Macrohabitat distribution of caddisflies (Trichoptera) in a northern Michigan stream.

Abstract

This study investigates the relationship between current velocity and the density and distribution of caddisfly larvae of different families. Caddisflies are important benthic organisms in stream ecosystems. They can be restricted to certain environments by such factors as availbility of dissolved oxygen, pollution levels, competition and predation. A northern Michigan stream was sampled to calculate the density of caddisflies in macrohabitats of different current velocities. I found that larvae of Hydroptilidae and Glossosomatidae varied significantly among macrohabitats, while those of Limnephilidae, Brachycentridaae, and Hydropsychidae did not.