Spartina Mussel Mesocosm Experiment Dr. Christine Angelini University of Florida

Department of Environmental Engineering Sciences University of Florida Gainesville Florida 32611 USA

christine.angelini@essie.ufl.edu http://www.angeliniecologylab.com/the-lab.html https://orcid.org/0000-0002-6669-5269 Georgia Coastal Ecosystems LTER Project

Dept. of Marine Sciences University of Georgia Athens Georgia 30602-3636 USA

gcelter@uga.edu https://gce-lter.marsci.uga.edu/ Dr. Christine Angelini University of Florida

Department of Environmental Engineering Sciences University of Florida Gainesville Florida 32611 USA

christine.angelini@essie.ufl.edu http://www.angeliniecologylab.com/the-lab.html https://orcid.org/0000-0002-6669-5269 Principal investigator Dr. Brian R. Silliman Duke University

135 Duke Marine Lab Rd. Duke University Marine Lab Beaufort North Carolina 28516-9721 USA

brian.silliman@duke.edu https://nicholas.duke.edu/people/faculty/silliman https://orcid.org/0000-0001-6360-650X Co-investigator Dr. John Griffin University of Swansea

Department of Biosciences University of Swansea Swansea SA2 8PP Wales, United Kingdom

J.N.Griffin@swansea.ac.uk http://www.sillimanlab.com/people-griffin.php Co-investigator 2026

The proposed project aims to experimentally simulate a drought in mesocosms with the goal of understanding how ribbed mussels might influence Spartina's resilience to drought stress. To accomplish this, we plan to extract 24, 50 x 50 x 30 (L x W x D) transplants of mud and Spartina from the marsh at Dean creek (half of the transplants will also contain natural mussel mounds- the size of plots are this size to allow us to extract small mussel mounds from the marsh) and place them in plastic tubs. These tubs will them be arranged in the experimental ponds behind the UGAMI institute and we will then apply drought and no-drought treatments to assigned plots. Drought treatments will simulate conditions observed during the 2009 drought that caused Spartina to die back in marshes on Sapelo (i.e. periods of ~ 2weeks with neither simulated tidal inundation or precipitation). No- drought treatments will receive the same simulated tidal regime but receive fresh water additions every 3rd day to mimic natural rainfall. Spartina stem survival will be scored weekly for the 12-week duration of the experiment. At the end of the experiment, all transplants will be returned to their original holes in the marsh.

marsh salinity temperature LTER NSF GCE crustaceans Geukensia infauna plants Spartina disturbance patterns invertebrate ecology plant ecology Overall geographic extent of the research project -81.299522 -81.264378 31.398877 31.371003 2012-06-12 2012-09-12

None

estuary marsh complex Dean Creek - Doboy Sound/salt marsh site at the southern end of Sapelo Island near Dean Creek and the Sapelo lighthouse. A few small creeks are present, but a large creek (Dean Creek) is easily accessed. Upland is composed of small hammocks and some constructed causeways, with sand dune complexes east of Dean Creek and extending to the beach. Upper end of the watershed is affected by a culvert at Beach Road and heavy student use of marsh immediately adjacent to culvert. A hydrographic sonde is deployed in Doboy Sound near Commodore Island approximately 1.5km from this site. GCE6 is also the focus of Sapelo Island Microbial Observatory research on microbial diversity and genomics (http://simo.marsci.uga.edu) -81.299522 -81.264378 31.394072 31.371003 UGA Marine Institute - The University of Georgia Marine Institute is located on the southern end of Sapelo Island, a barrier island off the central Georgia coast. -81.282950 -81.278834 31.398877 31.395295

Transplants will be extracted from Dean Creek marsh and the experiment will take place in the experimental ponds behind the institute. We plan to coordinate using this space with researchers from the Pennings and Craft labs

Yes- Spartina and ribbed mussels will be collected for the mesocosms but returned at the end of the experiment