How old are they? the boys sing, but catch one, look at its vent, between the tail and the vent if there is a bulge and you sqeeze lightly and a white foam come out you have a boy, the more sexually active the bird is the bigger the bulge is. if the bird is young the bulge is small, might have to squeeze a little harder, most of the time you can see the bulge. if you have them on wire there will be little foam blobs in with the poop. the foam is 'pee'
It is not!! The 'pee' is the white part of the poop, not the foam! If the foam were pee, the females would have it too. It's like in any males 'stuff', there is sperm, then there is 'not sperm'. The 'not sperm' aids the sperm on it's travel....The foam is the 'not sperm' part of the quails' 'stuff'.