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Latest Studies On Yellowstone National Park's Wolf Packs Shows Stable Population


Latest research on Yellowstone National Park's wolf packs shows that the largest packs, and some of the largest wolves, roam the interior of the 2.2-million park. Photos courtesy of Doug Smith, Yellowstone Wolf Project director.

Editor's note: Contributing writer Beth Pratt recently caught up with Douglas Smith, who has been studying wolves for more than 30 years and who currently leads the wolf project in Yellowstone National Park. He is the co-author of Decade of the Wolf, a book that details the historic wolf restoration in Yellowstone. The two talked about the current status of wolves in the park and their impact on elk populations

You are the middle of your annual winter research—what are you finding initially?

The wolf population is pretty stable compared to last year. We had 94 wolves in the northern range in 2007, but now we have 38.  We saw a big drop for the two consecutive years prior, but essentially no change in the population this year.

Do you think the population has stabilized?

To a degree, and I guess the message from this trend is “less is more.” The wolves for many years overshot the capacity of the ecosystem, and now we are seeing a balance—a balance of all parts not just wolves. When wolves weren’t in Yellowstone the system was out of whack because there were tons of elk and tons of coyotes and other things suffered as a result. Now there’s greater balance among both plant and animal species.

I imagine this is more what Yellowstone was like before it got changed because of European humans. From research we know when you have a full suite of carnivores, you have lower densities of the main prey species, but you also have really resplendent and luxurious vegetation. Because without predators the herbivores are mowing it all down. In the lower 48 we eradicated wolves before we knew what they did, so we have these erupting game populations that exceed what a healthy ecosystem can sustain.

Many have been critical of the wolves for reducing the elk population and don’t see a decrease in elk as a positive development.

It’s incredibly painful dealing with people who don’t like wolves and say they have devastated the elk herd. And it’s difficult to talk to people who just want Yellowstone to be an elk farm. Yes, with carnivores you have fewer animals to hunt. But this is the way it was in Yellowstone before we interfered and we need to know what it was really like and be honest about it. I’m not saying I am in favor of predators being everywhere, but what’s happening here is a system being restored to balance.

When we start killing predators because we want more animals to hunt, it becomes agriculture. It’s like spraying weeds. Is that what we want the forests and the landscapes of the West to be, a big farming operation? An author I read recently said when wolves go, wilderness goes and I agree. I don’t want the world to be so highly manipulated that we have no place where wild nature can just be.

I hunted elk for four days this year and I didn’t get one and I am not disappointed. So I had four great days in the wilderness hunting and I did not take a shot. And I will do it again next year and if I don’t get one I am okay with that. I don’t live on elk. It’s a recreational pursuit. I don’t need to kill an elk to feed my family and I would say there are very few people who do.

Do you think wolves are the only reason the elk herd in Yellowstone has decreased?

Elk have come down for many reasons, wolves being just one of them. Yellowstone is a multi-carnivore system, one of the most beautiful and rich in North America. You go to Alaska and northern Canada you don’t have the carnivore richness you have here in the park with cougars and bears. Cougars have a higher per capita kill rate than wolves, and bears take a ton of calves. Also contributing toward the decline is that the state was managing for fewer elk. They were shooting cows like there was no tomorrow.
The third reason for the decrease that’s a harder thing to put our finger on is climate change. I think climate change makes elk more vulnerable to wolf attack.

Can you expand on this—the connection between climate change and elk predation by wolves?

The best answer to this question—it’s all changing here because of climate. The landscape is changing and it’s affecting elk and wolves are responding.

This is evolving research, but there is an interesting study going on east of the park by a graduate student at the University of Wyoming. We’re looking at the same trends, but we’re a little bit behind him. What we are both finding is that the annual “green-up” [when snowmelt gives way to vegetation] is starting earlier and it’s also burning up the mountainside a lot quicker.

The link to elk is this—when new vegetation is growing it’s the most nutritious for elk. At the start of spring elk are existing on fumes. To restore their fat they need quality vegetation for a sustained period. In the past the green-up would extend until August and the elk had a lengthy period to restore their condition. Now that time period is being reduced by up to 40 percent.

Winter is just tough for an elk. I sometimes wonder why evolution made it so tough—it’s bizarre. Elk head into winter with a fat content that will vary from 10 to 20 percent. If it’s less than 10 percent they can’t even conceive a pregnancy and they probably are not going to make it through the winter. If they are at 20 percent they will probably burn through all of that fat during a long winter like this one. They are eating, but it’s maintenance eating—to survive they are really relying on reduced activity and fat reserves. And if they have a calf on top of that, their energy reserves really get depleted, and it takes a long time to build back up.

