Oyster Reef Mapping with Reach RS

Researchers from the Marine Robotics and Remote Sensing (MaRRS) Lab at the Duke University Marine Lab are using UAS and satellite imagery to assess and conserve local wetland and oyster habitats along the coast of North Carolina, USA with the immense help of the Emlid Reach RS in the field.

For a project funded by North Carolina Space Grant and North Carolina Sea Grant, MaRRS Lab researchers are currently developing oyster health indicators using drone imagery that coastal managers can use to effectively and efficiently monitor oyster reef health, which previously has involved large amounts of time and resources to perform. Drone flights conducted over local oyster reefs collected hundreds of overlapping individual images that were stitched together to create an orthomosaic and digital elevation model of the reefs. In order to accurately geolocate mapping products, ground control points (GCPs) were installed in the field. The Emlid Reach RS was used to take highly precise X,Y, and Z locations of each GCP to accurately georeference the orthomosaic and digital elevation model produced from the drone photos.

The receiver was also used to perform traditional oyster reef monitoring methods that are being used to assess the accuracy of new drone methodologies. Reef area was calculated by using RTK unit to collect highly accurate continuous measurements of the perimeter of a distinct reef patch. Additionally, Reach RS was used to estimate mean reef height by taking highly accurate elevation measurements along the reef crest.

MaRRS researchers have also used the Reach RS to aid in data collection for an accuracy assessment of wetland habitat classifications of the Rachel Carson Reserve in coastal North Carolina. The Reach RS was brought into the field to collect sample points of habitat types that were then easily uploaded as shapefile points into ArcGIS to act as verification samples for the satellite imagery-based classification of the Reserve.

Emlid receiver has proved to be an efficient means of surveying out in the field. A hotspot is used to connect the receiver via Wifi and GPS data is easily collected with a smartphone through the Emlid surveying application page. From the soft muddy substrate of coastal wetlands to the rough oyster reef patches of the intertidal zone, the environmentally-sealed Reach RS has been reliable in all elements to accurately document and record field samples needed to perform the important research on coastal monitoring being done by the MaRRS Lab research team at Duke University.

Emlid team wants to say thank you to Duke Marine Robotics and Remote Sensing Lab and particularly to Anna Windle for sharing this project. All photos are courtesy of Duke Marine Robotics and Remote Sensing Lab.