This is known as fluffing.
Often, dry chemical and dry powder types are hit on the bottom with a rubber mallet to make sure the powder is free-flowing, which is called fluffing the powder.
Similarly, it is also reported that the parent birds brooded by perching on the branch above the nest and fluffing their breast feathers out to cover it.
Live episodes are prone to mishaps and actors fluffing their lines.
When feather fluffing, they contract their muscles to raise their feathers to increase the air space next to their skin.
The male's courtship display involves fluffing out his breast feathers and running after the female; the species has no known aerial display.
An aggressive display involves fluffing up the feathers and holding the bill high.
A display of a male involved fluffing its feathers, holding the bill high and flicking wings while swaying from side to side.
