Sapelo Research Application Form
Research Application ID: GCE-74-2016 (submitted: 04/07/2016, status: approved)
Provide a brief title for web display
Marsh Nekton Exclusion
Investigator Information
On Island Sponsor: GCE SINERR UGAMI GADNR
| Principal Investigator: | Brian R. Silliman | ||
| Home Institution: | Duke University | ||
| Award Information: | (not specified) | ||
| Mailing Address: | 135 Duke Marine Lab Rd. | Phone Number: | (352) 392-1137 |
| Duke University Marine Lab | E-mail Address: | brian.silliman@duke.edu | |
| Beaufort, North Carolina 28516-9721 | |||
| Co-investigators: | Steven C. Pennings (University of Houston), Jacob Shalack (University of Georgia Marine Institute), Joe P. Morton (Duke University Marine Lab), Qiang He (Duke University Marine Lab), Stacy Zhang (Duke University Marine Lab), James Byers (University of Georgia) | ||
Briefly describe the project goals and methodology
We will test the hypothesis that nekton exert control over salt marsh structure and function. To test this, we will install a long-term, field experiment that excludes all large nekton from salt marsh areas. We will identify 24 marsh areas in the intermediate-height Spartina zone of similar elevation and distance from tidal creek and upland areas. In 8 of those areas, we will install circular, vexar nekton exclusion cages (1 meter tall, 6mm mesh, 5 m diameter). Another 8 plots will be uncaged controls with their perimeter marked by 6 wooden marking posts (4 ft x 1in). Cage controls will consist of 8 partial cages constructed in the manner described previously but with two 2.5 m gaps in the perimeter allowing for the free passage of nekton.
Where will the project be located?
The project will be installed in a mid-marsh area of lighthouse marsh on the southern end of Sapelo Island (31°23'21.9"N 81°16'39.2"W).
How will you provide GPS coordinates for study sites?
GPS coordinates are listed in the project location field
What are the expected start and end dates of the project?
Start Date: 07/01/2016 End Date: (ongoing)
How many people will access the site and at what frequency?
After the plots are established, a single person will visit the site weekly to ensure that cages are well-maintained and make repairs if necessary. Several people (6-10) will access the site for 5 days every quarter to monitor the results of the experiment.
Please list keywords (as many as are appropriate) that describe your project:
What equipment will be deployed in the field?
We will deploy 16 circular predator exclusion cages composed of 4 mesh, vexar cloth. Each cage will be 1.2 m tall and 5 m in diameter. Cages will be held in place by 8 - 6ft PVC posts affixed to the outer vexar cage wall with zip ties. Post will be driven into the marsh substrate ~2.5 ft such that the bottom edge of the cage wall will be embedded in the sediment. Finally, 1 ft high wooden legs will be installed inside each plot to accommodate a small, movable aluminum platform that will be deployed when we are working at the site and removed otherwise.
Will plants or animals be collected as part of this study?
Yes, we will collect small numbers of plants and animals each quarter under the UGAMI collection permit.
What are the likely impacts of the project on the site?
The initial installation of exclusion cages will disturb approximately 36 square meters in the intermediate Spartina zone, plus associated trampling. PVC stakes and wells for pore water sampling will occupy less than 2 square meters of marsh surface. Wrack accumulation around cage perimeters will be minimized through periodic maintenance and removal. Enclosures may have a small effect on local hydrology (flow) for the duration of the experiment. Flow conditions are expected to return to normal following the completion of the experiment and the removal of structures. There is expected to be some trampling of marsh vegetation during monitoring of the project. We will create trails through tramping of the area directly around plots. We expect the area to fully revegetate 1-2 years after the experiment is terminated.
Will the project design include boardwalks? If not, explain why not.
No. We will access plots using a movable aluminum platform (6 ft long x 1 ft wide) that will be deployed on wooden legs (1 ft high) that will be installed inside each plot. A similar temporary aluminum platform will be deployed at the access point to each plot as needed. In both cases, the aluminum platforms will be deployed when we are working at the site and removed otherwise.
How long will impacts persist after the research is concluded?
All materials will be removed from the marsh site when the experiment is concluded. We expect the area disturbed through experimental manipulation and tramping by researchers to have largely recovered in 1-2 years.
Research Permits:
Georgia DNR Coastal Resources Division: GCE-74-2016_Permit_LOAck-Sillimann_Marsh_Nekton_Research_7.11.16 (07/01/2016-indefinite)
Study Area Map:
Files attached to this application
GCE-74-2016_Maps_Exclusion_Cages.kml (KML file, 1.51 kb, submitted 05/06/2016)
[web link: https://gce-lter.marsci.uga.edu/private/registration/files/Maps/GCE-74-2016_Maps_Exclusion_Cages.kml]