I did the summary a couple yrs. back. Little changes. Enjoy. I would suggest you find a good map and look for government lands. I 90 you can go thru SD, swing down to Rosebud (Sioux/ they prefer Lakota), google for current charges. Or go north to Standing Rock (Northern Cheyenne). ND there is the Roosevelt Park (NO shooting in park!!!) and adjacent public lands. Wyo, Thunder Basin is in NE corner. I never got to Montana. Ran out of ammo in Wyo. Lots of shooting available at any range of costs. You just have to "do your homework." Many Rocky Mountain guides offer p'dog shooting to amuse the hunter who has filled a tag or two. Will separate. Accomodations to your taste/budget... Luck
To summarize: the prairie dog is the tree squirrel of the grasslands. I believe I have heard that in the Brit Isles the gray squirrel is more common than the red, well, here the prairie dog has no trees so it lives in holes in the ground like rats, mice, rabbits, its cousins, all rodents. No bushy tail. Eats grass. Actually aerates the soil and in a few studies the cattle grazing gain more/grow faster on prairie dog ground... Unfortunately the stockmen are slow to learn and have demanded poisoning to exterminate the furball. Fed biologist told me that 90% of the p'dogs that died in the 20th century died of government spread poison. (Rodent, they breed like "rats and mice.")
TWO BIG WARNINGS: BEWARE!!!: #1). There is "plague" in the furballs. Don't get close or handle pieces. Cousin to bubonic plague. Cureable with antibiotics. Carried by fleas that jump from deceased and cooling bodies to warm bodies. But why bother. Let the scavangers have the pieces. Recycle.
#2)There was a weasel called the Black footed Ferret that was almost extincted by a house cat disease. There are areas that are closed to shooting by Fed regs to support the re introduction of this weasel... Only likes to eat prairie dogs! Make sure you are not shooting there or you might find yourself in striped sunshine... Bad news...
You are looking for "short grass prairie." There are three. Tall grass. Ohio. Indiana. IL. Going west, "mid grass prairie." Iowa. Missouri. Eastern Dakota. Now the exact line moves each year with average rainfall. "Short grass prairie" is the old "cowboy/cattle country" of the westerns (made in California mainly, ha,ha). Texas/Mexico north into Canada. East Slope of the Rocky Mountains. But try to get 1,000 rounds of anything in Mex or Canada or try to bring it in... (ha, ha). Never shot in Oklahoma or Texas but told it is pay to shoot. Land pretty much "spoken for." "Northern Plains" settled much later, much "government land" (no one wants to pay taxes on a mountain top basically or real rough valleys, etc. "The moors" in Sherlock Holmes type fiction.), etc. Eastern Montana. Most of Wyoming. East Colorado. Western Dakotas. West Nebraska. West Kansas. Etc. The old "cattle drive trails" of movies and t.v. (Rawhide, where Clint Eastwood got his start... Lonesome Dove... The movie "Thunderheart" with Val Kilmer was filmed on the Native American Indian Reservations of South Dakota. Plot is a Hollywood hack job of some facts but if you look at the background you will see the land form. Badlands National Park area.)
US government has "grasslands" where the law requires management for multiple uses which includes shooting/hunting for now anyway. SW Kansas, Cimmaron Nat. Grassland, for example... Often one use is renting to pasture users--i.e. "grazing." This area cows mainly. Rarely sheep. Many, many wild dogs, "coyotes," that will kill sheep. SW corner South Dakota (SD) "Buffalo Gap Nat. Grasslands." These are open to anyone for anything legal. Not a good place to be alone with a break down so I cannot recommend you start here. You might find yourself
As the government took the last of the land away from control of the last of the "wild" Native Americans, they were forced onto reservations. The only "indian war" the U.S. Army lost was to Red Cloud, Chief, Lakota Indians, better known as "Sioux." He fought over the Bozeman Trail [(to Bozeman Montana)... typical government... they sent diplomats to get permission at the same time they sent soldiers/contractors to build the forts along the trail they didn't have permission for yet...]. I was told by resident of SD that the more educated Sioux were settled from east to West. In SD (South Dakota) that meant the Rosebud got the "indians" who knew what was good for them while the ones that tried to stay "wild" [with Crazy Horse as a "war leader" but he was never a "chief"] had to be starved into submission and ended up on the most western reservation, the Pine Ridge. SW SD.