So global warming is altering this green up, and they can’t recharge as well. Now this is all in the hazy phase of research, but what they are finding east of the park is the elk are adapting by not reproducing annually. Typically older elk would switch off, but 90 to 95 percent of younger elk in the past reproduced every year. Now we are seeing rates of only 60 percent of young migratory elk being pregnant.

Is there a difference in the findings with migratory versus non-migratory elk?

Non-migratory elk, which years ago did not exist, stay all year in alfalfa fields at low elevations. And they are doing great--they are booming. They can’t kill enough of them.

The elk that migrate into Yellowstone are not doing well at all. One reason is that they are exposed to a lot more predators in the summer, but the other factor is this relationship to changing vegetation. So you have to ask the ultimate question—why do elk migrate then? These elk migrated decades ago because it was a good thing to do and the green-up was working. But what used to work for elk and essentially was a really good strategy, isn’t anymore. And that to me is really disturbing. This strategy is hardwired in elk and they are still doing it and it’s failing them.

They may get a break this summer, as I think this is not going to be a year like I just described in the research, unless it turns hot soon. In 1996 and 1997 we had big snow years, but it turned hot and there was not a gradual letting out of the snow. Instead the Yellowstone River overnight was a chocolate, frothing mess, which isn’t normal either. 

If it lets out slowly this spring and summer, it will resemble the pattern we had decades ago. But the problem is next year is anyone’s guess -- we can’t rely on normal cycles anymore. This winter was the snowiest in decades, while last winter was anemic, all the snow came in April and May. It’s the unpredictability that’s the problem. We used to have an average with little blips here and there. Now it’s all across the board and animals can’t adapt.

What’s your opinion on listing the wolf as an endangered species?

I have this idea that being able to hunt wolves increases tolerance of them and lowers resentment. At the end of the day for me, that’s better than keeping wolves on the list when animosity towards them is high.

I think it’s fair to say we want to vigorously protect wolves in some places.  But I’m very much in favor—for a lack of a better way to talk about it— of zonal management. We can designate areas where we are not going to harvest wolves. And in other areas where wolves are clearly hard to live with because people are trying to make a living, you have some harvesting. This idea of social tolerance increasing by a regulated hunting season is where I think we need to go. It’s a very modern position, but I think we really need to be modern.

Any surprises in your research this year?

A really cool finding that we’ve discovered is that black wolves have longer survival times than grey wolves. For female wolves it’s double the life span. For a black female wolf the average age of death is 8, while for a grey female wolf the average age of death is 4. And we don’t have an explanation. When the results first came through I didn’t believe it and I made the guys who ran the survival analysis run it again. We’ve rerun it like three or four times now and with the same results.

What we think is happening is the gene is for black is tied to an immune function, so somehow black wolves have a higher survivability because they have a better immune system. Now the complicating factor is all of our black wolves except two—and we’ve genotyped over a hundred—are heterozygous black, not homozygous. Homozygous black—these guys are dying young. Heterozygous black have a survival advantage. Dan Steel is heading this work up as part of his doctorate study.

Is mange still a problem in the park?

It’s declined—it peaked two years ago. It may be something that just never goes away. We’ve handled a few wolves this year that don’t have bad mange but they have annoying cases of it.

Now that the Druids (wolf pack) are gone, who do you predict will be the next “rock star” pack?

The pack that is filling behind them is Lamar Canyon, but the biggest pack in the northern range now is Blacktail with 14 members at year-end. One trend with the wolf population decline is that pack sizes have dropped across the board, except Blacktail and Mollie’s, and Mollie’s probably hasn’t dropped because they are bison killers.

Blacktail will probably be the dominate pack in terms of size, but what gets you stardom and fame is visibility and that happens in Lamar Valley and Slough Creek—and the pack in that area is Lamar Canyon. And what also gets you stardom and fame is having charismatic individuals. And Lamar Canyon does have one with their alpha female—06 is her nickname, but she’s not collared.  She’s a very smart wolf, very atypical, and a big hunter. Males usually have a lot to do with the hunt—she does it all. To the wolf-watching community she is starting to be their rock star.

What are some other trends you have found in your observations this year?

