Three images of the young Hoodies at two-to-three days old. The young ducklings after swimming around and foraging for food would often climb on a rock for a rest. They generally formed a small "HUDDLE", perhaps to stay warm or to discourage predators. I suspect it was to stay warm as every once-in-awhile one of the outer ducklings would jump on top of the pile to get to the centre, but then, maybe that's the safest place to be.
Top image: "Hey guys, you are pushing me off. Let me back up!"
"And back up he goes, but from the other side."
"Move over guys. I'm coming in."