Eelgrass Beds 2013

Maine's eelgrass meadows form an important marine and estuarine coastal aquatic habitat for the state. 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 in certain locations helps to stabilize unconsolidated sediments and shorelines. In August 2013, Casco Bay was 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.

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