Zusammenfassung: | Aquatic insects were sampled monthly from Elk Creek in northwestern Pennsylvania, from both coarse woody debris (CWD) and benthic habitats, to determine the density and species composition of insects colonizing both habitat types. Degree of conditioning of CWD was evaluated to determine if insects preferred to colonize wood in a particular state of decay. One-way ANOVA revealed that mean overall density of aquatic insects was significantly greater (F = 102.34, p < .001) in cobble benthic habitats (1235/m2) than on CWD (448/m2). Stage of decay was a significant (F = 94.67, p < .001) factor in colonization of CWD by insects. The greatest mean annual densities of insects were collected from CWD in decay stages III (905/m2) and V (826/m2), which did not differ significantly from one another. Overall, this study shows that CWD is an important habitat in Elk Creek and that wood condition is a significant factor in colonization.
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