Caribbean acroporid corals, such as Acropora cervicornis, are essential for maintaining productive reef ecosystems, yet are facing widespread decline due to disease and anthropogenic threats. For this reason, many restoration initiatives in the Caribbean target A. cervicornis as it is fast growing and provides invaluable resources as an ecosystem engineer. Despite these efforts, many environmental threats can lead to dysbiotic microbiome shifts that compromise the success of outplants and native colonies, thereby leading to disease. In some cases, antibiotics are used to mitigate coral disease, yet few studies have investigated how these antibiotics affect apparently healthy coral, or how antibiotic-induced microbiome alterations will impact the coral’s ability to respond to future perturbations. To address this unknown, we conducted an aquaria-based experiment to investigate how two A. cervicornis genotypes with vastly different microbiome structures and varying predisposition to disease respond to antibiotic challenges. Throughout a five-day antibiotic exposure, we collected coral tissue samples for 16S rRNA sequencing and microscopy, as well as water samples for bacterial counts to comprehensively identify genotypic, antibiotic-specific, and dose-dependent microbiome responses. The results from this work provide fundamental information regarding how healthy corals respond to antibiotics, and constitute the basis for subsequent experimentation to reveal microbial mechanisms of coral resilience, recovery, or susceptibility to sequential environmental stressors.

Primary Presenter: Sunni Patton, Oregon State University (pattonsu@oregonstate.edu)

Authors:

Sunni Patton, Oregon State University  (pattonsu@oregonstate.edu)

Denise Silva, Oregon State University  (dapiedad@oregonstate.edu)

Eddie Fuques, Oregon State University  (fuquesve@oregonstate.edu)

Rebecca Vega Thurber, Oregon State University  (rebecca.vega-thurber@oregonstate.edu)