Odonata as indicators of pollution, habitat quality, and landscape disturbance

The Odonata have well resolved taxonomy, conspicuous diurnal adults, contact with aquatic and terrestrial environments, and a broad range of environmental sensitivity across species, making them a valuable group for environmental appraisals. Odonate nymphs are commonly tested in aquatic ecotoxicological and bioaccumulation studies and often applied with other aquatic macroinvertebrate taxa in pollution-based biotic indices. Some of the more recent work aims to explain the evolutionary context of contamination risk and to increase mechanistic understanding of contaminant effects. Adults or exuviae are typically featured in habitat quality assessments with tools such as the Dragonfly Biotic Index, regional lotic quality indices, and coarse taxonomic metrics that will be especially useful in regions lacking descriptions and keys. Adults are further being used in landscape disturbance assessments where removal of non-breeding occurrences can reduce noise and strengthen signal. The future may move toward macro-ecological health assessments enabled by extensive citizen science and vulnerability trait data.