Deer Creek Marsh Wildlife Management Area is an 1,195-acre (484 ha) New York State Wildlife Management Area (WMA) with a 4,500-foot (1,400 m) sandy beach on the eastern shore of Lake Ontario; it is in the Town of Richland in Oswego County, New York.

The sand that underlies the region was being mined for construction and industrial purposes, and led to concern about the long-term conservation of the area.

[7] Efforts by New York State to make conventional purchases of these properties for a WMA were unsuccessful, and in the end the land was obtained through a controversial use of eminent domain.

These experiments were apparently the foundation for the extensive beachgrass restoration that was subsequently undertaken along the entire length of the eastern Lake Ontario coastal dunes.

In 2007, Deer Creek Marsh WMA was designated as part of a New York Natural Heritage Area, the "Eastern Lake Ontario Barrier Beach and Wetland Complex".