Current Maine Tidal Marshes Map

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Data Description and Usage

This feature class was created to document tidal marsh natural communities for use in status assessment, species management, and habitat conservation of rare plant species and rare and exemplary natural communities and ecosystems in Maine. Features were digitized using best available low tide aerial imagery in 2013 and 2014. A subset of mapped marshes were field verified and classified using Natural Landscapes of Maine (Gawler and Cutko 2010) . Other tidal marshes were classified based on proximity to field verified features. The minimum mapping unit for tidal marshes was 5 acres though most, but not all marshes between 2.5 and 5 acres were also included.

Data Disclaimer

These data are meant to help inform decisions at the local, regional, and state-level for coastal conservation and management planning. Users must assume responsibility in determining the usability of this data for their purposes. Metadata is included for all of the downloadable layers and should be reviewed for more specifics on how these data were created. Neither the Maine Natural Areas Program, the Maine Geological Survey nor the Department of Agriculture, Conservation and Forestry, nor its employees or agents: (1) make any warranty, either expressed or implied for merchantability or fitness for a particular purpose, as to the accuracy or reliability of the information shown on the map; nor are they (2) liable for any damages, including consequential damages, from using the map or the inability to use the map.

Digital Data

The 2014 tidal marsh layer can be downloaded as a shapefile (ZIP 1.9MB) for use in any GIS software to perform further spatial analysis.

Related Data

Tidal Marsh Migration
Coastal Undeveloped Habitat Blocks with 1 meter of Sea Level Rise

Frequently Asked Questions

Does the Maine Tidal Marsh Data include only saltwater tidal marshes?

The Maine Tidal Marsh data displays marshes of all tidal types, including saltwater, brackish, and freshwater tidal. These correspond with the MNAP natural community classifications of Spartina Saltmarsh, Mixed Graminoid - Forb Saltmarsh, Brackish Tidal Marsh, and Freshwater Tidal Marsh.

More Help

Contact the Maine Natural Areas Program at

Updated: 10/4/2016