We see a lot of herons around here - seldom a day goes by that I don't see one or two along the shore, and at low tide I may see up to a dozen. Though they form large colonies with many nests in high trees at breeding time in spring, for the rest of the year they are primarily loners. Solitary foragers, they may share a feeding spot but only by maintaining their distance from one another.
I usually see them in one of two positions - either standing completely still, upright, like a guard at Buckingham Palace .....
...or slowly wading through the water is a semi-crouched position, the neck shaped like an "S" as they search for food:
Often they will choose a post or a rock or even a liferaft to provide a higher vantage point from which to see dinner in the waters below:
So it surprised me on my beach walks last week to see two herons with their beaks up in the air, one following the other. He was like a stalker, following the other across the bay, starting from at least a couple of hundred feet away, and rapidly closing the distance.
As breeding season is long past, I was even more baffled when they suddenly both opened their wings and began rotating counter-clockwise, completing several rotations, like some heron version of synchronized swimming, or perhaps a heron rendition of Swan Lake:
As suddenly as it started, it stopped, and they headed back again, this time the stalker becoming the stalkee.
Eventually, one flew away further down the beach and both began feeding in mannerly fashion, each maintaining a suitable distance from the other.
When I got back home, I did a little research to find out if herons ever breed in summer, and to learn what their mating rituals are. Instead, I learned that the display I had witnessed was a behaviour used to defend one's feeding territory. According to All About Birds,
Away from the colony, Great Blue Herons defend feeding territories from other herons with dramatic displays in which the birds approach intruders with their head thrown back, wings outstretched, and bill pointing skyward. (Source)
I guess the duel between these two was a draw, as on our evening walk that same day, I saw them almost side by side standing on the berm that leads to the old wharf. They hung around as a pair until the long weekend, when presumably they (like me) decided there were just too many people around and they took off for quieter places. I felt privileged, however, to have observed their little ritual on one of my early morning low tide walks.