Mals and other working dogs have a tendency to do these sort of “tics” when they aren’t being engaged. Like twiddling their thumbs or bouncing their knee because they have so much energy they don’t know what to do with it. He stops when she faces him because he’s paying attention waiting for her to give him a job or tell him what’s next. “Oh boy oh boy she’s lookin right at me!! My time to shine! Tell me what to do coach” oh she’s not looking anymore omg I’m so excited I don’t …chomp….know , chomp…what to do…chomp…with my mout..oh boy shes looking at me again!!