I talked about the population decline, but it’s been mainly with the northern range packs. In the interior of Yellowstone, the number of packs have been largely stable. I think that’s because for the northern packs it’s primarily a wolf-elk system, while in the interior, it’s a wolf-elk-bison system. They subsidize their diet with bison, which I think is pretty important as that population has not declined as precipitously as the northern range.

Last year we spoke about 495M—the alpha male of Mollie’s pack—a pack that regularly takes down bison. Is he still the largest wolf ever recorded in Yellowstone?

495M is a pro. He’s doing great. We think he’ll turn 7/8 in April, so he’s past his prime, but he’s still hunting bison. That is what is interesting about wolves—there is no such thing as a generic wolf. They are best at killing between 2-4, but if you have to keep killing and there’s no-one to help you, you just do it. I am skiing into Pelican Valley later this month and we’ll watch him for several days.

But there is a new big guy--760M in the Delta Pack. The last time we caught 495 he had meat in his stomach and weighed 143 pounds. When we weighed 760, he had a truly empty stomach, which I know because the effects of the drug cause them to vomit sometimes, and he was puking bile. So he weighed 147 pounds with nothing in his stomach.

I’ve been studying wolves for 32 years, and 760 was a sight to behold. I’ve handled hundreds of wolves, yet I thought he was a wonder of nature. And then I just started thinking in my head as I looked at him, he lives in the most remote area of the lower 48, and this is the kind of wolf that remoteness produces.

As a scientist you take the viewpoint that you can find answers. And for the first time I thought this is a wolf that truly has secrets. This is the Lower 48, it’s not northern Canada, it’s not Alaska, and we have a modicum of wildness here. He was something—not just another wolf. And it sort of reinvigorated my fight and restored that mystique of the wilderness for me. We have to redouble our efforts to save wildness.

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The elk population is coming to an end because of wolves? It's called circle of life as others have stated when elk population goes down so does the wolf. When the elk population increases so does the wolves.. How hard is it to understand that!!

and to the ... last comment.. wolves dont just kill the elk and eat unborn calf wasting and letting meat rot away, they tend to eat everything if they can't finish it they come back to it, it also leaves meat for the scavengers such as coyotes, birds, foxes, bears, etc... just cause the elk population is going down doesnt mean shit it means things are leveling themselves out as they should its called an ecosystem try reading more and being better educated... Wolves were apart of yellowstone area long ago as they were in other states before man killed them of due to the big bad wolf theory..

Also get over yourselves saying man could of better controlled elk populations by hunting them and not decreasing them as much as wolves.. all you people care about is the hunting or trophy hunting! and I'm not against hunting what so ever. The fact is the wolf was hunted to near extinction. There now being brought back and the ecosystem is balancing itself out...

Heres an ex. the grand canyon used be a very lively lush environment and "sporting hunters" wanted to have more deer to hunt. so they killed off the wolves and other predators in the area which in turn increased the deer population dramatically! the deer ate all vegation in area and killed itself off or moved on to greener pastures, and forming the climate and ecosystem its currently at now.

So how is reintroducing a natural predator to an area where they were killed of because of humans a bad idea? Again its called an eco system people! get over yourselves already! the elk wont disappear completey cause of wolves being reintroduced, nature has a way of balancing itself out! so think before you spit out stupidity.. The reason bison nearly went extinct was due to european settlers killing them off to disperse indian tribes else where to take their land due to the fact that was their main food source.. It wasnt due to wolves now was it? in fact after they killed off all the bison they went after the wolves as well.

Get over yourselves and stop saying oh well wolves are bad... we should be farming the elks in yellowstone so theres a bigger population to hunt for sport.. Yellowstone is not a farming operation for hunters! its to preserve the natural ecosystem that man has destroyed elsewhere that you can no longer see! with population increases rapidly increasing of people how long do you think it will be before theres no natural environment or animals? it's already happened elsewhere! easter island was one them.. sounds to me like population of people needs to be better managed. not the other way around. How long before theres not much of anything left? you really want that happen?

Nature has taken care of itself just fine before we came along.. Its called an ecosystem! wolves and elks being a part of that they will balance one another out time and time again. They are not an Invasive species! we killed them off and their being reintroduced thats not invasive people! nature and the ecosystem will balance things out long after we're gone as well. Try reading the book collapse and how the effects of people killing everything off has.. including its own people. such as easter island as I stated..

Editor's note: This comment was lightly edited to remove some gratuitous language.

There is no such thing as a "Rocky Mountain Timber Wolf." It's a myth. The Canadian wolves reintroduced into Yellowstone in the early 90's are genetically identical to the Grey Wolves that lived there historically.

