The thousands of Minnesota hunters who will head west this fall — including to the Dakotas — to hunt pheasants and waterfowl will find less habitat and fewer places to hunt.

Habitat is shrinking as farmers continue to withdraw thousands of acres of grasslands from the federal Conservation Reserve Program (CRP) and convert them to crops. The loss of habitat not only directly affects hunters but impacts wildlife — pheasant numbers are down dramatically in North Dakota, South Dakota and Minnesota.

Since 2007 North Dakota has lost 1.8 million acres — or 2,800 square miles — of CRP. South Dakota has lost about a half-million acres — or nearly 800 square miles. And Minnesota has lost about 600,000 acres — or 937 square miles, including 100,000 acres that expire Monday.

In North Dakota, particularly, the loss of CRP will be noticed by hunters who use the state’s walk-in hunting lands, called Private Land Open to Sportsmen (PLOTS). Under the program, landowners are paid to allow public access to their lands. Much of that acreage is grassland enrolled in CRP. If farmers pull out of CRP and convert their grasslands to crops, the PLOTS contracts also expire. In the past two years, the state Game and Fish Department has lost about 250,000 acres from the walk-in program.

And if the trend continues, PLOTS acres could fall from 1.1 million at its peak three years ago to around 200,000 acres by 2018.

“This landscape change in North Dakota is the most dramatic since the first settlers came and started breaking the prairie,’’ said Kevin Kading, head of the Game and Fish Department’s private lands program. “How do we keep our wildlife populations in good shape when faced with grassland loss like this? It’s going to be really difficult.’’

And hunters this fall could notice something else besides fewer PLOTS parcels and a 30 percent decline in the ringneck population: The quality of the habitat on those PLOTS land is declining as other lower-quality lands are replacing the lost CRP acres. “It’s changing the face of our program,’’ Kading said.

At its peak, about half the 1 million acres in the program was also enrolled in CRP.

South Dakota walk-in

The situation with South Dakota’s similar walk-in hunting program isn’t as dire — yet.

The popular program, which also pays landowners to allow public access, remains at about 1.3 million acres this fall, despite the loss of CRP acreage. Part of the reason is that only about 180,000 acres of that total is enrolled in CRP. And a recent new program, the Conservation Reserve Enhancement Program (CREP), has helped offset losses. That program, which combines CRP with an additional payment to landowners to allow public hunting, has added about 80,000 acres of public access, said Travis Runia, South Dakota Game, Fish and Parks upland biologist.

“I’ve been surprised we haven’t lost more [walk-in lands],’’ he said. “But enrollments in the CREP program have buffered our loss of CRP.’’

But the loss of a half-million acres of CRP in the nation’s Pheasant Capitol could put more pressure on those walk-in lands, as hunters accustomed to hunting private lands find them plowed and planted with corn and soybeans. The ringneck population is down 64 percent this fall, mostly because of recent poor weather but also loss of habitat.

“We’re certainly concerned,’’ Runia said. “The long-term trends for habitat is scary. But there’s only so much we can do as an agency to combat landscape-level changes.’’

The state could lose another third of it’s CRP acreage in the next five years.

Minnesota program growing

Minnesota’s fledgling walk-in program, which was launched in 2011, will offer 20,000 acres this fall at 190 sites in 28 counties, up 6,000 acres from last year as the DNR tries to expand the program. About 129,000 acres enrolled in CRP will expire on Monday, but federal officials have enrolled another 26,000 acres, leaving a net loss of about 100,000 acres. Minnesota will have about 1.2 million acres in CRP this fall.

Officials aren’t sure, but the loss of CRP acreage may be limiting the agency’s ability to add to the walk-in program, said Mike Tenney, DNR prairie habitat team supervisor.

“We’re not increasing it [walk-in acreage] as fast as anticipated,’’ he said.

High commodity prices and skyrocketing land values are driving the conversion of grasslands back to crops, and few see any near-term change in the trend. Next year, some 205,000 acres of CRP contracts are scheduled to expire in Minnesota, Tenney said. All bad news for a state where the pheasant population is down 29 percent this fall.

Meanwhile, Minnesota hunters this year must buy a $3 validation to hunt those walk-in lands this season. So far, the DNR has sold 2,548 of them.