Wolves, not bullets, should be used to cull the elk herds that move through Rocky Mountain National Park, according to a lawsuit filed against the Interior Department and National Park Service.

Behind the lawsuit (attached below) filed Tuesday in U.S. District Court in Denver is WildEarth Guardians, which maintains park officials didn't adequately consider wolves when they debated how to reduce the size of the elk herds.

Exactly how many elk roam Rocky Mountain varies throughout the year. While the range of animals in recent years has been pegged at anywhere between 2,200 and 3,100, according to wildlife biologists, during the past five winters the average count has been between 1,700 and 2,200. The park's objective is to keep the winter population between 1,600 and 2,100.

The pressure the herds put on the park's stands of aspen and willows led earlier this year to the decision to use sharp-shooters and biological agents to reduce the elk population. Though the Park Service long has prided itself on letting "natural processes" govern the ecosystems contained within the national park system, those days are fading away in the Lower 48 as private lands turn into subdivisions and predators are driven off.

But those at WildEarth Guardians don't think the landscape in and around Rocky Mountain is beyond supporting a few wolf packs that could eliminate the need for sharp-shooters.

“Without wolves to keep the elk population moving around, aspen and willow face extinction in the park” said Rob Edward, the director of carnivore recovery for WildEarth Guardians. “Sadly, the government has chosen bullets over wolves, and politics over science.”

The group contends that the Park Service"flatly ignored scientific evidence generated from Yellowstone National Park and elsewhere that linked the decline of aspen and willow in Western ecosystems to the eradication of wolves from the West. That same scientific evidence shows that the restoration of wolves has yielded a swift, dramatic and sustained benefit to native plants."

The lawsuit also charges that the Park Service has an obligation to further the conservation of endangered species under a little-used provision in the Endangered Species Act.

“The Park Service should accept that their elk problem stems directly from a lack of wolves in the region,” said Mr. Edward. "It's time to restore the balance of nature in Rocky Mountain National Park."

It really wouldn't be that difficult of a task, according to the group, which believes the Park Service should work with the U.S. Fish and Wildlife Service to develop a cooperative wolf recovery plan for Colorado. Such a plan could return wolves to the park and several other locations in western Colorado identified by scientists as prime reintroduction sites, the group believes.

Such a strategy was developed for Yellowstone and areas of central Idaho where wolves were returned, said Mr. Edwards.

According to WildEarth Guardians, much of the land surrounding Rocky Mountain National Park is publicly owned, not private property. Of the lands within 15 miles of the park border, only 23 percent is privately held, it says.

"Just as we must restore fire to balance and rejuvenate wild landscapes," said Mr. Edward, "so must we restore wolves to the American West."