AP

YELLOWSTONE NATIONAL PARK - Hunters and outfitters blamed wolves when they began seeing fewer elk in areas near the park in the decade after gray wolves returned. But some researchers say drought and even years of great hunting played an important role, too, and the wolves themselves seem to be paying a price.

"To a degree, people are crying wolf way too soon," said Yellowstone wolf biologist Doug Smith.

Smith and others concede that wolves have contributed to declining elk numbers near Yellowstone, particularly in the northern range herd that migrates into Montana in winter. But there is intense debate over how great their role has been - and whether it has been necessarily bad.

To outfitters like James Hubbard, the wolves' effect has been huge, and they point to the case of the northern range herd - for years, a rich source of winter hunting near Gardiner, Mont. - to make their point. The herd, as recently as 1994, had 19,000 elk. The most recent count last month put the population at only 9,545.

That's not just coincidence, Hubbard said: Wolves, reintroduced to the region in 1995, are "killing the industry."

"Hunters come out and don't see near the elk," the Gardiner-area rancher and outfitter said. "They used to see so many it was unreal."

But J. Christopher Haney, a senior conservation scientist for Defenders of Wildlife, said wolves are being made a scapegoat. Elk numbers in parts of the West, including the northern range herd, were very high for a number of years, he said, but much of the area has also experienced extended drought, which can further stress range conditions.

"Hunters have had it good for a long time," he said. "When you have these high numbers, it gets in people's heads, 'This is natural, this is what it should be,' when nature is always changing," he said.

The population of the herd grew dramatically after federal officials stopped trying to regulate elk numbers in the park in the 1960s.

Elk leaving the park have been hunted in Montana since the 1970s. But Kurt Alt, a state wildlife manager, said that since 2000, the population has steadily declined. He said there is concern whether the population can sustain itself with the number of calves - among the more vulnerable animals in the herd - withstanding predators, including bears and wolves, to survive a year.

Hunting permits in the area have been scaled back to see if that might help stabilize the elk population, he said.

But Alt said he believes the weight of evidence has shown adding wolves to the mix has been the "major factor" in the herd's decline. Before the federal wolf reintroduction in and around Yellowstone in 1995, he said the herd was able to maintain relatively high numbers and rebound fairly quickly from natural events, such as major fires or drought.

"One thing that has changed is the addition of wolves to the system," Alt said. "We're seeing a decline in the population with the addition of that extra mouth."

Ed Bangs, a federal wolf manager, said wolves, mountain lions and other predators may speed up declines in game populations caused by other factors, such as hunting, changes in habitat conditions and harsh weather. When elk populations are at such highs, there's "no way to sustain that, and when numbers go down, people are always looking for something to blame," he said.

"You hear, 'Wolves are killing off all the elk,' and none of that's true. Some people say they're not having an effect, and that's not true, either," he said, adding: "What wolves do is cut out the highs and lows."

Skinnier wolves

There are places in the three-state region where wolves are present and elk populations are thriving. A key difference between those and Yellowstone is wolf densities, Smith said.

The density drops sharply at Gardiner, near the park's northern boundary. Wolves outside the park that get into trouble, say for killing livestock, can themselves be killed.

But there's new evidence suggesting wolf numbers inside the park may now be leveling off, or even declining, he said.

Smith, who has been studying the wolves here since their return, said that in the past four years, as the number of northern range elk has declined, there has been more fighting among packs for food, scrawnier wolves and indication their numbers may have peaked, at 174 wolves.

That does not mean wolves are eating themselves out of house and home, though, Smith said. Instead, he believes wolves and other predators have helped thin out the weaker, more vulnerable elk, leaving a smaller population of stronger, healthier animals.

Because wolves tend to pick off prey least likely to put up a big fight, they're having to work harder for a meal - some, like the Mollie's pack, are taking on burly bison in late winter - or go hungry, Smith said.

In the past five years, he said, wolves in the park have eaten fewer elk in late winter than before.

"I have seen wolves starve when there's adequate numbers of prey out there," he said.

Some wolves now are in poor condition. Wolves overall are lighter than they used to be, and fighting has picked up between packs competing for carcasses, leading to far more dead wolves a year now than in the first years after reintroduction, he said.

Last year in Yellowstone, wolf numbers declined for only the second time since reintroduction, to 171 animals. In another decade or so, Smith guesses there could be half the wolves there are now.

The big question is: How will wolves contend with declining elk numbers? Either wolf numbers will fall off, too, or wolves will augment their diets with bison, which is in ample supply in Yellowstone but difficult for wolves to kill, Smith said. He has known wolves to be gored and even killed trying to take down bison.

"It will be exciting to see what happens," he said. "It will affect not only the wolves but the elk."