I heard them way before I got to the swamp: they were squawking the way they do when a parent has brought food. Instead of feeding, the scene when I got there was more like a human telling his sibling what’s what.
You could practically hear “You’re not the boss of me!”
I’m not sure if this was backing down or just requisitioning.
And as is often the case with humans, it was all over a couple minutes later, apparently with no harm done.
A lone adult, perhaps from this nest, stood with a tired look at the edge of the pond. The adults all around the rookery are starting to look like they have had enough.