Mr. Dunn at Grand Junction Tn. is convinced the turkeys got them....it couldn't be true because the quail were gone before there were very many turkeys.
I think it's a combination of things topped off with farming chemicals...a guy I was talking to the other day thinks it was caused by arial spraying.

One thing I do know is Ft.Campbell Military base has lots of wild turkeys and lots of wild quail.
With a little scientific investigation at the base an answer might be found.