Shellfish polygons were digitized from hand drawn polygons representing hardclam, softclam, and oyster beds produced by the Department of Agriculture from their records in 1990 (approximately). The data is general in its nature and should be used only as a guide.This layer should not be construed to depict the actual, absolute locations of any shellfishing resources. Use this layer with other 1:24,000-scale map data such as the Coastal Boundary, Town Boundaries, Roads and Trails, Airports, Railroads and other base map data derived from the USGS 7.5 minute topographic quadrangle maps and compiled at a 1:24000 scale.