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Tidal Wetlands

Tidal Wetlands at Flax Pond in Old Field, NY
Tidal Wetlands at Flax Pond in Old Field, NY

A typical tidal wetland is the salt marsh which is found in the near shore areas all around Long Island, the lower Hudson River, and along the entire Atlantic coast of the United States. These areas are dominated by grasses and other marsh plants which are adapted to the rise and fall of the tide and the salty water it brings. The blades of marsh grass provide a hiding place for many juvenile fish and habitat for many other animals as well. The grass blades become a vital part of the food chain when they break off and decay, providing food for detritivores (animals that eat decaying organic material) and nutrients to the marine environment. Tidal wetlands in New York State are found on the Hudson River from the Troy Dam south to the southern tip of Staten Island, and along the entire shoreline of Long Island, including the shorelines of Gardiners Island, Shelter Island and Fishers Island.

The statutory definition of a tidal wetland can be found in New York's Environmental Conservation Law, Article 25, entitled "Tidal Wetlands" (link leaves DEC's website).

tidal wetland map

Habitat Protection - Tidal Wetland Act

New York State recognized the importance of this unique habitat and sought to insure its protection from filling and dredging, human activities that have drastically reduced the amount of tidal wetlands in New York, by passing the Tidal Wetland Act in 1973. In 1974, DEC collected a set of aerial infrared photographs of all the tidal wetlands on Long Island and along the lower Hudson River. Using these photographs, DEC established the New York State Official Tidal Wetlands Inventory, a set of maps delineating and classifying all the tidal wetlands in New York.

These maps are used by DEC and other municipal agencies to control and manage the development, filling and dredging of areas in and around New York's valuable tidal wetlands. This Inventory is also available to the general public to examine (see links in the right column). The New York State Official Tidal Wetlands Inventory is maintained by DEC's Division of Marine Resources in the Bureau of Marine Habitat. Many individuals consult these maps before undertaking any building or landscaping along the shoreline.


Under the Tidal Wetlands Act, DEC administers the Tidal Wetlands Permit Program, which regulates activities in tidal wetlands and their adjacent areas.

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