O.K. the Native Americans "market." [Fuss among themselves like a herd of Chicago Democrats--don't get me started, Capone who was Italian/Sicilian vs. Obanion, Irish -- all criminals... Not to mention the "bought" politicians of all flavors] I had a fed tell me that while one group of "injuns" was seeking money to help build the business of hunting/shooting p'dogs another group was seeking money to "kill them all" to make for better pastures... Valentine, NE is just south of the Rosebud and home of "Lock, Stock and Barrel," a gun supply store... might want to google them.
By name so you can do your research with google or
South center SD, Rosebud Reservation (Rez as spoken by Natives). I believe I first got their name from Bruce Hodgdon Sr, now gone--yes, Hodgdon powder Co. Many years ago. Due north around Pierre SD, Lower Brule Sioux. Farther north, Northern Cheyenne Rez / Standing Rock Rez. Eagle Butte, SD has been a center of shooting. South West corner, SD, the Pine Ridge Rez. [They have a drinking problem covered in the newspapers. Still grieving Crazy Horse and Sitting Bull? One inet business, lakotamall.com. I believe there is a couple guides available there.]
Farther north, North Dakota (surprise), In the west a former president, Theodore Roosevelt, lived and worked cattle and recovered from the death of a wife... and now there is the Theodore Roosevelt National Park and grasslands. Beautiful country. Cooler at night. Something to think about. Fort Yates is another town to think of.
Outside SD and the VHA (Varmint hunters Assoc. mentioned prior--varminthunters.org I think) there is very little well organized. Most big game guides will find you shooting until your ammo runs out after you fill a big game tag. Some offer p'dog shooting separately. One example [disclosure, his grandfather was an armey buddy of my grandfather, WW I, yes I] Ron Scherbarth, Rocking Heart Ranch. Big game guide and passable taxidermist.
MOntana, nothing organized. Shooting around Zortman was widely discussed. I believe you ended up on the Fort Belnap Rez. (Blackfoot Indians?)
Colorado. Here the US government has taken up much space for army bases... Brought along a bunch of tree huggers and bunny lovers. One tv special showed "catch and release" of prairie dogs! [That is like "catch and release of mice in your basement. To me... DUMB!!!) Plenty of p'dogs. Ask in the small towns or farm stores. Find the people that don't think of them as pets. I have had them in my lap. They are loveable little rats, not that little for rats. Fed them peanuts. Tourist trap. They ran my fingers with their teeth until they found the peanut and then bit... Amazing.
West Kansas. More of the same. Grazing. Rural Welcome (open arms). Cimmaron web site has a "please don't shoot the p'dogs" notice on it, but request, not order.
Wyoming is my favorite. I have relatives near. Wide open. Cattle is second to "oil." No license or permit required for US citizens anyway. (Like I said "ask.") Thunder Basic National Grassland between Douglas Wyoming and New Castle Wyoming supposedly had a p'dog town that was 26 miles in diameter. There is plenty of shooting in the Cheyenne, Wyo area, but also, as seat of government, more bunny huggers ...
Since I have family in the Wyo/SD/NE area that is where I go. Never got to Montana. Ran out of ammo. (Reloads). SD and NE will want "non resident license fees." I'm cheap. Drive a few miles and shoot without any. I have composed this deliberately using all the names with which I am familiar so you can search much and enjoy the "dicovery." Spotter? Not needed. (Purpose is that you take turns and let one gun cool while spotting!!! Otherwise a barrel won't last a day...) Shots. You may hear of 1,000 round days per shooter. Possible? Yes. Recently? No. There has been a 10 year drought that cuts way down on the grass available and inspires more poisoning. Things should build back fast, but things slower now. .223 is good. I have made 600 yard hits. No, I did not say on the first shot. Black Hills Ammo is in Rapid City, SD, fyi. Sells reloaded mil. cases less expensive. No idea about importing guns or ammo. Some guides can set you up with a bench, press, tools. Have to ask. I am a bit winded. ENJOY. Luck. Happy trails.