BILLINGS, Mont. — An acclaimed elk herd in Yellowstone National Park took a major hit last year, with biologists saying almost one in four of the animals were lost, mainly to predators and hunters.
As recently as 1994, the northern Yellowstone elk herd was the largest in North America with almost 20,000 animals that migrated between the park and parts of southern Montana.
But those numbers have plummeted sharply since wolves were reintroduced 15 years ago, adding to threats that already included mountain lions and grizzly bears.
Figures released Wednesday showed the Yellowstone herd down to a minimum of 4,635 elk. That's a 24 percent drop from last winter, and wildlife officials said the decline was unexpected because the herd in recent years showed signs of stabilizing.
"Either we counted them poorly this year, predator effects were stronger, the big snow event made us miss more elk, or more elk were harvested," said Park Service biologist Doug Smith. "Usually the best answer in ecology is all of the above."
He said there was no reason to suspect a continued decline, and that a smaller herd is healthier in some ways because it gives the animals room to thrive.
Bill Hoppe, an outfitter near Gardiner, said harsh weather in the park in late November pushed many of the animals to lower elevations in Montana. He estimated several hundred bull elk from the herd were killed by hunters in the last part of the season – one of the most successful harvests in years.
Yet in the 1990s, several thousand elk were killed in some years. Hoppe believes the herd's best days are gone, and a local hunting industry that already was ailing will collapse.
"There's coyotes and there's wolves and there's bears and there's mountain lions. (The elk) may come back, but it's going to be slow," said Hoppe, who is also president of a group called the Friends of the Northern Yellowstone Elk Herd.
The Park Service has no set population target for the herd, but the latest count falls below those of Montana Fish Wildlife and Parks.
The state's elk management plan calls for 3,000 to 5,000 elk in parts of Montana just north of the park, said Fish, Wildlife and Parks spokesman Ron Aasheim. This year's count included 2,236 outside the park.
Aasheim said state officials would review whether hunting restrictions need to be tightened in future years to help bolster the herd. Yet it's uncertain how much could be done. Harvest limits for reproducing female elk were down to just a few dozen north of the park this year, versus almost 3,000 a season at their peak.
Park biologist Smith said the long-term decline was indisputable, with 70 percent of the herd gone since wolves were reintroduced to the park from Canada in 1995.
Conservationists credit wolves with helping restore balance to the ecosystem, in part by reducing the size of a herd some had said was far too large at its peak.
Smith declined to weigh in, saying that was before his time at Yellowstone. But he pointed out controversy has long followed the northern Yellowstone herd.
"Yellowstone is one of the most predator rich environments in North America and that has an effect on elk," he said. "But the biggest criticism when I got here in 1994 was there were too many elk. Now we're getting criticism there's too few elk. The Park Service does not specifically target a population size."