Marshes

©Ducks Unlimited Canada/ Jeope Wolfe

Marshes are wetlands dominated by emergent, non-woody, plants. There are typically few, if any, trees or shrubs. Marshes can be freshwater or saltwater. Some marshes may hold water year-round, while others may only be flooded periodically. Drainage is slow, but the fluctuating water is nutrient-rich.

Habitat

Marshes are found around the world. Salt marshes can be found along coastlines and at the mouths of rivers that drain to the sea. Saltwater from the sea floods and drains with the tides. Cordgrass and glassworts are common plants. Freshwater marshes can be found along creeks, rivers, and lakes, as well as spread across the landscape in isolated locations. Water comes from the ground, precipitation, surface run-off, and adjacent waterbodies. Cattail, rushes, and reeds are common plants. The shallow water and plants in all marshes provide homes for a vast diversity of wildlife, from small invertebrates, to birds, reptiles, amphibians, mammals, and fish.

Conservation

Marshes face numerous threats, stemming from the past belief that wetlands of all types were wastelands and removing them was improving the land. Drainage for agriculture and urban development continue to be threats to marshes. However, new understanding about their abilities to hold water to reduce flooding, filter water, provide habitat, and store carbon, are helping to change policy and attitudes towards their protection.

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