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Annual Count Shows Huge Decline In Yellowstone National Park Elk Herd, But How Accurate Is It?


Has there really been a 24 percent decline in the northern elk herd at Yellowstone? Wildlife biologists aren't so sure. NPS file photo of elk wintering in the Lamar Valley.

Nearly one-quarter of the northern elk herd at Yellowstone National Park is missing, according to the annual winter count, but biologists aren't sure if there's been a stunning decline in the herd or if other factors have skewed the tally.

During an aerial survey in late December biologists counted 4,635 elk, a 24 percent decline from the 6,070 animals counted a year earlier. While the one-year decline seems dramatic, Doug Smith, Yellowstone's wolf project leader, said a number of factors lead him to question "how good this count is."

Heavy snows in November and December could have pushed many elk out of the park, he said, and the aerial tally, which normally has an error rate anywhere from 10 percent to 50 percent, could have been significantly off.

Elk are among the iconic animals that Yellowstone tourists expect to see during vacations to the park. The northern herd -- one of the park's seven elk herds -- is particularly photogenic, with small bands milling around park headquarters at Mammoth Hot Springs and larger numbers readily seen in the rolling grasslands that rim the park road that winds from Mammoth Hot Springs to Cooke City just beyond the park's northeastern entrance.

When Yellowstone officials ceased artificially capping the herd at roughly 3,000-4,000 animals back in 1967, there was a population explosion that saw the northern herd expand to nearly 20,000 animals, Dr. Smith noted Wednesday during a telephone conversation.

That number steadily has been coming down through the last decade or so, in part due to more predators in the park than in past decades. Wolves were returned to Yellowstone beginning in 1995 to restore the park's full complement of predators, and mountain lions also found their way back on their own. Those two predators, along with ever-opportunistic grizzly bears, have helped tamp down the elk numbers, the wildlife biologist said.

Hunting in Montana just beyond the northern range also plays a role in population control. (Come winter, as many as half of the elk in the northern herd head to lower ground; in this case, Montana, according to park officials.)

Dr. Smith can't accept that predation alone has cut nearly a quarter of the northern herd, especially not when the park's wolf population is ebbing due to disease. In the park's northern range just 37 resident wolves were counted last year, according to park officials.

"Is predation a factor? Absolutely, a huge one. But we can't weight it," he said. "The feedback is that it's all wolves, and that's not the case."

Heavy snows in late November and early December "could have changed the elk distribution entirely. And about half the time we do the count in January or February. So we have an unusual snow amount, and the timing is different."

Yet another factor is the hunting season in Montana.

"This unusual snow event pushed a lot of elk out of the park, and they had a really good hunting season, said Dr. Smith.

Another factor that could be in play is climate change. A drier Yellowstone means less forage for elk, which means cows head into the rut with less fat reserves to help them through both winter and their pregnancies. As a result, reproduction can fall. While this past fall and early winter was wet, the trend during the past 15 years has been drought, according to the wildlife biologist.

At the Montana Department of Fish, Wildlife, & Parks, Livingston-based wildlife biologist Karen Loveless agreed the early snow did push elk out of the park and into Montana. But she couldn't say large numbers of Yellowstone elk made the migration.

"We had early heavy snowfall. That occurred toward the end of the general season. In the early hunting season we had light harvest, then the last 10 days, two weeks we did have substantial bull harvest," Ms. Loveless said, adding, though, that "I honestly doubt that the harvest that we had down there could account for the drop in the numbers.”

The Montana biologist also said that during her flights over the hunting districts just north of Yellowstone she didn't notice an inordinate number of elk moving out of the park. If there was a big movement, she had no idea where they might have gone to be out of sight.

“Obviously, it’s deep snow and it's mountainous and there’s not another winter range that I think they would move to," said Ms. Loveless.

“The only possibility is if they continued further north up the Paradise Valley," she said, only to add that, "I've been flying over that and haven’t seen a substantial number of elk up there.”

According to a park news release, there has been about a 70 percent drop in the herd's size since 1995, when there were 16,791 elk counted. That was the same year the wolf recovery program came to Yellowstone.

"Predation by wolves and grizzly bears is cited as the major reason for the decline in elk numbers," the release noted. "Wolves in northern Yellowstone prey primarily on elk. Also, predation on newborn elk calves by grizzly bears may limit the elk population’s ability to recover from these losses."

When asked why Yellowstone officials opted to put out a news release describing a 24 percent decline in the northern herd when the tally was in question, Dr. Smith was quick to answer.

"Transparency. Honesty. Many people think we're lying and trying to do a cover-up to hide the effects of wolves, so the only way to dispel those myths is full disclosure of what you get," he said.

While park officials are debating whether to do another count this winter, Dr. Smith said there's one positive if the decline noted in December proves true.

"If there's a silver lining here, it's a smaller, healthier elk herd," he pointed out.

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The problem is wolves...period.

Well that, and pro-wolf biologists like Doug Smith who use smoke and mirrors to try hiding the truth.


Thirty-seven wolves killed 1,400 elk?

Don't understand the problem Dr. Smith has with predation being one of the primary causes in the decline of the northern elk herd. To blame it on "climate change" is an absolute joke. Must be a joke. Ha ha, very funny. Or maybe I have it skewed.... Is it possible that there areas in Wyoming, Idaho and Montana that ARE NOT, for whatever reason, subject to the whims of "climate change"??? It must be so, as there are areas within those states, where the elk herds are increasing, cow/calf ratios are up, and pregnancies are present in almost 100% of cows. How can this be? I can drive for an hour, and go from the "climate change" of Montana, affecting the northern elk herd, and be in the Bighorn mountains of Wyoming, where the elk are prospering? How can "climate change" and drought be so different, considering these zones are so close together on the map? I point out the coincidence that wolves are present in the one area (northern elk herd) and are not present in the other (Bighorn Mts.). Of course, applying common sense does not further Smith's cause of more and more wolves everywhere philosophy... VW

From the USFS website:
Elk are primary prey for wolves - 92% elk of kills during winter

average kill rate per wolf per month = 3.05 elk
3.05 x 37 wolves = 112.85 elk killed per month
113 (rounded up) X 12 months = 1354 elk killed by wolves a year....pretty simple math

Anonymous, if you could provide a link to that page, it'd be great. A quick scan couldn't bring it up.

