Only my SS does this. When she is in the nest box she wants to be left alone. If anyone or thing bothers her she fluffs herself up and makes this hissing cackling noise. Hubby refers to her as our velociraptor *lol* She reminds me of the lizards the have the collars around their necks that they unfurl in a defensive posture. The other hens don't make a peep is I happen to peer in while their on the nest box.