Prairie dogs best enjoy these sunny winter days.

Thousands of them won't be around to enjoy them this time next year.

The U.S. Forest Service plans to kill 10,000 of them where the dog colonies are encroaching on private and non-federal land adjacent to the McKenzie District of the Little Missouri Grasslands.

The plan to prevent the dog colonies from spreading off the grasslands onto private and state land is part of the new grasslands' management plan's good neighbor policy.

The killings - the first in a dozen years - was to have done by now, but the Forest Service is giving additional thought to the project and has a third, gentler alternative in mind.

District range specialist Gary Petik said the first two alternatives - no action, or kill encroaching prairie dogs on roughly 310 acres - generated about 70 comments from sport shooters to environmental groups when a draft environmental assessment was released last summer.

Based on those responses, the agency plans to come with another alternative that would reduce encroachment and reduce the scope of the kill.

"It would still help maintain the buffer zones, but with less poison," Petik said.

He said it's too soon to spell out the details of the third alternative, because the agency is still gathering information on how it would be carried out.

He said the agency should have the third alternative written by the end of February.

In the meantime, it will decide whether to start over and release the third alternative as part of a draft assessment, so the public can comment, or release it as part of a final assessment, which can only be appealed.

In all, the Forest Service plans to treat 11 prairie dog colonies with poison, but only if the neighboring landowner also poisons the colony on his side of the fence.

Another nine colonies will be monitored over the next several years to prevent encroachment on private and other non-federal land.

Petik said the agency is still evaluating whether another three colonies should be poisoned, or monitored.

The agency plans to move forward with the project next late fall and early winter, after migrating birds have moved through.

The timing is intended to prevent unintended poisoning of other species.

The zinc phosphate poison is mixed with rolled oats and set out at mouth of the dog burrows. Most of the prairie dogs will die underground in their burrows.

In all, the McKenzie District has about 2,000 prairie dog acres out of 500,000 acres in the district.

One area, the prairie dog colony that occupies the largest area of continual federal grasslands, has been identified for the possible reintroduction of the black-footed ferret.

(Reach reporter Lauren Donovan at 888-303-5511, or lauren@;westriv.com.)