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 Aquatic EcosystemsWetland Drainage: Page 5 In the United States, early American colonists began draining wetlands in the 17th century, and various laws encouraging this activity were enacted through the years. Over half of wetlands of all types, and some 70 percent of riparian, or riverside, wetlands in this country, have been destroyed (Rezendes 1996). Losses continue under the Clean Water Act's weak regulations that place the US Army Corps of Engineers in charge of issuing permits to developers who apply for permission to fill in wetlands. The Corps' major role has been the construction of dams and levees, dredging of ports, and other water projects responsible for causing numerous extinctions among the nation's wildlife. These regulations exempt small and temporary wetlands, such as vernal pools and prairie potholes, and the Corps has been less than vigilant in enforcing wetland protection (Williams 1996). Federal legislation should change the authority designated to oversee wetlands conservation from the US Army Corps of Engineers to the Department of the Interior. The United States may be the only country in the world to allow its dike and canal makers to oversee conservation of these ecosystems. Wetlands protection should be far stricter in both federal and state legislation to prevent further losses.
Unfortunately, these important wetlands are often not protected by law in the United States, or, in the case of states such as Massachusetts, are protected only by some towns and only if officially registered as vernal pools (Appel 1999). These pools are being destroyed, often intentionally, by developers and homeowners who fear that building on or near the pool would be restricted (Appel 1999). Even when the pool itself is not destroyed, its water supply can be cut off by building nearby. A prime area for wood frogs in Framingham, Mass., disappeared, even though registered as a vernal pool, because the surrounding 25 acres of woodland were cut to construct a cinema complex (Ridout 2000). The required 125-foot buffer area of woods that was left surrounding the pool did not supply enough runoff water; the vernal pool dried out and the frogs disappeared (Ridout 2000). The disappearance of turtles from many areas in the East has been blamed on the filling of these important habitats where they migrate to lay their eggs.
Many swamp forests in the East and in the Midwest, as well as potholes essential as breeding habitat for waterfowl and stopovers for the continent's shore birds, were drained with government subsidies. Iowa lost 98 percent of its potholes; Minnesota, 75 percent; South Dakota, 35 percent; Montana, 27 percent and North Dakota, which had one-third of all these ecosystems, 49 percent (Williams 1996). The latter state's legislature discourages protection of the remaining potholes by requiring approval of conservation easements or purchase for conservation by an agricultural council (Williams 1996). This reflects the failure of federal and state governments to value wetlands for their ecological importance rather than for commercial purposes such as agriculture, construction or mining. In other parts of the world, similar attitudes prevail. The black-faced spoonbill (Platalea minor), a large white wading bird of Asia has been reduced to only about 700 birds (BI 2000). More than 200 of these birds winter in Taiwan's Chiku marsh, near the capital city, Tainan, now under great threat from development (WESPA 1994). A Taiwanese government official, when questioned about proposed drainage of the marsh, stated to CNN on January 6, 1994, "We can't stop our industrial progress for a few birds." Throughout the range of these endangered birds in east Asia's coastal wetlands, development has drained their habitats or converted them into aquaculture ponds (BI 2000).
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