Principal Investigators: Tom F. Nalepa (NOAA/GLERL), and Edward Rutherford (CILER)

This research project is part of a monitoring program of benthic macroinvertebrate populations in Lake Michigan and Lake Huron. Changes in the abundance and composition of benthic populations provide a measure of environmental response to anthropogenic influences such as nutrient enrichment or invasive species. Specific objectives are thus to determine and assess changes in benthic populations over the long term. The original program in Lake Michigan was initiated in 1980 at 40 sites and samples have been collected at these same sites for two consecutive years every five years since. Samples to examine changes in the entire benthic community have been collected in spring, summer, and fall in 1980-1981, 1986-1987, 1992-1993, 1998-1999, and 2004-2005. Samples for just two taxa, Diporeia and Dreissena, have been collected every year since 1998. In addition, samples for these two taxa were collected in late summer at 160 sites over the entire lake in 1995, 2000, and 2005. In Lake Huron, samples for the entire benthic community were collected at 65 sites in 2000 and at 80 sites in 2003.