NEAR PRESHO, S.D. — In the nearly half-century he's lived in South Dakota, John Cooper has seen countless beautiful prairie sunsets. But none perhaps prettier than one on a recent late afternoon that arched wild hues of orange, red, yellow and crimson across a darkening sky.

"I never get tired of that," Cooper said, nodding toward the colorful horizon, a 12 gauge double-gun slung over one shoulder and his Labrador retriever walking ahead.

However barren in appearance, South Dakota prairies pulse with life. Eagles, hawks, prairie dogs, pheasants, ducks, geese and sharp-tailed grouse thrive here. So do coyotes, a pack of which yipped their singsong appreciation for the coming night as Cooper sleeved his scattergun following a long afternoon's pheasant hunt.

The retired director of South Dakota's Game, Fish and Parks Department, serving 12 years under two governors, Cooper also has been a U.S. Fish and Wildlife Service enforcement agent in North Dakota, South Dakota and Nebraska.

In those states, he traveled nearly every highway, byway and country road during a 22-year career as a federal officer.

So when he says change is occurring to the South Dakota landscape at a rate never seen before, with far-reaching implications for wildlife and people, he speaks with a perspective few share.

"What has happened here in the past four years is unprecedented," Cooper said as he and I climbed into my pickup and rumbled over a dirt two-track. "Anyone who thinks South Dakota can continue to produce the pheasants, ducks and other wildlife it has in the past just doesn't know what's going on here. You're quite possibly witnessing the end of an era. Some of the nation's last, best prairies and potholes are going away."

Responsible for the changes is what farmer, rancher and hunting outfitter Steve Halverson of Kennebec, S.D., calls a "perfect storm" of high commodity prices, rising land values, breakthroughs in crop engineering, a seemingly feverish desire by some eastern South Dakota farmers to drain their lands of water, and relatively paltry federal farm bill conservation incentives.

"I honestly think that unless something unexpected happens, we may never see the high pheasant populations again that we've seen in recent years," Halverson said.

Duck production in the state is also at risk. The Natural Resources Conservation Service in Brookings, S.D., has a backlog of more than 4,500 requests by farmers and ranchers to issue wetland determinations on their lands -- up nearly tenfold in only four years.

Most appeals are from landowners wanting to increase their tillable acres by draining water from their property. "The requests have been doubling each year," said Janet Oertley, NRCS state conservationist in Huron, S.D.

In 2011, with prices hovering around $6 per bushel, South Dakota farmers planted about 5.2 million acres of corn, a 650,000-acre increase from 2010.

"What's driving it is greed," said farmer and rancher Jim Faulstich of Highmore, S.D., who believes a balanced landscape is critical to South Dakota's economic well-being. "I've lost some friends over comments like that. But there's no other way to describe it."

Continued cropland expansion will affect most South Dakota wildlife, experts say, including songbirds such as grasshopper sparrows, sedge wrens, vesper sparrows, dickcissels, savannah sparrows, lark buntings, chestnut-collared longspurs and bobolinks.

Prairie ecosystems need birds to distribute seeds of native grasses, whose deep roots hold the fragile prairie soil together, particularly during heavy rains and spring flooding.

Pheasant -- and pheasant hunter -- declines also are expected as crop acres increase, particularly in years such as 2011, when a tough winter and wet spring helped push the state's ringneck population down about 40 percent from 2010.

"When we had between 8 million and 9 million pheasants, as we did in recent years, we could count on about 85,000 resident pheasant hunters and 115,000 nonresidents," Cooper said. "With continued habitat loss, we'll lose [numbers in] both [categories]."

Towns small and large will feel the pinch.

"The $200 million that pheasant hunting brings to the state each year can't match the state's agriculture economy," Cooper said. "But the pheasant money trickles down to small-town cafes and motels and gas stations throughout the eastern half of the state. Ag money by comparison is much more concentrated."

Changing economy

In 1985, when the Conservation Reserve Program (CRP) was first included in the federal farm bill, corn was about $3 a bushel, recent borrowing rates had hit 20 percent and many farmers were struggling financially.

CRP proved attractive at the time because it guaranteed cash to farmers who set aside marginally tillable and highly erodible acres, planting them instead in cover crops to benefit soil, water and wildlife.

