Inter-Research > DAO > v137 > n3 > p217-237  
DAO
Diseases of Aquatic Organisms

via Mailchimp

DAO 137:217-237 (2020)  -  DOI: https://doi.org/10.3354/dao03441

Ecology, histopathology, and microbial ecology of a white-band disease outbreak in the threatened staghorn coral Acropora cervicornis

Sarah A. Gignoux-Wolfsohn1,*, William F. Precht2, Esther C. Peters3, Brooke E. Gintert2,4, Leslie S. Kaufman5

1Smithsonian Environmental Research Center, Edgewater, MD 21037, USA
2Marine and Coastal Programs, Dial Cordy and Associates, Inc., Miami, FL 33179, USA
3Department of Environmental Science and Policy, George Mason University, Fairfax, VA 22030, USA
4Department of Marine Geology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Virginia Key, FL 33149, USA
5Boston University Marine Program, Boston, MA 02215, USA
*Corresponding author:

ABSTRACT: This study is a multi-pronged description of a temperature-induced outbreak of white-band disease (WBD) that occurred in Acropora cervicornis off northern Miami Beach, Florida (USA), from July to October 2014. We describe the ecology of the disease and examine diseased corals using both histopathology and next-generation bacterial 16S gene sequencing, making it possible to better understand the effect this disease has on the coral holobiont, and to address some of the seeming contradictions among previous studies of WBD that employed either a purely histological or molecular approach. The outbreak began in July 2014, as sea surface temperatures reached 29°C, and peaked in mid-September, a month after the sea surface temperature maximum. The microscopic anatomy of apparently healthy portions of colonies displaying active disease signs appeared normal except for some tissue atrophy and dissociation of mesenterial filaments deep within the branch. Structural changes were more pronounced in visibly diseased fragments, with atrophy, necrosis, and lysing of surface and basal body wall and polyp structures at the tissue-loss margin. The only bacteria evident microscopically in both diseased and apparently healthy tissues with Giemsa staining was a Rickettsiales-like organism (RLO) occupying mucocytes. Sequencing also identified bacteria belonging to the order Rickettsiales in all fragments. When compared to apparently healthy fragments, diseased fragments had more diverse bacterial communities made up of many previously suggested potential primary pathogens and secondary (opportunistic) colonizers. Interactions between elevated seawater temperatures, the coral host, and pathogenic members of the diseased microbiome all contribute to the coral displaying signs of WBD.


KEY WORDS: Coral diseases · 16S sequencing · Acropora cervicornis · White-band disease · Climate change · Microbial ecology · Histopathology · Rickettsiales-like organism · Southeast Florida


Full text in pdf format
Supplementary material
Cite this article as: Gignoux-Wolfsohn SA, Precht WF, Peters EC, Gintert BE, Kaufman LS (2020) Ecology, histopathology, and microbial ecology of a white-band disease outbreak in the threatened staghorn coral Acropora cervicornis. Dis Aquat Org 137:217-237. https://doi.org/10.3354/dao03441

Export citation
Share:    Facebook - - linkedIn

 Previous article Next article