Several of mine make that noise, and no one has gone broody yet. My Black Stars are the clackiest/most dino-sounding and they as a breed hardly ever go broody, so I personally think they are saying "Leave me alone, this is hard work!" My 8 year old recorded the clacking sound on her Nintendo DS and played it for my DH and he didn't believe it was a chicken making that noise until he actually went in the coop and witnessed it himself.