Paul Harvey, was one of my favorite radio guys, he had his "Rest of the story" segments.
This is the rest of the story on the Bianchi pheasants. Under the guidance of the
"Foreign Game Bird Introduction Program" in the late 1950's and 1960's wild and more adaptable strains of the true pheasants (ringneck type) were brought in to expand the wild ringneck population. These true pheasant included Japanese, Korean, Persian and Bianchi (Afghan Whitewing pheasant). Those new and wild strains were never intended to stay pure. But only to add agility, wary/alertness and adaptability to the ringneck gene pool.
In New Mexico, pen raised ringneck pheasant were first released in 1916 and the Bianchi pheasants were added to the low sparsely ringneck population in the early 60's. The Bianchi pheasants were like a super charge to the wild pheasant population because the Bianchi pheasants instinctively knew how to avoid predators.
Years ago they had this old theory that the ringneck pheasants would not hatch in warm or humid areas or areas poor in calcium. I don't know how they came up with that theory because at the time in the 50's they had wild ringneck pheasants in the California and Mexicali, Mexico.
Thirty-seven years I spoke with the top game biologist in Texas, he explained in me that under the program they brought in three pheasant strains in to expand the wild pheasant range the white winged (bianchi pheasant) the pure Persian (Iranian) pheasant (the pure Persian is just as wary/alert as the pure bianchi) and the Korean ringneck pheasant.
They never intended for these pheasants to stay pure they only wanted to add alertness and expand the wild pheasant range.
Fifty to sixty years ago if you lived south of I-40 (old Route 66) in the Texas panhandle and you wanted to see and hunt wild pheasant you would have drive 700 miles to South Dakota to find them.
Illinois in the 1960 also received pure Japanese pheasants for Wabash county. See article:
http://ilacadofsci.com/wp-content/uploads/2014/01/061-54-print.pdf
If those wilder strains of pheasants can make living and reproduce along the Rio grande river, the Canadian river and the Pecos river they can make a living in other areas void of wild pheasants like farming country of Kentucky and Tennessee.