, the Meduza dive center staff for technical support, Dror Fridman for helping in the field and Guy Paz for assisting with the graphics. We are grateful to all the volunteers that helped with coral preparation and transplantation.
© 2015 Elsevier B.V.
- Ecosystem engineers
- Gardening approach
ASJC Scopus subject areas
- Environmental Engineering
- Nature and Landscape Conservation
- Management, Monitoring, Policy and Law