South Dakota CRP lands peaked at about 1.7 million acres in 1997. But as corn prices have risen -- fueled in part by federally subsidized ethanol production -- CRP has declined in the state to about 1.1 million acres, with 200,000 or more acres expected to leave the plan this year.

"There's no longer any incentive to stay in CRP if you're a farmer," said Curt Korzan of Kimball, S.D., who with his wife, Lorie, and two grown sons, Corbin and Cody, farms and runs a pheasant hunting lodge over 3,500 acres, about 80 percent of which is in wildlife habitat.

"Around here," Korzan said, "CRP only pays $50 to $60 an acre, while farmland rental rates are $150 to $160 an acre."

Korzan said a 1,000-acre tract near his operation recently sold for $3,000 an acre -- $2,500 more than the owner paid for it.

"It was 100 percent habitat, perfect for wildlife, with 12 groves of trees," Korzan said. "The new owners are going to bulldoze all of it and put it in corn."

If South Dakota were only losing CRP acres, pheasant, duck and other wildlife losses would be significant but somewhat manageable, with the help of other government and nongovernment conservation programs.

But vastly larger tracts of unprotected grasslands not enrolled in CRP are being plowed, too.

A 2007 study by the federal Government Accountability Office found that even while CRP protected 1.7 million acres in South Dakota, the state lost another 1.8 million acres of prairie to newly tilled croplands.

Taxpayers -- who kick in about 60 percent of farmers' crop insurance costs ($7.1 billion in 2011) -- pick up a big part of the tab for cropland expansion, according to the GAO.

Crop insurance minimizes the chance farmers will lose money when new ground is broken.

"As a result, what you're looking at is the transformation of South Dakota into something more closely resembling northern Iowa or western Minnesota, where virtually all wildlife is gone," Cooper said.

Science makes it possible

Just three weeks ago, the U.S. Department of Agriculture cleared for sale Monsanto's latest genetically engineered marvel: drought-resistant corn.

Doing so, the agency delivered a Christmas gift to South Dakota and other dry-land farmers who want to plant corn where none has grown before.

Moisture shortfalls are to blame for 40 percent of North American crop losses, Monsanto estimates. It's also the reason many South Dakota grassland ranchers traditionally have run cattle on their semi-arid lands instead of growing corn.

But crop engineering now boosts a farmer's chance for profit even on those marginal lands. It also raises the value of those properties, in some cases to $6,000 an acre in eastern South Dakota.

The result, said Carl Madsen, a retired U.S. Fish and Wildlife Service biologist living in Brookings, is that "the intensity of land use in South Dakota is moving west into the grasslands."

"The genetically modified crops got the ball rolling," he said. "Then the tile drainage started to move into South Dakota in a big way. Add to it $6-a-bushel corn. For wildlife, it's a bad combination."

Said Korzan, the farmer and hunting operator who lives near Kimball, S.D.: "The mentality of a lot of young farmers in South Dakota in particular is that they're going to till everything they can. They've never seen a bad year. They will. Maybe it'll be because we overproduce. Maybe because switchgrass will someday replace corn in ethanol. Either way, the bank will still want payments on that $250,000 tractor and $350,000 combine."

New farm bill pending

South Dakota wildlife will suffer further if the farm bill being debated in Congress fails to link conservation with farmers' crop insurance, Madsen said.

"The ag industry is lobbying against it, and whether Congress has the stomach to stand up to them, I don't now," he said. "Right now, to participate in federal commodity programs, farmers have to abide by certain wetland and grassland protection rules.

"That's not going to happen in the next farm bill, because Congress needs to cut costs. Our only chance for conservation is to require farmers who take out crop insurance -- most of which is paid for by taxpayers, anyway -- to not drain wetlands or plow under fragile grasslands."

Faulstich supports the idea.

"I'll use myself as an example," he said. "In 2010 I had the most profitable return per acre of corn I've ever had, and I still got direct payments and subsidies from the government. It's really unfair to taxpayers and to people who live on the land who are conservation-minded."

John Cooper considers himself one of the latter.

But after he and I followed three pretty good dogs on a recent afternoon without putting up a rooster pheasant -- something virtually unheard of in South Dakota -- he wondered whether the outing had been an omen of things to come.

"I hope not," he said.

Dennis Anderson • danderson@startribune.com