The national lakeshore's many terrestrial and aquatic environments offer great habitat where creeping, crawling and buzzing creatures can live and breed. Insects (along with their arthropod relatives the spiders, millipedes, mites and tiny aquatic zooplankton) make up the bulk of the park's animal life.
Most visitors tend to notice insects only when swatting biting flies and mosquitoes, but beautiful insects abound as well. Keep an eye out for the many colorful butterflies, dragonflies and damselflies found in this region. Carefully turn over a rotting log to see the array of fascinating small creatures usually hidden from view – but make sure to carefully replace the log again!
The important role of insects is clear to scientists. Bees, flies, and other insects function as pollinators; scavengers like beetles break down dead plant and animal matter. High numbers of many species such as mosquitoes provide food for bats and other hungry creatures. Insect monitoring at the lakeshore has primarily focused on aquatic insects and larvae as they are good indicators of water quality. The presence of mayfly, stonefly and caddisfly larvae in the lakeshore's cold fast-flowing streams indicate that these waters are in good ecological health.
Pictured Rocks is one of several parks involved in a regional NPS study to detect the presence of mercury in aquatic environments by sampling dragonfly larvae. Information from this study will help scientists understand how mercury in northern lakes spreads throughout the aquatic food web.