Growth and Survivorship of Meandrina meandrites and Montastrea cavernosa Transplants to an Artificial Reef Environment, and the Effectiveness of Plugging Core Holes in Transplant Donor Colonies

The growth and survivorship of two species of scleractinian coral transplants, Meandrina meandrites and Montastrea cavernosa, were investigated. Identically sized replicate transplants were obtained from the second reef, off Dania Beach, using a hydraulic drill fitted with a 4” core barrel. The transplants were fixed to Reef Ball™ substrates using an adhesive marine epoxy. Drill holes in the donor corals (core holes) were filled with concrete plugs to prevent the detrimental effects of bioeroders. Control corals, of comparable size to both the donor colonies and the transplant corals, were selected for comparison. The transplant corals, donor corals, and controls on the natural reef were monitored for growth and survivorship. The core holes were monitored for tissue regrowth over the surface of the concrete plug, in order to assess the effectiveness of the plugging process. Growth during the transplantation project was defined as an increase in surface area or radius, and was monitored on a quarterly basis using photographic techniques. SigmaScan© Pro4 image analysis software (Jandel Scientific Corporation) was used for the analysis of the photographic data. The following main hypothesis was tested: species-specific differences will occur in the responses of coral colonies to drilling and transplantation. Additional sub-hypotheses were tested, including: 1) a change in surface area and/ or radius in the experimental corals and the control corals will take place, 2) the survivorship of the experimental corals and their control corals will be similar, 3) a change in surface area and/ or radius of the tissue surrounding the core holes will take place. Meandrina meandrites transplants exhibited a substantial amount of mortality and displayed significantly less growth (both in surface area and radius change) than M. cavernosa transplants, and the M. meandrites controls. Montastrea cavernosa transplants experienced significantly more growth than their same species controls. All donor corals that experienced drill damage (separate from the drill holes) were able to regenerate the injured tissue in a period of less than three months. No significant difference was found for the change in percent tissue coverage for either donor species when compared with each other and with their same species controls. Tissue did not completely regenerate over the surface of the concrete core hole plugs in either species. However, there was no significant difference between the initial area/ radius of the core holes and the final area/ radius for either M. meandrites or M. cavernosa. Additionally, there was no significant difference in the total area change of the core holes when the two species were compared. The results of this study indicated that M. meandrites did not demonstrate statistically significant survivorship or growth as a transplant coral. The M. cavernosa transplants were successful, and displayed a significant increase in surface area. The areas surrounding the core holes did not significantly increase in surface area in either species of donor corals