Both cluck when they are excited to see humans approach the pasture. It’s loud and obvious, meaning an alpaca has seen or heard or smelled something scary: a wolf, or a shadow, or … Alarm Call – I had never heard this until Zula arrived. If Zula sees something she fears, she will signal the herd of the threat by using her alarm … I mentioned earlier that Avalon clucks and Stormy does too. Another unambiguous one: the alarm call. Clucking – An alpaca will also cluck to express concern or to signal friendly behavior. Ariana and Princess both clucked for their young crias. This is a sort of donkey-like “hee-haw,” but higher pitched and less rusty-sounding than a donkey’s.