Meeting Abstract

P3.64  Friday, Jan. 6  A molecular assay for the cause of bleaching in the temperate Atlantic coral species Occulina arbuscula FUESS, L.E.*; SHEDLOCK, A.M.; WHAM, F.C.; DUSTAN, P.; College of Charleston; College of Charleston; Pennsylvania State University; College of Charleston lefuess@g.cofc.edu

The causation of bleaching of the temperate scleractinain coral, Oculina arbuscula is being investigated over the course of seasonal warming off Charleston, South Carolina from June to October. Reports of coral bleaching on the wreck of the Freddy Day were confirmed during the summers of 2009 and 2011. Previous data suggests that the seasonal bleaching has decreased the total coral coverage of the reef, however the cause of bleaching is still unknown. Additionally past research has indicated that due to the temperature range of the site, adaptive bleaching of symbiotic zooxanthellae is not occurring. Data collected for site temperature shows a positive correlation between increasing temperatures and bleaching events. Additionally, other species of Oculina have been documented to bleach in the presence of high temperatures due to infection by Vibrio shiloi. We are employing PCR-based species-specific DNA sequence analysis in order to distinguish between thermal stress and bacterial infection and to determine the actual cause of bleaching on the reef. DNA samples are extracted from coral samples taken off of the research site during periods of known bleaching. PCR primers specific to Vibrio shiloi 16rDNA sequences are used to amplify any DNA present from the target pathogen in mixed environmental samples, then products are sequenced to confirm taxonomic identification of pathogens. Molecular genetic results will be discussed in relation to pinpointing the exact cause and infectious nature of bleaching and can provide a more predictive framework for understanding the present and future status of this reef and those like it in temperate Atlantic coast zones.