Cockatiel shaking his head?

Question
Hi! I have a cinnamon cockatiel named Kiwi. Whenever I talk or sing to him, he shakes his head very quickly. Why does he do that? I've heard that the shaking can somehow be detrimental to a bird's health. Help? :(

Answer
You can relax, he won't shake his head off or hurt himself. It's actually pretty common.  These are adorable, smart little birds aren't they?  Is he new to you? Is there a certain pitch that he seems to respond to?  The shaking isn't up and down like he's going to regurgitate right? If it's this action, it should be discouraged if no other reason than he may give up his food (the act of regurgitation) and end up suffering a nutritional deficiency; otherwise, as long as it's just to certain sounds, there's probably no real need for concern.

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