I’m beginning to see patterns of behavior during pairing of Great Blue Herons. Here are some examples.
The Stretch
Usual flying configure when working - with the neck in the "S" configuration
During pairing, though, the male flies circles around the nest and his prospective girlfriend - with his neck extended.
Sometimes there is a lookout
Scratching his face
Passing a twig from male to female
Off to fetch another twig (nest building materials)
Returning with a twig
Passing the twig
Off for another twig
Fetching another twig - Neck in the "S" configuration
Returning with a twig
Off for more twigs
Returning with a twig
Landing
Passing the twig to the female (the construction supervisor)
Returning with another twig
Anxious female awaiting the twig
Female watching an intruder
Male returning with another twig
Off ro another twig
Time out for circular flying to impress the female (straight neck)
Straight neck for short circle around his girlfriend
Beak dueling