What are they?
Tidal wetlands are areas consistently covered by water during at least some tide stages. There are many different categories of tidal wetlands depending on the type of vegetation present and the amount of water during high and low tides.
Why are they important?
Tidal wetlands are some of the most important habitats on the Hudson River. They support several unique species that rely on the changing water level to survive, and are specially suited for that habitat type. Tidal wetlands are great places to spot abundant wildlife, including birds, fish, insects and plants. Juvenile fish often use tidal wetlands as nurseries because they can hide from predators in the shallow vegetated waters. Tidal wetlands are also important for humans because that can help reduce flooding by limiting wave action and acting as an intermediate habitat between the land and the water. They are often great places for recreation, and can be explored by kayak or canoe.
Where are they?
The Hudson River Research Reserve manages four main tidal wetlands where the public can visit, Iona Island, Piermont Marsh, Tivoli Bays and Stockport Flats, but there are many more tidal wetlands along the Hudson River. Maps of all of the tidal wetlands along the Hudson River estuary, developed from 2007 aerial photographs, are available on the GIS Clearinghouse.
How are they changing?
Since tidal wetlands are extremely dynamic systems, they are constantly changing. However, long term changes can be seen in vegetation type and sediment levels. Many wetlands have been invaded by the common reed, or Phragmites australis. Areas with native cattail tend to be much more biologically diverse than areas invaded by Phragmites, and more biodiversity in the plant community can increase the types of other animals that use a given area for shelter or food. As the climate changes and sea level rises, water levels may increase faster than wetlands can gain new sediment, which could cause decreased amounts of these crucial habitats for plants and animals.
How are we conserving them?
In addition to existing regulations that protect tidal wetlands from development and other threats, several individual sites are being actively managed to maintain native plant and animal communities. Control of the invasive plant common reed (Phragmites australis) in Tivoli Bays, Stockport Flats and Iona Island Marsh has been underway for several years. Herbicides that are approved for use in wetlands are carefully applied to kill the invasive plant, allowing native marsh plant communities to return.
