Macroinvertebrate Photo Gallery

Macroinvertebrates are animals without a backbone that can be seen with the naked eye. These bottom-dwelling animals include crustaceans and worms but most are aquatic insects. Beetles, caddisflies, stoneflies, mayflies, hellgrammites, dragonflies, true flies, and some moths are among the groups of insects represented in streams. Macroinvertebrates are an important link in the food web between the producers (leaves, algae) and higher consumers such as fish.

Need to identify an aquatic macroinvertebrate you found in a stream? Use our dichotomous key.

Visit the Stroud Center’s Leaf Pack Network® website to learn about a simple experiment that uses tree leaves and aquatic insects to determine the health of your local stream.

Click on images to enlarge. All photos by David H. Funk.