The information I was able to obtain when I was looking into Quakers advised that this is why they are commonly known as Quakers, because of the "quaking" that they do. It is something that the bird does when it is young and grows out of for the most part. It should likely go away at the 6-9 week mark, but some go longer than that. How old is he?
That said, I tend to agree with zazanomore, if you are concerned about it, it may be worth a vet visit, if for nothing else than to calm your nerves and get him checked over. Let us know what happens.





