Maine Eelgrass

Zostera sp. in Mussel Ridge Channel, Birch Island, Maine, by Colin Faulkingham, summer 2007

Maine's eelgrass meadows form an important marine and estuarine coastal aquatic habitat. Along with other plants, eelgrass forms the base of food production in the sea. Eelgrass provides shelter for juvenile fish, and invertebrates, is a site for primary settlement of the larvae of some bivalve mollusks and invertebrates, and in certain locations helps to stabilize unconsolidated sediments and shorelines.

Map of eelgrass beds in Maquoit Bay, 1990sVisit our Historical Eelgrass Coverage Viewer to display past eelgrass surveys and change analysis.


Datasets Used by the Viewer

Printable Eelgrass Maps for 11 Maine Coastal Areas, West to East

PDF files may require the free Adobe Reader software (download here) to view or print.

  1. Kittery to Wells - pdf file, 386 kb
  2. Wells to Cape Elizabeth - pdf file, 478 kb
  3. Cape Elizabeth to Small Point - pdf file, 797 kb
  4. Small Point to St. George - pdf file, 816 kb
  5. St. George to Vinalhaven - pdf file, 602 kb
  6. Upper Penobscot Bay - pdf file, 598 kb
  7. Stonington to Mount Desert Island - pdf file, 636 kb
  8. Blue Hill and Frenchman Bays - pdf file, 628 kb
  9. Schoodic Point to Beals Island - pdf file, 568 kb
  10. Beals Island to Cutler - pdf file, 431 kb
  11. Cutler to the St. Croix - pdf file, 440 kb

How Maine Eelgrass Maps Were Made

Between 1992 and 2013, various regions of the coast were flown and photographed. Photography was timed near low tides with low wind velocity, good water clarity, and maximum biomass of eelgrass. These factors aid in the detection of the subtidal portion a bed. Polygons delineating stands of eelgrass were screen digitized and coded using a four category scale of percent cover. Verification was carried out by boat, on foot, and by plane. Though dense patches of eelgrass approximately 6 meters in diameter and less can be identified under good conditions and in some cases were mapped, a conservative estimate of the minimum mapping unit is 150 square meters. This represents a stand of approximately 14 meters in diameter.