Biodiversity Layer

Description & Instructions

The Biodiversity layers included in the Planners Maps were created by the Maine Natural Areas Program with support from the Downeast Conservation Network as part of a resilience mapping study depicting conservation values for terrestrial, coastal and inland aquatic ecosystems for Washington and Hancock Counties in Maine. The Biodiversity layer includes four sub-layers listed below.

To use the layer, check the box to turn it on. Expand it by clicking the triangle and turn on a desired sub-layer. Click on a polygon of interest to access co-occurrence scores. The popup window will reveal the total score and each of the values contributing to the score.

To learn more about an individual sublayer, right click on the title of the sublayer in the Contents window and choose Description.

Biodiversity Layers

Terrestrial Co-occurrence: This layer represents the summed weighted values of rare plant locations, natural communities, listed animals, significant wildlife habitats, undeveloped habitat blocks and riparian zones co-occurring in Maine’s Hancock and Washington Counties.

Coastal Co-occurrence: This is a co-occurrence model result of summed weighted feature attributes along the coasts of Hancock and Washington Counties. The features and their weighted values are as follows:

      • Seabird Nesting Islands – 3
      • Essential Tern Habitat – 3
      • Shorebird Feeding and Roosting Areas – 3
      • Tidal Wading Bird & Waterfowl Habitat – 2
      • Threatened Animal Species – 2
      • Animal Species of Special Concern – 1
      • Seal Haul-outs – 1
      • Shellfish Beds (8 species) – 1
      • Seed Mussel Conservation Areas – 1
      • Marine Worm Flats – 1
      • Historic Cod and Haddock Spawning Areas – 1
      • Eelgrass Beds – 1
      • Exemplary Natural Communities (S3) – 3
      • Critically Imperiled Plants (S1) – 3
      • Imperiled Plants (S2) – 2
      • Rare Plants (S3) – 1


Co-occurrence of aquatic habitat values for Hancock and Washington Counties, ME using 1-24k flowlines as a base. Co-occurrence layers include:

      • Shortnose sturgeon
      • Atlantic sturgeon
      • Sea run brook trout
      • Alewife blueback herring
      • American shad
      • American eel
      • Atlantic salmon
      • Brook trout
      • Endangered, threatened and special concern aquatic animal spp. (ETSC)


Aquatic Co-Occurrence: All elements contribute a value of 1 except for ETSC which contributes 3 for Endangered spp., 2 for Threatened spp. and 1 for special concern spp. Condition of NHD 24k flowlines, split into 1 km lengths. Condition values are a mean of the Designing Sustainable Landscapes index of ecological integrity score scaled to the State of Maine and the quantile rank (rescaled 0-1) of the full connected length of the stream/river network between barriers. Barriers included were dams, unknown/unsurveyed road crossings (inclusive of all unknown barriers on private lands for which data is not publicly available), and barriers confirmed by survey. Credits: U.S. Geological Survey in cooperation with U.S. Environmental Protection Agency, USDA Forest Service, and other Federal, State and local partners (see dataset specific metadata under Data_Set_Credit for details).