Polygons of submerged aquatic vegetation (SAV) were delineated from photo signatures identified on 4-band orthophotography. Ground truthing was done after initial delineations were completed. Ground truthing was done by boat using underwater video equipment and GPS. Final delineation and GIS database development was done using ground truth information. Over 187 delineations of eelgrass and widgeon grass were made, totaling 1,144 acres. Source imagery was collected on behalf of the Rhode Island Eelgrass Mapping Task Force and are available via RIGIS.
The mapping was done as part of the 3-tiered approach to mapping and monitoring SAV as described by Neckles et al., 2012.