Integrating the use of Unoccupied Aircraft Systems (UAS) into Coastal Land Management Strategies on the Outer Banks of North Carolina

Abstract

Unoccupied aerial systems (UAS) stand to dramatically improve the way coastal managers understand and plan for climate change, yet the tool has been underutilized for this purpose. The Duke Marine Robotics and Remote Sensing Lab and the North Carolina chapter of The Nature Conservancy (TNC) collaborated to develop a series of research questions and methods using UAS to assess the effects of climate change at the Nags Head Woods Preserve (NHW), a coastal property TNC manages on the Outer Banks. We aimed to better understand 1) the history of shoreline erosion and 2) the likely climate-driven ecological changes at the site. High-resolution imagery was captured using an eBee Plus fixed wing drone and images were stitched into a single mosaic using Pix4D. Long-term shoreline erosion rates were calculated and interpreted by evaluating shoreline characteristics apparent from UAS imagery. The NHW shoreline has exhibited significant erosion, which varies spatially due mainly to differences in shoreline type and orientation. Ecological vulnerability to climate change could not be assessed without setting high-accuracy baselines for the present-day areal extent of plant communities within NHW. Training data were generated from UAS imagery and used to run a supervised classification, resulting in the first accurate delineation of each plant community in NHW. These methods may be repeated in the future to assess climate-driven ecological change through time. UAS proved to be an effective tool for organizations and managers to improve research and monitoring in the coastal environment.