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Award Detail

Doing Business As Name:Georgia Tech Research Corporation
  • Mark E Hay
  • (404) 894-8429
Award Date:09/13/2009
Estimated Total Award Amount: $ 1,204,987
Funds Obligated to Date: $ 1,204,987
  • FY 2009=$1,204,987
Start Date:09/15/2009
End Date:08/31/2014
Transaction Type:Grant
Awarding Agency Code:4900
Funding Agency Code:4900
CFDA Number:47.050
Primary Program Source:040100 NSF RESEARCH & RELATED ACTIVIT
Award Title or Description:Killer Seaweeds: Allelopathy against Fijian Corals
Federal Award ID Number:0929119
DUNS ID:097394084
Parent DUNS ID:097394084

Awardee Location

Street:Office of Sponsored Programs
Awardee Cong. District:05

Primary Place of Performance

Organization Name:Georgia Institute of Technology
Street:225 NORTH AVE NW
Cong. District:05

Abstract at Time of Award

Coral reefs are in dramatic global decline, with reefs commonly converting from species-rich and topographically-complex communities dominated by corals to species- poor and topographically-simplified communities dominated by seaweeds. These phase-shifts result in fundamental loss of ecosystem function. Despite debate about whether coral-to-algal transitions are commonly a primary cause, or simply a consequence, of coral mortality, rigorous field investigation of seaweed-coral competition has received limited attention. There is limited information on how the outcome of seaweed-coral competition varies among species or the relative importance of different competitive mechanisms in facilitating seaweed dominance. In an effort to address this topic, the PI will conduct field experiments in the tropical South Pacific (Fiji) to determine the effects of seaweeds on corals when in direct contact, which seaweeds are most damaging to corals, the role allelopathic lipids that are transferred via contact in producing these effects, the identity and surface concentrations of these metabolites, and the dynamic nature of seaweed metabolite production and coral response following contact. The herbivorous fishes most responsible for controlling allelopathic seaweeds will be identified, the roles of seaweed metabolites in allelopathy vs herbivore deterrence will be studied, and the potential for better managing and conserving critical reef herbivores so as to slow or reverse conversion of coral reef to seaweed meadows will be examined. Preliminary results indicate that seaweeds may commonly damage corals via lipid- soluble allelochemicals. Such chemically-mediated interactions could kill or damage adult corals and produce the suppression of coral fecundity and recruitment noted by previous investigators and could precipitate positive feedback mechanisms making reef recovery increasingly unlikely as seaweed abundance increases. Chemically-mediated seaweed-coral competition may play a critical role in the degradation of present-day coral reefs. Increasing information on which seaweeds are most aggressive to corals and which herbivores best limit these seaweeds may prove useful in better managing reefs to facilitate resilience and possible recovery despite threats of global-scale stresses. Fiji is well positioned to rapidly use findings from this project for better management of reef resources because it has already erected >260 MPAs, Fijian villagers have already bought-in to the value of MPAs, and the Fiji Locally-Managed Marine Area (FLMMA) Network is well organized to get information to villagers in a culturally sensitive and useful manner. The broader impacts of this project are far reaching. The project provides training opportunities for 2-2.5 Ph.D students and 1 undergraduate student each year in the interdisciplinary areas of marine ecology, marine conservation, and marine chemical ecology. Findings from this project will be immediately integrated into classes at Ga Tech and made available throughout Fiji via a foundation and web site that have already set-up to support marine conservation efforts in Fiji and marine education efforts both within Fiji and internationally. Business and community leaders from Atlanta (via Rotary International Service efforts) have been recruited to help organize and fund community service and outreach projects in Fiji -- several of which are likely to involve marine conservation and education based in part on these efforts there. Media outlets (National Geographic, NPR, Animal Planet, Audubon Magazine, etc.) and local Rotary clubs will be used to better disseminate these discoveries to the public.

Publications Produced as a Result of this Research

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Rasher DB and ME Hay "Seaweed allelopathy degrades the resilience and function of coral reefs." Communicative and Integrative Biology, v.3, 2010, p..

