Basking Dragonflies

This photo was taken at Edmonton, Alberta, 5 June 1975, by Jim Erckmann. It shows Dennis Paulson stalking a very white quaking aspen trunk full of basking Leucorrhinia borealis and not realizing they were using his shirt as a similar basking spot. Note the smaller Leucorrhinia hudsonica in the midst of its larger relatives. Rather early in the morning, it was cool, but the low-angle sun was just the thing for these dragonflies, which had recently emerged and were virtually swarming in the area. I have rarely seen such a density of dragonflies.