Endangered species vs. agriculture: the fight for precious grassland
Published September 1, 1989 | September 1989 issue
Two years ago, Dennis Clark of South Dakota's Department of Agriculture was visiting the Minnesota Zoo when he heard a tour guide describe prairie dogs as being nearly extinct.
He had to be restrained by his wife.
"Nearly extinct?" he wanted to tell the tour guide. "Do you realize we have 200,000 acres inhabited by prairie dogs in South Dakota alone?"
But Clark didn't say anything. He already had enough battles about prairie dogs in his home statebattles that continue to be waged as South Dakota takes part in a controversial program to reintroduce an endangered species: the black-footed ferret, one of the rarest North American mammals.
The relationship between the black-footed ferret and the prairie dog is simpleblack-footed ferrets survive on prairie dogs. And, the relationship between prairie dogs and South Dakota's agricultural economy is also simpleprairie dogs eat and clip grasslands, thereby reducing grazing acreage for ranchers as well as threatening crops.
The economic/environmental conundrum: to successfully reintroduce the ferret, more prairie dogs are needed; but if prairie dogs are allowed to spread, valuable agricultural land may have to be sacrificed. The state is faced with the seemingly conflicting goals of preserving an endangered species and preserving an important economic base.
About 10 years ago, according to Lloyd Kortge, chief ranger, Badlands National Park, the black-footed ferret was thought to be extinct. After a ferret complex was discovered in Wyoming the animal was successfully bred in captivity and plans were made to reintroduce about 1,500 animals to the nation's grasslands.
Ten states are involved in the plan, and one of the prime spots for reintroduction is in the Conata Basin, Buffalo Gap National Grasslands, in western South Dakota (14 other South Dakota sites have also been considered). The Conata Basin also provides grassland for area ranchers.
In order to flourish after its reintroduction, each ferret in a colony of about 100 needs 30 to 60 acres of prairie dogs. That means in some areas the prairie dog population will be allowed to grow; after all, Kortge said, prairie dog eradication programs helped lead to the ferret's near-extinct status. According to the reintroduction plan, prairie dog acreage in Conata Basin may be increased from 2,000 to 5,500.
"There is a feeling that the prairie dog population is too low in South Dakota," Kortge said, adding that the population is continuously dropping.
And the ranger, while agreeing with Clark's estimate of about 200,000 prairie dog acres, takes issue with the stability of those acres. Of that number, 80 percent of the prairie dogs are on Indian land, about 15 percent are on private land and about 5 percent on public land. The problem, according to Kortge, is that there is no guarantee that the prairie dogs on Indian and private lands won't be eradicated.
According to a South Dakota Game, Fish and Parks Department report, the Pine Ridge Reservation reduced its prairie dog acreage from about 268,000 to about 57,000 from 1983 to 1987. Also, the Oglala Sioux Tribe officially requested on May 3, 1989, that no ferrets be introduced on the Pine Ridge Reservation.
"That [200,000] acreage isn't real secure," Kortge said.
But for the Pine Ridge Reservation and much of the agricultural industry, a decreasing prairie dog population provides economic security, according to Clark. In 1980, when the state had 700,000 acres of prairie dogs, one study showed that South Dakota's ag economy lost $9.6 million in revenues from prairie dogs because of damage to pastures, rangeland and crops (as well as $9.8 million from pocket gophers and $7.8 million from ground squirrels).
In 1984, those direct losses from prairie dogs dropped to $4 million, but indirect costs to other related industries may have pushed the total to $13 million, Clark said referring to a South Dakota State University study.
The fear in the ag industry, according to Clark, is that the ferret reintroduction will be so successful that they will spread and require even more prairie dogs. And during dry seasons, like the ones recently experienced by ranchers, any available grassland is needed to maintain herd levels, he saidnot to support more prairie dogs.
"Ranchers are pretty liberal," Clark said, and they accept the presence of a small prairie dog town "here and there." But they must be properly controlled, he said.
There is a problem of perception when it comes to prairie dogs, according to Kortge. The state places the prairie dog under the category "Declared Pest." Indeed, the state has removed itself from working groups established to reintroduce the ferret. In an April 1989 letter to The Wildlife Society, Gov. George Mickelson said:
"I cannot support a reintroduction program at this time because of the cost associated with such reintroduction and the potential negative ramifications on the economic interest of our farming and ranching communities. I further believe any plan to reintroduce a fragile species such as the black-footed ferret into the wild is not in the public's best interest, nor is it compatible with multi-use of public land in any practical sense.
"Recovery of black-footed ferrets should continue, but not for reintroduction into South Dakota native prairies."
However, according to Kortge, the prairie dog towns that dot the nation's grasslands are "hot spots" on the Great Plains, and their inhabitants are not necessarily "pests." According to one report: "Prairie dogs have been shown to enhance wildlife habitat, adding to species diversity and abundance, and to increase protein content of vegetation."
But despite the state government's protests and unwillingness to work with the reintroduction effort, the ferret may find itself back in South Dakota's grasslands as soon as 1991 because of federal laws governing endangered species.
"The prairie dog remains largely an emotional and unsettled issue," the National Park Service said in a recent report. And the ferret is inextricably linked to that issue.
"The whole thing is not easy," Clark said. "If things go unchecked, all of a sudden we're back to 700,000 acres [of prairie dogs]. That's the fear."