• Miles of uncrowded white sandy beaches extend to the horizon, separating the clear blue ocean and undulating grass-covered dunes.

    Fire Island

    National Seashore New York

There are park alerts in effect.
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  • Pet Restrictions in Effect March 15 through Labor Day

    Dogs/other pets (except for service animals) are not allowed in the wilderness or on any of Fire Island's federally owned oceanfront beaches from March 15 through Labor Day to help protect threatened and endangered beach-nesting shorebirds. More »

  • Backcountry Camping Permit and Access Procedures

    Reservations for required permits must be obtained through www.recreation.gov. Due to the breach at Old Inlet, access to both east and west wilderness camping zones must now be from Watch Hill or points west, and involve a 1½ to 8 mile hike. More »

  • Attention Watch Hill Ferry Passengers

    Due to channel conditions, delay or cancellation of ferry service between Patchogue and Watch Hill may occur. For updated ferry schedule information, please call 631-475-1665.


Blue mussel washed ashore
Green leaves of salt-marsh grass with a few fleshy reddish plants protrude from the dark, quiet water of a salt marsh. 

The salt marsh provides a nursery ground and home for many invertebrates, including snails (univalves) and small clams (bivalves). 

Fire Island forms an interface between two distinctly different marine environments: the nearshore waters of Atlantic Ocean on its southern border and the Great South Bay and other estuarine environments on its northern exposure.

The estuary is one of the most productive habitats on earth, with its phytoplankton, eelgrass beds and salt marshes. In the Great South Bay, that means home for a variety of sea life. Detritus from the marshes is washed into the bay, where it is used as food by many organisms, including mollusks.

Economically important shellfish include hard-shell clams (Mercenaria mercenaria), soft-shell clams (Mya arenaria), bay scallops (Argopecten irradians), blue mussels (Mytilus edulis) and oysters (Crassostrea virginica). These mollusks are all bivalves. Other bay bivalves include the ribbed mussel (Geukensia demissa) and Morton's egg cockle(Laevicardium mortoni), and the tiny gem shells (Gemma gemma). Univalve mollusks or gastropods in the bay include mud snails (Ilyanassa obsoleta, Littorina littorea) and slipper shells (Crepidula fornicata and C. convexa).

Sunset on beach with wrack.

Shells of mollusks are occasionally washed ashore on the Atlantic beach.

The open water of the Atlantic Ocean along the southern shore of Fire Island does not provide the protection for organisms that is afforded by the less turbulent, estuarine waters of the bay. However, a number of invertebrates—including mollusks—dwell in the sand on the bottom of the continental shelf along Fire Island.

The economically important surfclam (Spisula solidissima) lives on the ocean side of the island. It is harvested far off-shore, but its shells frequently wash onto the beach. You may even see a flock of gulls fighting over one of these live mollusks on the beach. Other ocean mollusks include the bivalve razor clam (Enis directus) and the univalve conch (Busycotypus canaliculatum).


For More Information

A series of Science Synthesis Papers was published in 2005 to support the preparation of a General Management Plan for Fire Island National Seashore.

Additional recent studies and inventories of mollusks on or near Fire Island include:

  • Surf Clam Stock Assessment
    for the Reformulation of the Shore Protection and Storm Damage Reduction Project South Shore of Long Island, New York - Fire Island Inlet to Montauk Point
    February 2002
    U. S. Army Corps of Engineers
  • Intertidal Wetland and Estuarine Finfish Survey of the Backbays, April 2002
    U. S. Army Corps of Engineers
    As a part of the U.S. Army Corps of Engineers (USACE) comprehensive study to identify, evaluate, and recommend longterm measures for hurricane storm damage reduction for the south shore of Long Island, New York from Fire Island Inlet to Montauk Point (FIMP), a number of environmental studies have been completed.

Did You Know?

Seal on beach in winter.

Seals occasionally bask on Fire Island beaches in winter. Enjoy watching them from a safe distance. Remember to give these wild mammals plenty of room to retreat if you encounter one during your winter hike! More...