Like clean water, wildlife, seafood? Then you'll love wetlands
Bay Naturalist / By Kathy Reshetiloff - Bay Journal
Diversity is the spice of life. And contrast, in all forms, makes life more interesting. Nowhere is this more apparent than where land and water meet. Whether it’s salt marshes, mountain bogs or wooded swamps, the blending of both terrestrial and aquatic environments creates a wetland, an ecosystem that often supports more life than either the land or water alone.Wetlands are semi-aquatic lands, flooded or saturated by water for varying periods of time during the growing season.
Because of the presence of water, wetlands are characterized by a predominance of hydrophytes (plants adapted to wet soils) and the presence of hydric soils (periodically saturated or flooded soils). Wetlands include bogs, swamps and marshes and shallow water areas of rivers, lakes and ponds. Two major groups of wetlands are found in the Bay watershed: estuarine and palustrine.
Estuarine wetlands are tidally flooded and range in salinity from fresh to salt water. Estuarine wetlands are the marshes found mainly along the shore of the Chesapeake Bay and tidal portions of rivers.
Palustrine wetlands are freshwater bogs, marshes and swamps bordering streams and rivers, filling isolated depressions and fringing lakes and ponds.
In the past, wetlands were regarded as wastelands, conjuring up images of dark, dangerous places filled with mosquitoes, biting insects and poisonous snakes. Because of these negative images, people filled or drained wetlands. In rural areas, wetlands were often put into crop production, and in urban areas, wetlands were converted into housing developments, shopping malls and industrial plants.
This misguided notion led to a rapid destruction of wetlands over the last 250 years. During colonial times, it has been estimated that more than 200 million acres of wetlands covered the country. Today, less than half of those wetlands remain and more continue to be lost.
The majority of wetland loss is due to draining and filling for agriculture, housing, highways and commercial buildings. Between the 1950s and 1970s, the United States lost nearly 460,000 acres per year, including more than 2,800 acres lost annually in the Chesapeake region.
Our understanding and appreciation of wetlands has since grown. Ecologically, wetlands are extremely valuable and productive areas. Many of the Bay’s living resources depend on wetlands to survive.
Water levels in wetlands vary from nearly dry to completely flooded over the course of a year. These shifts in water levels allow some types of wetlands to function as two different ecosystems, account- ing for the large numbers of animals that depend on them. For example, when a forested swamp floods, fish like bass and herring move in to feed and spawn. Fish and crayfish, in turn, provide food for mink, otters and raccoons. When the swamp becomes drier, the fish stay in the stream channels and mammals and birds move throughout the forest.
Wetlands are hot spots of biological diversity. About 43 percent of the nation’s endangered species depend on them for survival. One third of all North American bird species depend on wetlands for food, shelter or breeding habitat. Coastal wetlands provide critical habitat for shorebirds, migrating waterfowl and fish. Thousands of smaller animals, including aquatic insects, snails, mussels and tiny crustaceans thrive in wetland communities.
Wetlands are important for more than just wildlife. Do you like seafood? Roughly two-thirds of commercially valuable fish and most shellfish use tidal wetlands as spawning and nursery areas. Do you like crabs? Wetlands provide food and cover for blue crabs as well as helping to filter out sediment that would otherwise cover Bay grasses, critical to crabs as spawning and nursery areas.
Do you want to protect your home and property from flooding? Controlling flood and stormwater is an important function of wetlands. Fast-moving flood waters are slowed by the vegetation and temporarily stored in wetlands. The gradual release of this water reduces erosion and property damage. Coastal wetlands also absorb the impact of storm surges, stabilizing coastlines during major storm events.
What about clean water? Upland runoff water is cleansed as it passes through wetlands, which act as natural filters, trapping sediment and capturing nutrients, such as nitrogen and phosphorus. Excess sediment can bury fish eggs and bottom-dwelling organisms and prevent light from reaching Bay grasses. Excessive nutrients trigger algae blooms that, as they decompose, rob water of life-sustaining oxygen.
Wetlands also play a crucial role in recharging groundwater supplies. Not only do they assure an abundant supply of fresh water for irrigation and drinking, they also help to create groundwater pressure, which keeps saltwater out of coastal aquifers. As municipal and agricultural demands for water increase, the importance of wetlands in maintaining water supplies grows.
Do you spend your free time outdoors? The wetlands of the Chesapeake region offer boating, fishing, waterfowl hunting, and wildlife watching. Outdoor recreation is big business. In 1996, Americans spent $101 billion on wildlife-related activities including hunting, fishing and wildlife watching. Many of these activities occur in wetlands.
Protecting our remaining wetlands is an essential step in holding the line for environmental quality. Further wetland destruction or degradation can ruin the fragile Chesapeake ecosystem and eliminate a way of life that you now enjoy.
So what can you do? If you have wetlands on your property, keep them. They improve water quality, reduce flood and storm damage, provide habitat for fish and wildlife and support recreational activities. Restore lost wetlands. Many state and federal natural resource agencies and private conservation groups have programs to help landowners re-establish wetlands.
Buy Federal Duck Stamps, which are available at post offices and National Wildlife Refuges. More than 5 million acres of wetlands and other migratory bird habitat has been purchased with funds from the sale of the stamps. Federal Duck Stamps can also be purchased directly from the Federal Duck Stamp office by calling toll-free 1-888-534-0400.
See a wetland. Visit National Wildlife Refuges or local wild lands to learn more about wetlands and the wildlife they support. Teach your children the importance of wetlands and other wild lands. Get involved with local issues that may affect wetlands in your community. Wetlands are often lost in small parcels, but the cumulative effect is devastating.
Kathryn Reshetiloff is with the U.S. Fish and Wildlife Service’s Chesapeake Bay Field Office in Annapolis.
Like clean water, wildlife, seafood? Then you'll love wetlands
Article from Bay Journal - March 1999
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