Like male White Tails, the males defend their lakeside territories by flashing their blue-white tails at each other, and when that fails they chase each other around. Females spend less time around lakes. They can be seen laying their eggs by flying just above the surface of the water and repeatedly dipping their abdomens down into it.
Juveniles are easy to identify, with their beautiful patterns of black, yellow and golden brown.
Adult males have the same pale blue color as Eastern Pondhawks, but can be distinguished by their green eyes, the stripes on the sides of their thoraxes, and dark tips of their abdomens. Adult females develop blue color like the males, but more slowly. In the Twin Cities area, I've seen them at Baker, Carver, and Hyland Park Reserves. They are also common in Itasca State Park. Four-Spotted Skimmer up to Dragonflies and Damselflies Up close with a male Blue Dasher.