Wetlands

Wetlands are transitional areas between land and water. While some wetlands are noticeably wet, others do not always have visible water. An area is defined as a wetland based on its soils and vegetation.

• All wetlands are dominated by hydrophytes, which are plants that are adapted for life in wet soils.
• Wetlands also have hydric soils, which are soils that are periodically saturated or flooded.

What Types of Wetlands Are Found in the Chesapeake Bay Watershed?

There are two broad categories of wetlands found in the Chesapeake Bay watershed:

• Tidal, or estuarine, wetlands are flooded with salt or brackish water when tides rise. Tidal wetlands are found along the shores of the Bay and the tidal portions of streams, creeks and rivers.
• Non-tidal, or palustrine, wetlands contain fresh water. Eighty-six percent of the wetlands in the Chesapeake Bay watershed are non-tidal. Palustrine wetlands are located:
  • On floodplains bordering streams and rivers.
  • Fringing the shorelines of lakes and ponds.
  • Filling isolated depressions.
  • Covering broad, flat areas at or near sea level where water may collect (such as many areas on the Delmarva Peninsula).

Wetlands are further distinguished by their vegetation.

• Emergent wetlands are made up of grasses, sedges and other leafy, non-woody plants. They are often called marshes or wet meadows.
• Shrub wetlands are characterized by low- to medium-height woody plants. These are often called bogs or shrub swamps.
• Forested wetlands are dominated by trees. These include wooded swamps and low-lying hardwood forests near rivers. Sixty-eight percent of the wetlands in the Chesapeake Bay watershed are forested.

How Are Wetlands Important?

Wetlands provide critical habitat for hundreds of species of fish, birds, mammals and invertebrates. They also improve the health of the Bay and protect shorelines and property, as well as provide opportunities for outdoor activities.

Wetlands Improve and Protect the Chesapeake Bay's Health

Situated between the land and the water, wetlands act as buffers by slowing the flow of pollutants into the Bay and its tributaries. As polluted stormwater runs off the land and passes through wetlands, the trees and grasses in wetlands filter and absorb nutrients, suspended sediments and chemical contaminants before these pollutants can flow to nearby waterways.

Wetlands also help control erosion. Just like a sponge, wetlands soak up and hold large amounts of flood water and stormwater runoff, gradually releasing the water over time. Wetlands along the edges of streams, creeks, rivers and the Bay stabilize shorelines and protect properties from floods and wave action.

Wetlands are especially important in our cities, towns and suburbs, where development and impervious surfaces increase the rate and volume of polluted stormwater runoff.

Wetlands Provide Important Wildlife Habitat

Countless wildlife species that live in the Chesapeake Bay watershed depend on wetlands for their survival.

• Tidal wetlands are a winter home for waterfowl that visit the Chesapeake Bay as they migrate along the Atlantic Flyway.
• Muskrats, wading birds and other widlife rely on wetlands for food and cover.
• Many commercially valuable species of fish and shellfish use wetlands as spawning or nursery areas.
• Thousands of aquatic species, including worms, snails, insects, mussels, tiny crustaceans and reptiles and amphibians, thrive in wetlands. In turn, larger animals depend on these small aquatic species for food.

Wetlands Are Valuable Economically and for Outdoor Activities

Wetlands are economically valuable because they provide opportunities for fishing, crabbing and hunting. Since they are habitat for commercially important fish and shellfish, wetlands are vital to the health of the Chesapeake Bay's commercial fishing industries.

Additionally, many people visit wetlands for popular hobbies and family activities such as boating, bird watching, photography and wildlife study.