As Call of the Wild Returns, Changes Echo Across Nature : Ecosystem: Wolves reintroduced to Yellowstone show promise in helping restore ecological balance.

High on a ridge and knee-deep in snow, biologist Doug Smith studied the savaged carcass of a bull elk and saw unmistakable evidence of a struggle to the death.

Blood streaked the snow. Tufts of matted brown hair were scattered everywhere. Fat-depleted marrow in the leg bones suggested the elk was suffering from malnutrition when it was attacked. And there were huge, dog-like paw prints surrounding the carcass.

“This elk was killed by wolves--a great event,” Smith said. “Kills like this will root the wolves to the area, which is exactly what we want.”

It was one of the first confirmed kills by wolves imported from Canada to restore the ecological balance here and in the wilderness of central Idaho under a $7-million federal project that no one was certain would succeed.

Now, biologists are cautiously optimistic. And each day they learn more about the impact that these mobile, efficient hunters will have on the plants and animals that exist in the nation’s oldest national park.

Air and ground observations suggest that the radio-collared wolves are faring well, loping through forests and plains in packs, feeding on elk and bison, mapping territories with scent marks and communicating with lingering howls.

But the wolves’ problems are far from over. The project has come under criticism by the new conservative majority in Congress as typical excess by environmentalists and federal enforcers of the Endangered Species Act. And ranching interests are pursuing legal remedies to halt the project, which they say could deplete livestock.

For now, biologists are focusing their attention on how the wolves are adapting to their new environs. The surprise is that some of the 14 Yellowstone wolves--nine males and five females--took down an adult buffalo, a species alien to the rolling hills of Alberta, Canada, where the wolves were captured in January.

That kill elated Yellowstone authorities, who had long hoped that bringing the top predator in the food chain back to Yellowstone would reduce the herds of bison expanding their range beyond park boundaries. Local ranchers fear Yellowstone bison will infect domestic cattle with a highly contagious disease known as brucellosis.

“Wolf kills Yellowstone bison! Wonderful news!” Yellowstone Supt. Mike Finley shouted soon after hearing the news, thrusting a fist into the air triumphantly.

“Many people do not believe that natural regulation is an effective way of controlling Yellowstone bison,” he said. “Well, this taking by wolves disproves that.”

Another surprise: The wolves didn’t bolt for Canada when biologists opened the gates of their acclimation pens here. Although three of the wolves temporarily roamed seven miles north of park boundaries, their return last week allayed fears of their being shot by Montana ranchers.

A month ago, one of 15 wolves released in Idaho was found shot to death on a ranch. An investigation into that shooting triggered a confrontation with sheriff’s authorities, who claimed federal agents failed to notify the ranch owner before searching his property.

“The wolf hysteria around here is exasperating,” John Varley, Yellowstone’s chief biologist, said, sighing. “But the good news is that wolves are back. Yellowstone without wolves was like a marching band without a drummer.”

Of the thousands of varieties of wildlife that were in Yellowstone when the park was established in 1872, only wolves were missing. Now biologists are watching as ancient patterns are renewed among the park’s natural communities.

No one can say with certainty how great the wolves’ ultimate impact will be on Yellowstone--its ecosystem is far too complex for that. But Varley said some changes in the 2.2-million-acre park’s food webs are already under way, and “they have drama.”

A grizzly bear, coyotes, bald eagles, ravens and armies of beetles have been seen dining on the carcasses of large mammals killed by wolves. Bluebirds and magpies have been feasting on the beetles. Those birds will be joined by warblers, nuthatches and Western tanagers as the weather warms.

Now that wolves are once again stalking prey here, the relaxed nature of Yellowstone’s vast herds of elk, deer and bison will become a thing of the past.

Biologists predict that the elk population, which numbers close to 50,000, may decline by as much as 20% because of wolf kills. Bison, which number about 3,500, may be reduced by 15%, mule deer by 19% and moose by 13%, biologists say.

Some believe that keeping elk and deer on the move will ease stress on the willow thickets and aspen saplings that they devour. More willows and aspens, experts say, could one day mean more perching birds and insects--including butterflies.

