Biological and Chemical Monitoring of Two Newly Created Wetlands in Central Wisconsin

Abstract

The United States Army Corp of Engineers, the agency responsible for issuing dredge and fill permits in the U.S., allowed Consolidated Papers Inc., of Wisconsin Rapids, Wisconsin, to create and enhance wetlands on the Fontaine Mitigation Site (FMS) (9.5 ha) and the Nash Road Mitigation Site (NRMS) (14.6 ha) to mitigate for other wetland losses. I monitored these sites from February 1993 to August 1994 to evaluate changes in aquatic and terrestrial vegetation, aquatic invertebrates, wildlife use, water chemistry, and the hydroperiod fluctuations. During this 18 month period, 70 and 121 species of terrestrial plants, 42 and 32 aquatic invertebrate families, and 31 and 37 songbird species were identified on the FMS and NRMS, respectively. In addition, 21 species of aquatic plants and 3 small mammal species were identified on each site. Five amphibian species were identified on the NRMS. Hydroperiod, water chemistry and fluctuations of surface and groundwater were also monitored during this period. Fluctuations in water level were determined with staff gauges and groundwater monitoring wells. Directional flow of water through the FMS was from northwest to south east and at the NRMS it was from south to north. Water chemistry results at the FMS indicated the smaller perimeter ponds were more influenced by precipitation, as opposed to the large pond which was more influenced by groundwater. Elevational rise and fall of water levels supported this conclusion. Biologically and chemically, each site functioned as designed. At the FMS, the perimeter ponds acted as nutrient traps and improved the quality of water passing through the system. Species richness of terrestrial vegetation steadily declined since 1991 at the FMS and since 1992 at the NRMS.