Rasher DB, ME Hay "Competition induces allelopathy but suppresses growth and anti-herbivore defence in a chemically rich seaweed" Proceedings of the Royal Society B, v.281, 2014, p.20132615. doi: 

Dell CLA, Montoya JP, Hay ME "Effect of marine protected areas (MPA) on food web integrity: MPA fish feed higher in the food chain." Marine Ecology Progress Series, v.540, 2015, p.227. doi:10.3354/meps11487 

Bonaldo RM, ME Hay "Seaweed-coral interactions: variance in seaweed allelopathy, coral susceptibility, and potential effects on coral resilience" PLoS ONE, v.9, 2014, p.e85786. doi:doi:10.1371/journal.pone.0085786 

Hay ME and DB Rasher "Coral reefs in crisis: reversing the biotic death spiral." Faculty 1000 Biology Reports 2010, v.2, 2010, p..

Rasher DB and ME Hay "Chemically rich seaweeds poison corals when not controlled by herbivores." Proceedings of the National Academy of Sciences of the USA, v.107, 2010, p.9683. 

Rasher DB and ME Hay "Chemically rich seaweeds poison corals when not controlled by herbivores." Proceedings of the National Academy of Sciences., v.107, 2010, p.9683. 

Shearer, TL, DB Rasher, TW Snell, ME Hay "Gene expression patterns of the coral Acropora millepora in response to contact with macroalgae." Coral Reefs, v.31, 2012, p.1177-1192. doi:10.1007/s00338-012-0943-7 

Andras TD, TS Alexander, A Gahlena, RM Parry, FM Fernandez, J Kubanek, MD Wang, and ME Hay "Seaweed allelopathy against coral: surface distribution of seaweed secondary metabolites by imaging mass spectrometry." Journal of Chemical Ecology, v.38, 2012, p.1203-1214. doi:10.1007/s10886-012-0204-9 

Shearer TL, TW Snell, ME Hay "Gene Expression of corals in response to macroalgal competitors" PLoS ONE, v.9, 2014, p.e114525. doi:doi:10.1371/journal.pone. 0114525 

Rasher DB, A Hoey, and ME Hay "Consumer diversity interacts with prey defenses to drive ecosystem function." Ecology, v.94, 2013, p.1347. doi: 

Beattie AJ, ME Hay, B Magnusson, R de Nys, J Smeathers, JFV Vincent "Ecology and bioprospecting." Austral Ecology, v.36, 2011, p.341. doi:10.1007/s00442-011-2174-y 

Dixson DL and ME Hay "Corals chemically cue mutualistic fishes to remove competing seaweeds" Science, v.338, 2012, p.804-807. doi:10.1126/science.1225748 

Gibbs DA, ME Hay "Spatial patterns of coral survivorship: Janzen-Connell effects versus other drivers of localized mortality for brooding corals" Peer J, v., 2015, p.. doi: 

Hay ME, Rasher DB "Corals in crisis" The Scientist, v.24, 2010, p.42.

Dixson DL, D Abrego, ME Hay "Chemically-mediated behavior of recruiting corals and fishes: a tipping point that may limit reef recovery" Science, v.345, 2014, p.892.

Clements CS and Hay ME "Competitors as accomplices: seaweed competitors hide corals from predatory starfish." Proceedings of the Royal Society B, v., 2015, p.. doi: 

Hay ME "Challenges and opportunities in marine chemical ecology" Journal of Chemical Ecology, v.40, 2014, p.216. doi:DOI 10.1007/s10886-014-0393-5 

Vergés A, PD Steinberg, ME Hay, AG Poore, AH Campbell, E Ballesteros, KL Heck Jr., D Booth, MA Coleman, D Feary, W Figueira, T Langlois, EM Marzinelli, T Mizerek, PJ Mumby, Y Nakamura, M Roughan, E van Sebille, A Sen Gupta, DA Smale, F Tomas, T Wernberg, "The tropicalisation of temperate marine ecosystems: Climate-mediated changes in herbivory cause community phase shifts" Proceedings of the Royal Society B, v.281, 2014, p.20140846. doi: 

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