Midges and Mayflies: Assessing Stream Conditions Through Insect Communities

Project Summary

Trout streams contain more than fish and water. They are the milieu for hundreds of species, including insects, which reflect stream quality through their presence and abundance. In this study, researchers will partner with volunteers to collect and identify the empty larval cases of midges from 12 trout streams running into Lake Superior through Duluth. They will investigate whether species in the midge community show more sensitivity to subtle stream differences, particularly those associated with increased urbanization, than do the traditional species used to monitor stream health (mayflies, stoneflies, and caddisflies).

The researchers suspect that midges will be more sensitive indicators and also acceptable for use in projects monitored by volunteers. The researchers will also determine if there is a correlation between the stream insect community and the amount of impervious surface covering the stream watersheds. The information produced through this study will be made available online and translated into Spanish, Somali, and Hmong to reach minority audiences. The results will aid monitoring projects, especially those concerned with maintaining fishable streams.