By culling herds of weak and diseased animals, wolves will actually strengthen the genetic pools of prey populations, said Hank Fischer, northern Rockies representative of the conservation group Defenders of Wildlife and author of a soon-to-be-published book called “Wolf Wars.”

“In the mid-1980s, bighorn sheep in the park suffered from pinkeye, which killed off 50% of the herd,” Fischer said. “If we had a wolf population back then, the first sheep to go would have been the sick ones, and the disease might not have spread to the entire herd.”

Biologists also expect wolves to prey on the vast coyote population here, leaving more rabbits and other rodents for hawks, eagles and owls. Fewer coyotes also will mean more foxes, which adapt well in wolf-inhabited regions. But how will wolves and rival carnivores such as grizzly bears and mountain lions get along? Research at Montana’s Glacier National Park, where all three species come face to face, may provide some answers.

“In Glacier, there is not enough competition to stress any predator population,” said Chris Servheen, grizzly bear recovery coordinator for the U.S. Fish and Wildlife Service.

“In fact, a few years ago we had a big male adult grizzly that had great success following wolves and mountain lions around and stealing whatever they killed,” he said. “That bear stayed fat and happy and never did have to hibernate.”

In Yellowstone, experts predict that most wolves eventually will settle near their release sites in the north-central portion of the park, because that is where most prey animals live. But only a successful restoration effort, coupled with the cooperation of neighboring state officials, will determine the wolves’ ultimate range.

Before they were vanquished by government-backed poison and trapping campaigns in the 19th and 20th centuries, wolves thrived in nearly every region of North America north of Mexico City.

Once numbering in the millions, only about 2,000 wolves are left in the Lower 48 and about 7,000 in Alaska, according to game officials. Their absence disrupted the natural balance of predator and prey throughout the Rocky Mountain region and resulted in a population explosion of deer and elk.

Many biologists expect the Fish and Wildlife Service’s wolf recovery project here, which is based on years of consultation with scientists and 160,000 public comments, to be successful because of the abundance of game and Yellowstone’s status as a remnant of America’s wild frontier.

The goal is to create a breeding population of 100 wolves here and in Idaho within five years, and then remove wolves from the endangered species list.

A small number of the resilient, intelligent beasts are beginning to wander into the northern Rockies on their own, raising concerns among ranchers who regard them as marauding killing machines.

But without the historic wolf project, there were no guarantees that wolves would find their way here and establish breeding packs anytime soon.

Yet even some environmentalists complain about the costs and time spent on launching the restoration effort, which is siphoning off a great deal of federal resources. As a result, some say, other recovery efforts--such as one to save North America’s most endangered mammal, the black-footed ferret--are begging for private donations.

In the meantime, wolf foes, including the American Farm Bureau, are trying to halt the reintroduction in court on grounds that wolves threaten sheep and cattle near both release sites.

Wolves do kill livestock. When they do, the recovery effort provisions allow that they be removed or killed and that ranchers be compensated for any losses.

Separately, the Sierra Club, the Audubon Society and other environmental groups are fighting aspects of the program in Idaho, where wolves are re-establishing themselves on their own. The problem there is that a compromise with local ranchers removed protections against harming any wolf in the region, introduced or not.

Those legal battles are expected to be decided in federal court later this year. If ranchers prevail, federal authorities may be ordered to round up the wolves and ship them back to Canada.

Working on an oat feeder on a grassy hill in the middle of his elk ranch near here, 87-year-old Welch Brogan sided with those who believe that wolves have no place in this region.

“The park thinks wolves are a great thing, but you get out in the little villages in the boondocks, and you’ll hear a different story about wolves,” Brogan said. “I asked one rancher what he’d do if a wolf gets a hold of one of his livestock, and he said he’d shoot the SOB.”

Given the uncertainties of the current political climate in Washington, Mike Phillips, who heads Yellowstone’s wolf project, is more worried about having support for the project cut out from under him.

“If these 14 wolves are the only ones we plant in Yellowstone, the project probably won’t work,” Phillips said.

“People have to understand that we are not producing a product here, like a book or a painting--the Mona Lisa doesn’t breed puppies or kill things,” he said. “This is a living, breathing organism that, if we are successful, will enrich the ecological fabric here and persist long after we’re gone.”