"Truthiness" Only Gets You So Far

Wolf packThe topic of predators in general, and wolves in particular, conjures much emotion on both sides; one need look no further than the comments posted on various articles in this blog to see how hot people’s blood runs. Look closer at these comments, however, and you’ll notice that where the emotion runs particularly high, the credibility of the statements made often runs particularly low.

Notably, the subject of wolf restoration seems to draw the same tired old assertion that wolves are wiping out their prey. A bit of horse-sense would lead most to the conclusion that if wolves were prone to eat themselves out of house-and-home that they’d have gone extinct long ago. But we strive to go beyond horse sense here. To the largest extent possible, we aim to back-up our assertions with peer-reviewed science. So, in that spirit, I present below a refutation of one such bit of wolf folklore. More importantly, I will edit individual comments to this blog that continue to perpetuate wolf hysteria with links back to this and other posts that refute such myths.

Public dialog is important. Thoughtful, well informed dialog is even more important. So, consider this:

Question: Are wolves responsible (or primarily responsible) for the decline in the density of Yellowstone’s Northern Range elk herd?

Ongoing research in Yellowstone National Park indicates that the decline of Northern Range elk is multi-causal: climate effects due to drought, predation (wolves, bear and cougar), increased hunter harvest of female elk at the time of wolf reintroduction. At the time of wolf reintroduction, elk density was 13-15 elk per square kilometer on the Northern Range, a very high elk density. Now elk density is 6-7 elk per square kilometer, still very dense. Most areas outside Yellowstone National Park are below 1 elk per square kilometer. Therefore elk in Yellowstone National Park have declined from very dense to just dense. Data indicate that fewer elk is proving beneficial to other aspects of the system (vegetation, scavengers, bears, songbirds, etc).

Literature cited:

John A. Vucetich, Douglas W. Smith, Daniel R. Stahler. 2005. Influence of harvest, climate and wolf predation on Yellowstone elk, 1961-2004. Oikos. 111 (2), 259–270.

Roger J. Anderson and Alice Wondrak Biel. 2005. Ten Years of Yellowstone Wolves (1995-2005). Yellowstone Science. 13 (1). 2-45.

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25 responses to “"Truthiness" Only Gets You So Far

  1. “Again, Rob, go see for yourself, that is all I ask. All of the predictions they made on impact was based on a MAXIMUM of 300 wolves”

    “I understand that 300 are the MINIMUM the three states were supposed to have,”

    I AM SO CONFUSED!!!!!! If the wolves of Isle Royale have not eaten themselves into starvation in the sealed environment of an island what makes you think it will happen in yellowstone where elk and wolf can come and go out of the park as they please?

    I know you like me to provide references for my claims so here are a couple for you to gander at… I think they could really help our debate.

    http://dictionary.reference.com/browse/maximum
    http://dictionary.reference.com/browse/minimum

  2. The elk count is an estimate, and yes it is claimed that the reason we are not seeing them is because they are hiding. It surely cannot be easier for a herd of 20-30 grazing elk to hide than a pack of 10-20 wolves sliding thru the forest.
    It is very simple, when the wolves exceed the carrying capacity inside of Yellowstone they will do exactly what they are doing right now…leave. That is why they are out preying on livestock and wildlife outside of the park, there is not enough food for 1500 wolves inside of the park, and probably not even 175 long term.
    I understand that 300 are the minimum the three states were supposed to have, but we have exceeded that, does that mean it was actually only a talking point and no one intended to abide by that number? What number is enough for you guys, or is there a maximum, will you always want more and more?

  3. Marion,
    The number that you continue to prattle on about,300, is/was the MINUMUM acceptable number. You know this; has been pointed out to you; and can be found in any number of reference and internet searches. Why cant you at least try to be cognizant?

  4. i’ve got to say that a good debate needs every perspective, evreyone here has made valid points but the wolves will not exceed the carrying capacity without a substantial decrease in the own numbers as a result. It’s about the equilibrium that will be reached.

    Also, good point Steve. Elk may decrease by some amount but others wil benefit, that is nature.

  5. So the wolf counts are artificially low because of difficulty to count them. How do you know the elk count is not also artificially low because of difficulty to find them all? Seems like you pick and choose what to believe to fit your views… And you gloss over the damage done to biodiversity because of an overpopulation of elk. Just because you can’t see the damage caused by overgrazing doesnt mean it doesn’t exist.

  6. Again, Rob, go see for yourself, that is all I ask. All of the predictions they made on impact was based on a maximum of 300 wolves in the three states. There is 5 times that many wolves and one can be pretty sure they can’t count all of them. New packs show up almost every year. I guess it really does not matter, nothing can be done to change anything at this point in time.

  7. Come on, Marion! Why don’t you just come right out and say it: “The end is near! The end is near! Repent all ‘ye wolf huggers! The end is near!”