As for your math, that would depend on all 37 wolves being healthy adults, no, and entirely focused on elk for food?

Here are a few more snippets from the USFWS page on wolves:

Do wolves really take the old, young, sick, starving, or injured animals?

It is well-documented that wolves tend to do this. Hunting and bringing down big game is dangerous work and wolves are sometimes killed by elk, moose, and even deer. In the wild, they cannot afford to be injured; therefore, they go after the safest animals to kill and often leave strong animals alone. A recent study of wolf predation on elk in Yellowstone National Park, for example, found that wolves tend to kill calves and older animals – adult elk killed by wolves were about 7 years older than elk killed by hunters. If weather or other conditions make prey unusually vulnerable, wolves can and do kill prime-aged animals but wolf predation tends to be selective.

If wolf numbers get too high will deer and elk be eliminated?

No, wolves have lived with their prey for many thousands of years and the health of wolf populations is dependent on the health of their prey base. Under certain conditions wolves can cause local decreases in prey numbers. But if deer and elk numbers were to decline over an extended period of time, due to severe winter conditions or habitat changes, wolves would have less food available and their health would decline. They would then produce fewer pups and fewer pups would survive to adulthood. Also, more adult wolves would die because of poor health or in conflicts with other wolves. Thus, wolf numbers would decline before their prey could be eliminated.

Do wolves kill more than they can eat?

Sometimes, but rarely. The few times that wolves have been documented killing more than they could eat were when conditions such as deep snow or other unusual circumstances made it easy for them to kill their prey. Even then, they returned to those kills and continued to use them.

Against this background, it would seem that if indeed the 37 wolves alone were responsible for the 1,400 elk that seemingly vanished between December 2009 and December 2010 that the prey-predator balance was being brought more in line.

Hell yes 32 wolves can kill 1,400 elk! Have you ever researched how wolves kill..? How many ungulates they kill, not just for food, but, also for sport and teaching.
It is estimated that each wolf kills an ungulate for food every two weeks, and, for each one they kill for food there is another taken down for the sport/teaching.
Have u ever seen wolf kills and noticed that there is generally very little actually eaten of the animal?
Wolves ARE a major problem! Maybe some of the elk didn't want to go back to that winter range and get picked off like appetizers on a plate so they went elsewhere!?

How is it the wolf lovers don't realize the a wolf doesn't actually have to bleed out an elk to kill it. They starve them to death in whole herds in the back canyons or run them to exhaustion in the deep snow causing them to die from the elements.
It's a sad thing that we have let this issue get so far out of control!
What ever happened to original planned numbers of 300 wolves and now the damn people aren't happy with 3,000..!!!?

A study recently has shown that fewer elk cows are even pregnant in wolf populated areas. They are run and spooked to the point that they don't have the nutrition necessary to carry a pregnancy. In nature, the female is most important, keeping her alive comes first, so nutritional intake, whatever it may be, will go to maintain the life of the cow. The fetus or embryo will be reabsorbed. The age of the cow elk in these wolf predated herds are getting older and older. There are few recruits to take their place. Within the next 5-6 years, the elk herds will likely reduce again by another 75% or so. That leaves buffalo, antelope (fawns), deer, and bighorn sheep. There are no moose left, or at least not enough to be counted as a potential prey species after elk disappear. So.... the deer, antelope, and sheep will be next, with those wolves numerous (within a pack) and large enough, with buffalo for prey. Forget the rabbits, they are already gone. Starving wolves will go to catching voles, mice, rats, and any thing else available to stay alive. Packs left will increasingly go after grizzly bears, sows with 2 or more COY in particular. The coyote and fox will be gone. Only a few wolves left which are able to kill bison, and other wolves. Spring time will be fairly easy for wolves, where the buffalo calve, as calves are easy prey, once the predator figures it out. We watched 3 wolves in the Lamar valley kill a newly born buffalo calf very easily. She had moved away from the herd to calve. The wolves apparently were experienced, and knew what was going on. They were in and grabbed that calf practically before it came out, while the cow was still down. They obviously did enough damage to the calf to kill it, or make it unable to ever get up to nurse. Not being dumb, the wolves then left, and harassed the cow from a distance. She licked her calf, pawed it, chased wolves, and eventually figured out that the calf was dead and she walked away back to the herd. This took about 4 hours. The wolves then came in and took the calf. End of story. When the time comes, and buffalo are the only choice, the buffalo herd will start to age out, due to lack of replacement, and the ranchers will no longer have to worry about the buffalo leaving the park and infecting their domestic cattle with brucellosis. There will be fewer wolves in yellowstone, and virtually little other viewable animals. Wolves, not being stupid, will leave the park and search out areas of more abundant prey. They will continue to cut prey numbers down, and turn to livestock, pets, and perhaps even people. The mule deer herds of Montana, Idaho and Wyoming will become virtually extinct. Mule deer are already on a long slide downward, with their population decreasing everywhere. The prey animals that are left outside the park will move into and close to homes, settlements, towns, etc., and will increase likely hood of wolf/human conflicts, as the wolves of course, will follow them. Time to move all the humans to the big cities, or to designated living areas. Will be interesting to see what really will happen..... VW

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