Coastal Wetlands Getting Swamped
By Charlie Rhodes
While wetlands may conjure up images of “swamp things,” in reality these unique ecosystems have many vital and fascinating characteristics.
For example, wetlands provide crucial food and habitat for wildlife. Did you know that more than half of the fish caught for recreational or commercial purposes depend on wetlands at some point in their life cycles, as do 75 percent of our nation’s migratory birds?
Both saltwater (along the coastal shorelines) and freshwater (extending inland) wetlands occur in the coastal watersheds of the United States.
Wetland systems improve water quality and buffer coastal communities from erosion and flooding, while also providing recreational opportunities. A recent report Status and Trends of Wetlands in the Coastal Watershed of the Continuous United States 2004-2009 summarized the status and trends of coastal watersheds. Frankly, much of the report compiled by the U.S. Fish and Wildlife Service and the National Oceanic and Atmospheric Administration wasn’t good news.
During the study period, wetlands suffered a net national decline of 360,720 acres (an area about the size of Los Angeles), and an average of 25 percent increased loss compared to the previous five years. Our Atlantic Coasts saw a decline of 111,960 acres (larger than the city of Philadelphia). Losses and degradation of wetlands in coastal watersheds can be directly traced to population growth, changes in water flow, and increased pollution.
Some of the reported impacts include:
- The loss of an estimated that 7,360 acres of estuarine saltmarsh in the Atlantic coastal watersheds – mainly due to erosion and inundation from rising sea levels along shorelines near Delaware Bay.
- Forested freshwater wetlands declined by an estimated 405,740 acres. Of these losses, 69,700 acres (44%) were attributed to silviculture, the practice of harvesting trees in many swamps.
- Natural ponds declined by 16,400 acres (-3.9 percent), while detention or ornamental ponds increased by 55,700 acres (+19 percent). While this would appear to indicate a net gain, the tradeoff is that natural ponds, which often interact with other natural environments and provide additional benefits, were being lost while isolated decorative ponds or sumps of limited ecological value were being created.
While reestablishing and creating wetlands can offset losses, this study also found that these strategies have not been as effective in coastal wetlands as in other types. Challenges include costs, competing land use interests, and oversight limitations.
Wetland losses coupled with increasing frequency of extreme weather events like Hurricane Sandy make the mid-Atlantic coasts increasingly vulnerable to coastal flooding and inundation.
But not all of the news is bad. Many great opportunities still exist for citizens, industry, government agencies, and others to work together to slow the rate of wetland loss and improve the quality of our remaining wetlands. Learn more about what you can do to protect wetlands and about EPA’s wetland activities in the mid-Atlantic at the following: http://water.epa.gov/type/wetlands/protection.cfm; and http://www.epa.gov/reg3esd1/wetlands/ .
About the Author: Charlie Rhodes is a wetland ecologist who has been with EPA since 1979. He has worked nationally on wetlands in many capacities including impact assessment, delineation, and enforcement; and in many roles, including expert witness, instructor, and grant reviewer.
Editor's Note: The opinions expressed in Greenversations are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.