Aeshnids, like these blue-eyed darners (relatives of the equally lovely common green darner , are extremely specialized for nearly continuous flight, and spend hours at a time on the wing (go to this page for more pictures of males and females, and some in-flight images).   The blue males patrol territories around standing water, watching for the greenish females and for prey.   Occasionally they will hover in one spot and I was able to get images of several patrolling males in early October, at the San Jacinto Wildlife Area near Riverside, California (modern autofocus equipment can work wonders -- these males were hovering but nevertheless were in constant motion).  All dragonflies have amazing multifaceted eyes, but the sky-blue eyes of males of this species are more spectacular than most (as emphasized in the views here).
            (Another binomial for this species is Aeshna multicolor.)