This dragonfly has quite a descriptive name, having four spots on each pair of wings (although that seems to add up to eight). They can be found in June and July basking on a leaf like the one in the photograph, or flying up and down over the water. They can be quite territorial, aggressively chasing off other dragonflies. This one was in the reed bed at the southwest end of the main lake, but they can be found all along the river.

There is a form of Four-spotted Chaser called Praenubila which has larger, more smudged spots. The one below was found along the river walk.