A state poisoning program aimed at killing prairie dogs that migrate from infested public land to adjoining private ranches could be delayed and hampered by continued rains and plentiful grass, a Game, Fish & Parks Department official said Wednesday.

But GF&P Regional Supervisor Mike Kintigh of Rapid City also said the spread of plague among prairie dogs in heavily infested parts of the Conata Basin south of Wall could cut numbers enough to reduce the need for state control in some areas.

"In those areas that are plagued out, I'd expect we won't have to go in and treat them," Kintigh said. "I'd expect the number of acres we treat this year would be down, both because of the plague and because of our past treatment efforts."

The state prairie dog management plan, which was approved in 2005, includes assistance to landowners who believe they are being damaged by prairie dog encroachment from adjoining public or private ground. The plan involves direct poisoning by the state and contract control agents and, in some cases, financial incentives to compensate landowners where prairie dogs are allowed to remain.

Federal regulations allow poisoning in the program to begin July 1. But Kintigh said the work typically starts later than that. And this year, it could be delayed even more than usual because of the plentiful grass growth in western South Dakota.

That grass is a blessing for ranchers but a potential complication for prairie dog poisoning efforts that rely on poisoned oats, Kintigh said.

"When there's abundant food out there, green grass, for these prairie dogs, there's a concern they'll be less likely to pick up the bait," he said. "And we're only allowed to treat a given area once a year. So, if we go in when the grass is green, and they don't take the bait and we get a very poor kill, we'll have to sit and watch until next year."

Federal grasslands managed by the U.S. Forest Service in the Conata Basin have been at the center of prairie dog problems, and landowners have been especially vocal about the damages. The area also is affected by an outbreak of sylvatic plague, which has killed prairie dogs across thousands of acres.

Federal officials allow the state to poison prairie dogs on a buffer zone up to a half mile into federal grasslands adjoining private land that is to be treated. But prairie dogs on the federal land can't be poisoned until after Oct. 1, so the state tries to hold off on treating adjoining private lands until both sides of the fence can be poisoned, Kintigh said.

"Ideally we do that, because it's more effective to treat both sides," he said.

Control crews first deposit a few untreated oats at each active prairie dog hole, then come back in a few days and leave oats treated with the poison, zinc phosphide.

"They pick up a couple kernels of that, and they die," Kintigh said. "We can get up to a 95 percent kill or better in most cases."

It helps if the prairie dogs don't have other available food options, such as fresh, green grass. Rain can also diminish the effectiveness of the poison, if it falls after the treated oats are applied.

"We've been blessed this year with rain," Kintigh said. "And if it continues to rain, that could become a concern. But we can wait a while. And there's some research that indicates the best time to apply is after a hard frost."

Send your comments

Landowners with complaints about prairie dog encroachment from public lands should contact the Department of Game, Fish & Parks by Aug. 15. The contact number is 605-773-5913 in Pierre. Landowners interested in the financial incentive option should use the same number by the same date.

If the prairie dogs are coming from adjoining private land, the affected landowner must either send a formal complaint to the local weed and pest board or contact state agriculture officials at 800-228-5254 or on the department's Web site at state.sd.us/doa/das/. The mailing address is South Dakota Agriculture Department, 523 E. Capitol Ave., Pierre, SD 57501.

To see the plan:

The South Dakota Prairie Dog Management Plan is available at www.sdgfp.info/Wildlife/hunting/PrairieDog.htm or by calling the GF&P Wildlife Damage Program at 605-773-3387.

Contact Kevin Woster at 394-8413 or kevin.woster@rapidcityjournal.com