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CREST

Research: Coral Disease

For more images of coral diesease see: Black-Band Disease and Coral Bleaching galleries.
White band disease on Acropora palmata (Elkhorn coral) in the Virgin Islands National Park. Photo credit: Ginger Garrison, USGS. [larger version]	Black band disease affecting Diploria strigosa (brain coral). Photo credit: Ginger Garrison, USGS. [larger version]
White plague disease affecting Montastraea cavernosa (great star coral). Photo credit: Ginger Garrison, USGS. [larger version]	Yellow blotch/band disease on Montastraea cavernosa (great star coral). Photo credit: USGS. [larger version]

Coral diseases were first reported on reefs in the Florida Keys and Caribbean in the 1970s. In the decades since, they have been reported worldwide and with increasing frequency. Disease is now recognized as one of the major causes of reef degradation and coral mortality. Recent research has suggested that coral diseases may be secondary opportunistic infections, rather than the result of primary pathogens, making it imperative to understand the microbial shifts that accompany the transition from healthy to diseased corals. Additionally, we need to determine if the spread of coral disease is affected by the level of connectivity among water masses, organisms, trophic levels, or habitats. See black-band disease and coral bleaching galleries.

We will investigate coral disease processes and causes by characterizing microbial communities in diseased and healthy representatives of selected coral species both temporally and spatially by employing microarray technology. We are investigating the diagnostic potential of coral fluorescence for identifying disease-induced physiological stress. In the laboratory, experiments test the possibility that the spread of coral diseases are enhanced by micronutrient inputs from atmospheric deposition (e.g. iron in African dust). This work links coral ecosystem studies in marine protected areas to better understand coral ecosystem health.

Specific efforts will include:

• Comparing microbial communities between diseased and healthy corals from two species in two National Parks: Dry Tortugas National Park and Virgin Islands National Park.
• Utilizing new microarray technology (representing 30,000 microbial taxa) to get a taxonomic overview of the shifts in microbial communities between healthy and diseased corals, between species of corals, and between different geographic areas
• Validating a method to preserve coral-associated microbial samples for shipment without the need for liquids or cold temperatures
• Conducting laboratory experiments with identified coral pathogens to determine if exposure to atmospheric dust components affects the growth rate or toxin-production of the pathogens.
• Assisting the development and curation of an international database of coral microbiology data
• Field testing a new technique to determine if coral fluorescence can be used to remotely assess coral health