The "Rocky Mountain Timber Wolf" is a myth created by wolf haters. This myth may have come about from wolf/dog hybrids that existed after the demise of the Grey Wolf in the park. That's not a genetically pure wolf, just the straggling remains of what once lived in the park. Either they actually believe in a false species called the "Rocky Mountain Timber Wolf" or it's just an outright lie from folks who are having a more difficult time finding trophy elk to shoot for themselves or their rich clients. The trophy bulls aren't just wandering around waiting to be shot like they used to when there were no wolves in the area. A balance will return if the historic predators are allowed to do their thing. In areas with wolves, the days of the "canned" elk hunt are over, and rightly so.

Wolves prey on everything they kill and don't even eat the elk. They kill a pregnant elk and while she is still alive they rip open her uterus and eat her unborn calf. They leave the mother to rot. They kill the strong also ripping them apart.

Typical waste of a resource and massive waste of taxpayer dollars. The wolf is and will prove to be a collasal mistake costing the states of mt, I'd, wy, millions if not billions of lost revenue.

The Yellowstone elk herd could have been managed by sportsmen and it would have cost the taxpayer nothing instead the Feds came in and introduced a invasive species and pushed the states aside. There numbers swelled way past the management numbers and the states had to waste more tax dollars to try and contain the disaster. Finaly the states won in court to have a season. However hunting cannot possibly contain the wolf. So more wasted tax dollars to shot them from helicopters, trap them etc etc.

The wolf can do well and there can be a balance in a massive ecosystem where there are not people and agricultural boundaries confinement for both the elk and the wolf. When u turn them lose in a big zoo with no fences. Yellowstone is that it's not Alaska its not the far reaches of Canada. Things get messy and the once largest elk herd is reduced to nothing..

First off, wolves aren't the only animals they prey on elk calves. BEARS prey on elk calves more than wolves, even. Climatic change, too, has effected whether they're even born! Global warming does have an effect, maybe not as big but just as significant.

Second, reread what you just said. Even if elk calf survival is in the ones, the most members of herd are the young ones, elk born at a max of two to four years before--so they're doing fine.

Third, its technically impossible for all of the elk from Yellowstone to be gone, especially solely at the hands of wolves. And not just Yellowstone and wolves and elk, but everywhere and every predator and their food source. Ever heard of balance? More so, heard of "survival of the fittest"? Let's use the wolf-elk example.

When the elk population is low, the wolves are likely unable to bring down the healthiest, biggest, smartest, etc. elk. Which, after a high-time for hunting, is pretty much the characteristics for the whole herd in such a situation. Wolves starve. They die. A chance for elk population growth. More elk. More sick, injured, old etc. elk. More chances. Wolves prey upon the weak. Wolf pop. booms. More wolves eqauls more food needed equals more hunting. More hunting equals low elk pop. but with healthy elk. Wolves starve. They die. And so on. (In a singing voice: "It's the circle of life!")

I couldn't agree more.

1. To those who like moose: Scientists have recorded less than 2 moose killed by wolves per year. More than 25 moose are killed by cars per year. There are at least 3 recorded moose kills from poaching(probably much more unrecorded) in the park each year. Seems to me like cars should be taken out of the park because they are more of a problem....
2. To those who complain about Rocky Mountain Timber wolves being the native species: The Rocky Mountain Timber wolves and the Canadian grey wolves are the SAME SPECIES. They are both Grey Wolves (Canis lupus), look it up if you don't believe me. Just look at their scientific name: Northern Rocky Mountain wolf(Canis lupus irremotus). They are both subspecies of grey wolves (Canadian grey wolf being a general term used to describe any of the various subspecies of grey wolves living in Canada) which have intermixed with all other subspecies of grey wolves in North America for thousands of years. Rocky mountain wolves share some Canadian wolf blood and vis versa.

 The relationship between wolves and moose on Ilse Royale NationalPark has been continuously studied for over fifty years, and continues today.  I think all you wolf haters should also do some studying.  A good place to start would be reading the Isle Royale Wolf/Moose annual reports published on line every year.  Some of the above comments are truely hilarious!

Has anyone yet made the connection that a reduced Elk herd will mean eventually, reduced wolf numbers. They go through stages as they do on Isle Royale. When there is plenty of prey, you get plenty of wolves. When prey numbers drop, the wolf population will drop shortly thereafter from lack of food (low pup survival rate). When the wolf numbers are down, prey numbers increase. And so forth...and so on.

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