Date of Award
Master of Science in Biological and Environmental Sciences (MSBES)
The extent to which coral reefs have declined globally has triggered major scientific investment in coral restoration research. However, much of the predictions for reef futures do not include the capacity for coral acclimatization, or phenotypic plasticity, and how this plasticity varies across seasons. In light of this, we outlplanted clonal replicates of distinct genotypes of the reef building coral Acropora pulchra from an existing coral nursery common garden site to three sites on the North Shore of Mo’orea, French Polynesia. After transplantation (October 2019), the outplanted colonies were sampled at all three sites in January and November of 2020, for the following physiological metrics; maximum photosynthetic rate (Am), photosynthetic efficiency (AQY), dark respiration (Rd), chlorophyll concentration, symbiont density, total protein, and ash free dry weight. Nursery genotypes and wild corals from two of the outplant sites were sampled at the outset of the experiment (October 2019) to provide a physiological baseline, which identified differences in coral physiology between the common garden and the wild corals from the two sites. Our results show that outplanted corals displayed significantly different phenotypes both through time and between sites. Our data show that plasticity score (calculated as the differences in multivariate space between October 2019 and each of the other timepoints for each genotype) was highest across all sites 3 months after transplantation (January 2020) and decreased across all sites by 13 months (November 2020) This identifies a capacity for site driven phenotypic plasticity that became more similar to the baseline common garden phenotype by 13 months, due to location acclimation, or seasonal environmental similarities. This study demonstrates that plasticity varies by site and through seasons, highlighting the need for physiological time series research to interpret performance in following human interventions.
Conetta, Dennis A., "PHENOTYPIC PLASTICITY IN ACROPORA PULCHRA UNDER VARIED ENVIRONMENTAL CONDITIONS" (2021). Open Access Master's Theses. Paper 2100.