Threatened palustrine wetland habitats

The situation for palustrine vegetated wetlands is that they continue to be destroyed at alarming rates. Palustrine forested wetlands have been subjected to many changes, including conversion to farmland and filling for development and roads.

Palustrine wetlands are wet or marshy habitats. They include all non-tidal wetlands dominated by trees, shrubs, persistent emergents, emergent mosses, or lichens, and all such wetlands that occur in tidal areas where salinity due to ocean derived salts is below 0.5 percent.

The Everglades is a freshwater wetland of marshes, wet prairies, swamps, and tree islands. Described as a "River of Grass", it once flowed in a 65x170 km basin from the southern shore of Lake Okeechobee to the mangroves on Florida's southwestern coast. Rainfall, formerly the main nutrient source, provided a slow, continuous sheetflow through the basin into Florida Bay, feeding North America's only living coral reef and a tremendous diversity of marine life.20 Since the turn of the century, 65 percent of this wetland has been drained; the sheetflow has been channelized and diverted; water quantity and quality have drastically decreased; and severe ecological deterioration has occurred.

In the Chesabeake watershed USA, between 1982 and 1989, palustrine vegetated wetlands (freshwater marshes, wet meadows, swamps, and bogs) declined by 2%. A total of 14,580 hectares was converted to drylands and water bodies: 5,954 hectares of forested wetlands, about 4,293 hectares of emergent wetlands, and about 4,334 hectares of scrub-shrub wetlands. These collective losses equal an area about the size of the District of Columbia. In addition, about 7,290 hectares of palustrine forests were harvested for timber. This is not considered a loss, however, since these areas are still wetlands that in time will revert to forested wetlands. Virginia had the greatest palustrine vegetated wetland losses of any state in the watershed, losing approximately 9,315 total hectares: Maryland lost about 2,025 total hectares of the palustrine vegetated wetlands during this time and more than 1,013 hectares of palustrine forests. Pennsylvania lost almost 1,600 total hectares. Despite the existence of federal regulations, nontidal freshwater wetlands continued to experience heavy losses in the USA from 1982 to 1989, destroyed through conversion to drylands and to open waters such as reservoirs and ponds. Seven areas were identified as hot spots where tremendous losses of certain wetland types occurred from 1982 to 1989: southeastern Virginia, the Piedmont region of Virginia, the Eastern Shore of Maryland, western Delaware, the upper Coastal Plain of Virginia, western Virginia (Blue Ridge and Appalachians), and northeastern Pennsylvania (Susquehanna, Bradford, and Tioga counties). These areas accounted for about 85% of the palustrine vegetated wetlands that were converted to drylands and open waters in the USA during the 7-year study period.