88 
Rose, Everton, Stankavich, and Walke 
Slightly elevated “mesic islands” supported oaks and even beeches, trees 
that are typical of the upland habitats in the region. Thus, the Dismal 
Swamp that developed after the recession of the Wisconsin glacier from 
the region 8-10 thousand years ago was a swampland of vegetational 
diversity, a diversity maintained by a regime of flood and fire. 
The flooding cycle is in part a result of the unusual geology of the 
swamp, which includes an escarpment on the western boundary and 
underlying impervious clays that prevent the rapid loss of rainfall to an 
underground aquifer. Thus, water moves slowly eastward toward the 
old duneline that forms the eastern boundary. In the winter months, 
reduced evapotranspiration and moderate rainfall combine with a high 
water table to inundate many sections of the swamp. 
Since the Colonial Period, many land developers have attempted to 
exploit the swamp. Even George Washington participated in a scheme 
to drain and clear the swamp and convert it to farmland. Invariably 
those efforts failed, and always the swamp returned to forested swamp- 
land. However, the lowered water table resulting from the construction 
of ditches and the suppression of fires in this century has changed the 
character of the forest. Today, the Dismal Swamp forests are pre- 
dominantly black gum, Nyssa sylvatica , water gum, Nyssa aquatica, and 
red maple, Acer rubrum, with scattered patches of bald cypress and 
Atlantic white cedar. The formerly extensive areas of cane and evergreen 
shrub thicket have been greatly reduced (Musselman et al. 1977). Stands 
of cane now are virtually absent except where preserved or maintained 
by human activity, such as the 3- to 5-year mowing treatment under a 
powerline. As a result, the swamp is moving slowly and inexorably in 
the direction of domination by maple and gum trees, and towards less 
vegetational diversity. We must assume that this will not favor the 
biota, including the mammals, which has become adapted to life in a 
physically harsh and biologically variable environment. In an effort to 
conserve this distinctive swamp forest, the Union Camp Corporation 
donated nearly 19,000 ha of land within the Great Dismal Swamp to the 
Nature Conservancy in 1973, which in turn deeded the land to the U.S. 
Fish and Wildlife Service (USFWS). In 1974, the USFWS created the 
Great Dismal Swamp National Wildlife Refuge, which has grown 
through other donations and purchases to its present size of more than 
45,000 ha, about three-fourths of which is located in Virginia. 
In their efforts to attract buyers, early land developers often greatly 
exaggerated the numbers and kinds of wildlife in their descriptions of 
the swamp (Handley 1979). The first accounts of what actually was 
present were written in a U.S. Geological Survey annual report (Shaler 
1890). Shortly afterwards, a major collecting effort was made by the 
