EAGER: Are coral diseases contagious?

Florida Institute Of Technology, Melbourne FL

Investigators

Abstract

Diseases are believed to be one of the greatest threats to corals in the Caribbean. Yet, very little is known about marine diseases in general and coral diseases in particular. Identifying coral pathogens has proven difficult and evasive and many coral diseases are assumed to be infectious, suggesting that infection is caused by pathogens being passed from colony to colony. However, few studies have tested this assumption and this project will incorporate spatial epidemiology, or disease mapping, to provide insight into whether diseases cluster and follow a contagious-disease model. This will be accomplished by using a hierarchical sampling design over two spatial scales in the Caribbean. The study will also incorporate locations with and without a recent history of frequent thermal stress to also test the alternate hypothesis that coral diseases are not infectious but are the result of secondary effects due to thermal stress such as the increase of opportunistic pathogens from the normal flora of the coral or compromised coral immune systems. This approach will be combined with experiments to examine whether coral diseases are indeed transmissible. There is great urgency to identify coral diseases, predict their prevalence, and determine whether they are infectious or not. This project will help provide an understanding of the etiology of coral diseases, which can then inform us whether human intervention will help reduce their prevalence and negative outcomes. Although microbes play a role in coral disease, many coral diseases might not be transmissible. Therefore, we also need to incorporate environmental threshold parameters, which may be more likely as an underlying mechanism driving coral-disease dynamics. The results will have important implications for modeling diseases and predicting contemporary and future coral disease outbreaks. The Broader Impacts of this proposal are potentially transformative with regards to our understanding of coral disease by taking a spatial ecology and epidemiological approach. The principal investigator will train underrepresented groups in coral reef biology and ecology as well as train a Ph. D. level graduate student during this project. Additionally, the principal investigator will conduct public outreach activities on the importance of coral reef ecosystem services.