TRENDS

Unfortunately, the benefits wetlands provide to society and to individual landowners are neither widely understood nor appreciated. From the 1780's to the 1980's it is estimated that the 20 state Northeastern Area, an administrative unit of the U.S.D.A. Forest Service, lost 59 percent of its wetlands (Dahl 1990). To understand the forces of change, consider the Chesapeake Bay watershed, which comprises portions of the states of Delaware, Maryland, New York, Pennsylvania, Virginia and West Virginia. The Chesapeake Bay watershed has lost nine percent of its noncoastal marshes and six percent of its inland vegetated wetlands between the mid-1950's and the late 1970's (Tiner 1987). Forested wetland losses during this period were greatest for the state of Virginia which lost nine percent of its forested wetlands during a 21 year period (Tiner 1987). It should be noted for the purposes of data interpretation that Virginia is included in the Chesapeake Bay data, but is not included in the data for the Northeastern Area.		Wetland Losses in the Northeastern Area thousands of acres State Estimated Wetland Circa 1780 National Wetlands Inventory 1980 Percent Change Connecticut 670 173 -74 Delaware 480 223 -54 Illinois 8,212 1,255 -85 Indiana 5,600 751 -87 Iowa 4,000 422 -89 Maine 6,460 5,199 -19 Maryland 1,650 440 -73 Massachusetts 818 588 28 Michigan 11,200 5,583 -50 Minnesota 15,070 8,700 42 Missouri 4,844 643 -87 New Hampshire 220 200 -9 New Jersey 1,500 916 -39 New York 2,562 1,025 -60 Ohio 5,000 483 -90 Pennsylvania 1,127 499 -56 Rhode Island 103 65 -37 Vermont 341 220 -35 West Virginia 134 102 24 Wisconsin 9,800 5,331 -46 TOTAL 79,791 32,818 -59 Currently, about twelve percent of the wetlands in the Chesapeake Bay watershed are classified as estuarine or coastal wetlands ( Tiner 1994). Coastal wetland losses continue to result from conversion to estuarine waters by rising sea levels, coastal erosion and dredging. Losses of coastal wetlands to agriculture have increased significantly since 1982.

After Tiner 1994	After Tiner 1994
The remaining eighty?eight percent of wetlands in the Chesapeake Bay watershed are various types of inland wetlands. Sixty percent of the total wetlands in the Chesapeake Bay watershed are inland wetlands classified as palustrine forested wetlands. Actually, forested wetlands progress from forested wetlands to emergent wetlands to shrub?scrub wetlands and back to forested wetlands creating a sort of dynamic equilibrium as individual forests progress through the various plant successional stages in response to management activities or natural phenomena. Palustrine shrub?scrub wetlands and palustrine emergent wetlands make up ten and eleven percent of the total wetlands respectively. Consequently, appropriate forest management activities have the potential to favorably effect more than sixty percent of the total wetlands
After Tiner 1994	After Tiner 1994
After Tiner 1994	After Tiner 1994
in the Chesapeake Bay watershed. Current data indicates the primary threat to forested wetlands is conversion to ponds and reservoirs; a secondary threat is conversion to agriculture. The threat of conversion, both to agriculture and to lakes and ponds, has increased significantly for palustrine shrub?scrub and palu?strine emergent wetlands. While figures impart a sense of the magnitude of what we have lost, they do not tell the entire story. Pollution, changes in the amount of water entering a wetland, drainage, urban development and other activities which may not necessarily occur in wetlands, often cause impacts to wet lands and result in severe degradation and impairment of function. Many of these impacts cause changes that are difficult to detect until related effects become apparent. At that point, only significant contributions of time and resources can repair the damage. Wetlands are extremely fragile and, in many cases, the damage may be irreversible. Inland forested wetlands comprise the largest segment, almost 50 percent, of the remaining wetlands in the lower 48 states (Tiner 1987). Management strategies adopted for these wetlands could have a significant impact on the benefits these wetlands provide to society in the future.
After Tiner 1994	After Tiner 1994

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