I've been told that all the Collared Doves we have are the result of the white ones they release at weddings and football games. I see the white ones in pet stores sometimes.

After a few generations in the 'wild', they revert to what must be the original color phase. The biological niche they fill seems to compete with the Rock Doves (Courthouse Pigeons), and not with the native Mourning Doves...Geo