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Keeping an Eye on Wetlands

EPA researchers develop ways to study, assess, and report on the state of the nation's wetlands.


Two EPA researchers collecting wetlands samples

EPA wetland researchers Mary Kentula, Ph.D. and Teresa Magee collect vegetation samples in a wetland outside Corvallis, Oregon.

If you appreciate ducks and other waterfowl, fish, seafood, and natural flood control and water filtration, you are already a fan of wetlands. Defined by ecologists as those habitats where the degree of water saturation largely determines the make-up of the species living in the ecosystem and the types of soil found, wetlands provide many ecological, economic, and social benefits.

A few centuries ago, the continental United States had more than 220 million acres of wetlands. Today, less than half remain.

Reducing the loss of wetlands is one of EPA's goals in meeting its mission to protect human health and the environment. To that end, Agency scientists and their partners provide the critical data, analysis, and assessments used to monitor the status and trends of the Nation's wetlands.

EPA provides the scientific foundation for the reports and publications that wetlands managers and other decision makers rely on to better protect wetland resources.

EPA's Report on the Environment

Report on the Environment
The Report on the Environment (ROE) presents a collection of more than 80 environmental indicators useful for understanding general trends in the condition of water, as well as air, land, human health and exposure, and ecological condition.
The Report's water chapter covers a range of regional and national water issues, including providing key information on Wetland Extent, Change and Sources of Change.

National Coastal Condition Report IV

National Coastal Condition Report IV

Released by EPA, The National Coastal Condition Report, describes the ecological and environmental conditions in U.S. coastal waters, including coastal wetlands. The report summarizes the condition of ecological resources in the Nation's coastal waters and highlights several exemplary federal, state, tribal, and local programs that assess coastal ecological and water quality conditions.

Status and Trends of Wetlands in the Conterminous United States

Status and Trends of Wetlands in the Conterminous United States

The report represents the most comprehensive and contemporary effort to track wetlands resources at a national scale. When paired with EPA's National Wetland Condition Assessment (see below), "Status and Trends" will provide the public and government agencies with comparable, national information on wetland quantity and quality.

EPA scientists have been working since 2007 to advance the science behind wetland assessments through the National Wetland Condition Assessment (NWCA), which, when complete, will provide a comprehensive statistical survey of the quality of the Nation's wetlands.

"This is the first time a network of partners has been brought together to develop standardized, uniform assessment techniques that will lead to statistically-valid estimates of the ecological condition of wetlands on a national level," says EPA ecologist and wetlands expert Mary Kentula, Ph.D.

In the first phase, Kentula and her EPA colleagues worked to develop those techniques with partners from other federal agencies (including the U.S. Fish and Wildlife Service, USDA National Resource Conservation Service, National Park Service, U.S. Forest Service and NOAA's National Estuarine Research Reserve Program), states, Tribes, and others. The process was also designed to foster collaboration and help implement wetland monitoring programs that would benefit all the partners and support local decision makers.

That work was put into practice this past summer, when 55 field crews surveyed some 1,250 wetland sites across the contiguous U.S. and Alaska. The 33,000 or so samples the field crews collected are now being analyzed by different labs across the country, with completion expected in fall 2012.

Following peer review and a public comment period, EPA is scheduled to release a final wetlands assessment in December 2013.

When complete, NWCA will present a significant advancement in the understanding of wetland quality nationwide, providing resource managers and decision makers with critical information they need to better protect the function and integrity of the nation's wetlands for current and future generations.

Ultimately, the impact of that work will be evident by the presence of waterfowl, fish, seafood, natural flood control and water filtration, and other benefits of the nation's wetlands.

Learn More

EPA Wetlands Research

The National Wetland Plant List Exit EPA Disclaimer

EPA Science Notebook: Wetlands

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