As Christmas Day approaches, the calendar heralds the end of another duck and goose hunting season in the northern Rockies.

But that hardly means the year's best waterfowl gunning is behind hunters in Idaho and Montana.

In fact, for the hardy 'fowler, hunting greenheads and ganders on open rivers and spring creeks flowing in steamy defiance of pipe-splitting cold fronts surging southward through these two states, the gunning during these late-season days can be nothing short of -- well, nothing short of epic.

If you're not willing to take my word on the matter, then how about the words of E. Donnall Thomas Jr. -- one of Montana's favorite outdoors writers?

In his wonderful wingshooting volume, titled Fool Hen Blues, Thomas writes the essay "Late Season" that chronicles the glories of duck hunting at the season's bitter end:

"When the mercury begins the day between zero and freezing, it becomes reasonable to expect productive shooting over decoys.

"And when the thermometer bottoms out and the truck won't start without a block heater and any suggestion of a breeze sends the chill factor slicing right through the last layer of your dignity, you can anticipate a duck hunt the likes of which you may never experience anywhere else."

Besides making me wish that I could write as superbly as he does, Don Thomas' written words inspire a willingness to step away from the comforting warmth of the fireplace and holiday preparations to venture outside and steel myself against Old Man Winter's icy wrath.

What for? For the chance at a duck hunt for the ages, one that will warm the soul for many bleak winter nights to come.

When the dying embers of another duck season arrive, the key, of course, is to find flowing water -- open water where wheat, barley, and corn stubble occur not covered by snow.

There will almost certainly be some big flocks of late-season mallards nearby, not to mention a smattering of other puddle ducks; late migrating divers, like goldeneyes; and big Canada geese.

With that in mind, here's a look at where, when, and how you can find December waterfowl in these two northern Rocky Mountain states.

MONTANA
Randy Renner -- a Bismarck, North Dakota, based regional biologist for Ducks Unlimited -- is a former Montana resident who understands full well the lure of late-season gunning for iced-up waterfowl.

"It can be pretty spectacular," Renner said. "It's some of my favorite hunting. There's just something about being out in the cold, lying in the snow and having a bunch of full-feathered birds decoy (into your spread)."

Take the hunt that Renner experienced a number of years ago on one of Montana's legendary spring creeks.

"I guess that was the first time that I had ever shot a spring creek, and it is probably one of my most memorable hunts of all time," Renner said. "The birds worked so well -- they really don't have a lot of options about how to decoy, since these are pretty narrow streams."

All in all, it was a hunt of a lifetime for Renner. To this day, he can vividly recall the snow on the ground, the cold weather and the brilliantly plumaged greenheads that decoyed with sheer abandon on that memorable outing.