My full grown Duck, Penguin, all of a sudden is doing this thing were he opens his beak and shakes his head around sometimes there is like a grinding noise I think from his beak? He isn't doing it constantly but every like 5-ten min I might see him do it. Other then that he is totally fine walking around and grooming himself he's breathing fine and quacking and all that he just stops here and there to do it and it looks like its anoying him he does walk over to the water dish and Drinks out of it but he continues to do it. Could he have something stuck in it? I don't want it choking him I'm really worried. He's perfectly healthy otherwise and he's a indoor duck he lives in my room with me so I don't think it could be like bugs or something. any advice?