Peconic Bay

The Peconic Bay is the parent name for two bays between the North Fork and South Fork of Long Island in the U.S. state of New York. It is separated from Gardiners Bay by Shelter Island.

Peconic Bay is divided by Robins Island into the Great Peconic Bay on the west and Little Peconic Bay on the east. Great Peconic is a shallow bay, less than 30 feet (9 m), while Little Peconic can have depths over 80 feet (25 m). The west end of Great Peconic Bay is also called Flanders Bay. The Shinnecock Canal provides access from the Great Peconic Bay to Shinnecock Bay. The two Peconic Bays are often collectively referred to as "the Peconics".

The Peconics are a tidal estuary system fed at the western end by the Peconic River. Other notable tidal estuary creeks which provide brackish water to the system are Meeting House Creek, Brushes Creek, James Creek, and Deep Hole Creek on the North Fork. These and others bring lesser salinity to the water compared to the Atlantic Ocean. For that reason, the clams, oysters and bay scallops were numerous for generations since they require brackish water and the bountiful phyto and zooplankton which give the system its first tier of life. Reseeding of shellfish in 2005 and 2006 and leasing of the bottom to commercial farmers for clams and oysters have given rise to hope for the ecosystem.