How does algal biomass and species composition in caddisfly nets differ from adjacent rocky substrate?

Abstract

This study attempts to characterize differences in algal biomass and species composition in caddisfly nets relative to their adjacent rocky substrate. To test this, we compared algae species present in caddisfly nets versus substrates and characterized differences in biomass by comparing chlorophyll a content in each sample. Results showed a significantly higher biomass in net relative to rock samples and a high degree of overlap between algae species in net and rock samples. This suggests that net-spinning caddisflies act as a non-selective trap for particulate matter in the drift and have little effect on the abiotic variables directly affecting algae composition.