FORT RIPLEY — Since the 1998 introduction of wild turkeys into this part of Minnesota via trap-and-transplant from the southern part of the state, the turkey population has grown beyond most people's expectations. It's now common to see the big birds in just about any suitable habitat.

In those flocks a person might glimpse the occasional turkey bearing mostly white or gray feathers.

What? Did a few of Minnesota's wild turkeys have intimate encounters with Thanksgiving Butterballs? Is there too much bleach in the wild turkey gene pool?

Not so, according to most turkey experts.

"The partially white or smoke-phase turkeys occur naturally," said Tom Glines, Minnesota's senior regional director for the National Wild Turkey Federation. "The white or gray feathers are black-tipped and the birds are beautiful."

There has been some concern that landowners have released pen-raised turkeys into the wild -- a practice that is illegal without a permit -- and that some of those captive turkeys have bred with the wild turkeys, resulting in the smoke-phase turkeys.

There is no hard science to back up those concerns.

What is known is that the wild turkey has four distinct color variations from what is considered the usual plumage. They are the smoke phase, the erythritic or red phase, the melanistic or black phase, and the true albinos, which are pure white with pink eyes. Although these color variations are uncommon, the smoke phase is the most frequently seen. Recessive genes or mutations account for the color abnormalities.

Glines estimates roughly one in 100 wild turkeys is smoke colored. In my experience hunting and photographing wild turkeys in central Minnesota, I would guess about one in 70 wild turkeys are smoke colored. I've seen as many as three smoke-phase birds in a flock that numbered about 20 "normally colored" turkeys.

As Glines noted, smoke-phase wild turkeys are a visual delight. Their heads are light blue or gray and their caruncles a faint red or pink similar to a normally colored turkey. The body feathers, splendid as they are, feature a varying amount of white or light gray feathers tipped with black as if dipped in ink. The tails on most of the smoke-phase turkeys I've encountered were not white; rather the tails were a shade or two lighter than a standard turkey's tail.

Smoke-phase wild turkeys can produce offspring that are partially white or normal-colored. Some broods can have some of each. Oddly, about 95 percent of smoke-phase turkeys are hens.

I have never positively identified a smoke-phase tom turkey. If I have seen a male smoke-phase wild turkey, it was before the bird had aged enough to grow a beard, or it had presented me with just a glimpse from behind. I find that odd because I know I've seen more than 100 smoke-phase birds over the years. You'd think I would have encountered at least one male. It's on my yet-to-see list.

I have never known anyone in this area to kill a smoke-phase gobbler, but I would assume a few smoke-phase hens have been bagged during the fall hunting season when females are legal to shoot.

A quick Web search confirmed my experience and the rarity of male smoke-phase wild turkeys. I found only one posting of a splendid smoke-phase gobbler shot by a fortunate archer.

Until genetic research proves otherwise I'd like to believe the attractive smoke-phase turkeys meandering the bluffs of central Minnesota are not the results of roaming, romantic Jennie-Os.

Bill Marchel, an outdoors photographer and columnist, lives near Brainerd.