Site Summary: Site Summary: Brewster - Eastham Flats

Map for the Brewster - Eastham Flats IBA site

Nominated By:

Blair Nikula


4,200 acres

Towns and Counties:

Brewster, Eastham; Barnstable


towns of Brewster, Orleans, and Eastham, private

Major Habitats:

20% salt marsh, 10% coastal beach, 70% marine/tidal

Land Use:

recreation or tourism, fisheries/aquaculture, undeveloped

Minor Threats:

disturbance to birds or habitat, recreational development/overuse

Site Description:

The Brewster - Eastham Flats extend from approximately Quivett Creek on the Brewster/Dennis town line northeastward to First Encounter Beach in Eastham. The area includes approximately 9.7 linear miles of shoreline and over 3,500 acres of tidal flats. Also included are almost 600 acres of salt marsh, primarily in the First Encounter, Boat Meadow Creek, and Namskaket areas. Small areas of coastal dune are also included.

Current Conservation Status:

Recreational use by bathers, boaters, and, especially in recent years, jet-skiers creates disturbance during the summer months, though it is not clear to what extent this disturbance is impacting birds. The period of greatest bird use appears to be in the fall, when human use is minimal. Residential development in upland areas bordering the proposed IBA has been extensive, but what if any impact this is having on the flats or salt marsh is unknown.

Ornithological Significance:

This site annually hosts large concentrations of Brant, with numbers routinely exceeding 2,000 birds and occasionally exceeding 3,000 (CBC data). Large numbers of shorebirds, particularly Black-bellied Plovers, Sanderlings, and Dunlins, use the area during fall migration and early winter. Although the size of the area makes censusing difficult, and no systematic shorebird counts have been conducted here, the number of shorebirds using the area easily numbers into the thousands.

Other Important Species:



Maximum Numbers


Dunlin Fall/Winter 1,000-1,500+ 1990-2001
Brant Fall/Winter 2,000-3,000+ 1990-2001

Other Flora or Fauna of Significance:

The flats have historically been the site of standings of marine mammals, primarily White-sided Dolphins Northern Pilot Whales, and cold-stunned sea turtles (Ridley's, Green, Loggerhead). Commercially significant populations of shellfish and finfish are also present.

Data Sources:

Christmas Bird Counts, Bird Observer records

Blair Nikula, personal observations

Download the Map:

brewstereastham-iba.jpg 526.51 kB