Spartina Mussel Resilience Project 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 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. 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 Principal investigator 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 Co-investigator 2026

The goals of this project are to try on understand whether Spartina facilitates mussels and mussels, in turn, facilitate Spartina in the face of extreme drought stress. We will assess our hypothesis that Spartina facilitates mussels by shading them with a 2-factored field experiment in which we have small mussel bed transplants (10 mussels arranged in the mud in 20 x 20 cm plots within existing die off areas that are exposed to 4 treatments: with out without Spartina and with or without shading). In each with Spartina plot, we will transplant 10 Spartina stems from adjacent healthy vegetation and in each shading plot, we will install a 25 x 25cm shade made out of nylon shade cloth and pvc corner posts. To assess our second hypothesis that mussels in turn facilitate Spartina by reducing the rate at which water evaporates from the marsh surface (and therefore reduces salt build up in the sediment) we will conduct a second experiment in which we manipulate the presence of mussels and water availability to Spartina transplants (as above) deployed in die off areas. Each Spartina transplant will be assigned one mussel treatment (with or without mussels) and one level of water (ambient water or water addition). Mussel addition treatments will be established by interspersing 10 mussels among Spartina stems and water addition treatments achieved by adding 1 gallon of water to each transplant every other day from July 1- September 15th.

Question 2: How do the spatial and temporal patterns of biogeochemical processes, primary production, community dynamics, decomposition, and disturbance vary across the estuarine landscape, and how do they relate to environmental gradients? (more information)

marsh biomass nutrients salinity temperature LTER NSF GCE crustaceans plants Spartina disturbance patterns invertebrate ecology plant ecology Overall geographic extent of the research project -81.307978 -81.176185 31.536369 31.380150 2011-06-28 2012-04-30

NSF Predoctoral Fellowship to Christine Holdredge

estuary marsh complex Sapelo Island - Sapelo Island on the Southeast Georgia Coast -81.307978 -81.176185 31.536369 31.380150 GIS file (ArcGIS shapefile) https://gce-lter.marsci.uga.edu/private/registration/files/GIS/GCE-13-2011_GIS_Export.zip Map (Google Earth KML/KMZ or map image) https://gce-lter.marsci.uga.edu/private/registration/files/Maps/GCE-13-2011_Maps_Mussel_Resiliency_Study.kml

We are hoping to set this project up on Lighthouse road about 500 yards south of the intersection of Beach and Lighthouse roads but have alternative sites.

There will be 16- 25 x 25cm x 40cm (length x width x height) shades constructed out of shade cloth and pvc poles and Spartina transplants (extracted from adjacent healthy vegetation and put into die off areas)

Spartina transplants (48 20 x 20cm transplants) will be collected and 480 mussels.