Award: OCE-1445834

From a research perspective, the goals of this project were to answer the following three questions through experiments and comparative studies: 1) Is grazer facilitation of fungal disease in marine plants a common but overlooked interaction? 2) What is the resultant impact of grazer-facilitated fungal infection on marine plant growth 3) How do multiple stressors (i.e., warming, drought, eutrophication) impact the strength of grazer facilitation of fungal disease in marine plants? For outreach, my goals were to generate a field course that involves high school students, work with The Nature Conservancy to incorproate my results into conservation plans, and integrate plant-grazer-disease interactions into my marine lectures and two edited books for graduate-level education. Over the past 5 years, I have been very succesful in accompishing all of the goals set out in this proposal. We found that mesograzers commonly faciliate microbial infection in marine foundation species across a diverse suite of ecosystems (seagrasses, salt marshes, corals, mangroves, kelps and macroalgae), that this infection suppresses plant growth, and that commonly occuring stressors in the marine system increase, and do not dampen this interaciton. This leads to increasing physical stress resulting in increased infection and decreased growth in marine foundation species when grazers are present. This pattern was consistent in both North and South America, where we work in almost all of the above mentioned ecosystems We published over 30 peer-reviewed articles as a result of funding from this grant. This includes 4 in Proeedings of the National Academy of Science, 1 in Science, 2 in Ecology Letters, and over 10 in outstanding marine based journals. Our work has been featured in Science, The Washington Post, The NYTIMES, The Boston Globe, Regional newspapers such as the Charlotte Observer, and online on Science Daily, Nature Climate Change, and on the radio on local and national NPR stations, and on the BBC. In addition, I co-edited 3 graduate level text books with support from this grant. One of those books, Marine Community Ecology and Conservation, is the leading gradaute level text book in marine ecology in the world. Seven graduates students were trained and in part supported on this grant, as well as 10 undegraduate students and 3 post doctoral scholars. One of those graduate students and 3 post-doctoral scholars have matricluated into faculty positions. 14 of the papers published had students as lead author, and 4 of those were undegraduates. 28 of the papaers had students as co-authors. Work produced as a result of funding from this grant has changed they way we think about disease in marine systems. It has shown that marco food webs in large way control microbial communities that attack foundation plants and that conserving predators can protect plants from disease. This overturns the idea that microbial diseases are mostly controlled from the bottom-up. I have also shown the positive interactions like these and many others will greatly increase efficiency in conservation and restoraion. Most applicable to immediate human needs, this project funded work that helped determine the causes of die-off in seagrasses and salt marshes, economically important ecosystems to humans. In addition, work produced with funds from this grant helped decipher the impacts of the deepwater horizon oil spill on gulf coast salt marsh ecosystems. It was this work that allowed the state of Louisiana to present a strong case showing permenant loss of natural resources as a direct result of the oil spill. Last Modified: 08/10/2017 Submitted by: Brian R Silliman