I'll weigh in. I think in areas with vast habitat, favorable weather, low predator count, both human and natural, are of no signifigance. For quail, we now know this is 3000-5000 acres and a population of at least 800 birds. A Missouri Dept.of Conservation study revealed with quail, birds taken from the population, late in the season, January on, reduces the breeding population in the spring, by that number. Something about late season birds being survivors, the hardest period being January through mid-March. it's why they close the Missouri season in mid-January. It would seem to support the idea that hunting harvest does in fact affect the quail population. Given the vast acres of quail habitat formerly, and I might add accidently, along with favorable weather through the 50's,60's, and 70's allowed us to do our worst, when it came to harvest. The conditions being able to out-produce the harvest. A luxury we no longer enjoy. A harvest no longer sustainable. Pheasants are bigger, more able and prone to travel to find superior habitat underutilized, or vacated when the original resident made a mistake, are more adaptable, in a word. Pheasants get by and thrive on amazingly sparse covers in which quail have no chance. They are polygamous breeders in the wild, to a larger degree than bobwhites, and we only shoot roosters. All reasons pheasants may survive and provide sport and are less suseptible to the human harvest. Unless we change our ways, quail are probably on the road to curiosity status.