  8. By the way, the wolf count is up to 175, and those are jsut the ones they can see. At 2 elk per month per wolf do the math.

  9. You misunderstand Joe, I am well aware that there is nothing that can be done at this point in time about the over population of wolves in Yellowstone and the impact on other animals. My suggestion that you go to Yellowstone is not because anything can be changed, it can’t, but rather that you see first hand what damage has been done. Maybe next time wild suggestions to manipulate nature can be thought through a little better.
    They will continue to breed and feed until there is nothing left to eat and they will either: starve, kill each other off (won’t that be exciting for wolf watchers as they cheer their favorite pack?), or leave the park to find food elsewhere. then what are you going to watch? Wolfers will have to sit at their computers and blame ranchers for the fact the wolves have eaten themselves out of food.

  10. Sorry, we’re looking at a situation where the drought and rutting behaviour are blamed for poor sightings but that the better outlook is due to wolves being killed? Sounds like misplaced persecution of wildlife to me, is all too common. Killing a top predator often only maintains numbers anyway. Quite often what happens is that the amount killed merely leaves more space to fill the population from the next generation by reducing the competition for resources. It’s all to easy to see a wolf, look at it as a killer, point a gun and say problem solved. Nature just isn’t that simple.

  11. Thank you Joe. A voice of education and reason.

  12. You called me a liar about the 2007 March classification count that was supposed to be equivalent to the 2006 count of 3649, that is the only Yellowstone Northern herd I have seen above the teens. You forgot to provide a link that gives that info. I am aware that count was considered inadequate, but that is the ONLY count that I have seen. On June 30, 2006, Bangs specifically stated that no population count was done in March 2006. In January 2007, he stated that the 6788 was 150 more than the March 2006 count.
    The rest of the Wyoming numbers are very interesting in that the rangers claim the drought is why the elk numbers are so low in Yellowstone….except for one couple who told me the ranger said the reason the rut in Mammoth is so puny is because the bulls stay in the high mountains for the rut!
    I urge all of you to go to Yellowstone for the rut during the next 30 days, if you have ever been there for it before you will be shocked. Even the Madison has only 1 fair sized 6×6 and 1 7×7, maybe a total of 50 cows.
    I heard one family complaining to the clerk at Fishing Bridge that they had been told that Yellowstone has a lot of elk, but that they had not seen a single one. What could the poor clerk say except to keep looking. I suggested they try Mammoth.
    I came back early since the rut is so skimpy this year. What will next year or the following bring? I honestly do not know, but I have a hard time believing that 130 hungry wolves and a few hundred hungry griz and blacks area going to just sit and starve.
    One reason for the better outlook in the areas hit so hard by wolves in Wyoming is the aggressive killing by FWS. Remember Bangs, et al kill more wolves per year than were killed in the 42 years wolves were killed in Yellowstone.

  13. Elkhunter, you are correct that this process of reaching an equilibrium will take a certain amount of time but the growth pattern of a Wolf is usually follows a sigmoidal growth curve. This is a characteristic of a K-dominated species (not trying to confuse you with jargon here, stick it on google and you’ll see what I mean) that will grow slowly at first before a period of rapid growth, then slow as it nears the carrying capacity, K. These species are K-dominated because they reach this point and the population hovers around it with little of the boom and crash seen of the r-selected species. This is because once they reach K then they simply can’t exploit the resources at hand quickly enough to grow any further, resulting in a stable population of both prey and predator.

    The limits are numerous, but can be grouped as two main criteria. Firstly intraspecific competition, which is within the species, and can mean within the pack itself for part of the kill, or between competitive packs for territorial resources. This was a point made by Steve C, opposing packs will rarely tolerate each other and will more often than not drive the lesser group into less favourable areas that will support only a smaller population. If there is no territory issue, then wolves will travel to find available prey, but this represents an increase in hunting time that will again have an effect on the rate of growth.

    Again it is the rate at which wolves can actually predate that is often the limiting factor. The time taken to find the prey, then stalk, kill and eat it, while sharing the kill with the other pack members, that will put a limit on how fast the population can grow. I suggest some reading on wolf ecology for more specific figures on this, as it is far more detail than I can supply here.

    The other limit is interspecific competition, between wolves and other species, such as cougars, bears etc that may also prey on the vulnerable members of the elk population. Again, it’s all about the balance that is achieved by nature that our species seems to struggle to comprehend. The reason that all of these species manage to coexist is through the thousands of years of evolution and when one is removed in a short space of time, via hunting or habitat degradation, it is frequently detrimental to the ecosystem. Wolves for example; will often benefit wild birds and other mammals who will feed on the carcass, as well as the points I made in my previous post. Most importantly, I can think of no reason why such a magnificent and intelligent animal as the gray wolf shouldn’t be allowed to roam free on its home territory.

  14. Territoriality with other established wolf packs would probably prevent them from easily moving to more productive areas without them facing some mortality from other wolves…

  15. Joe, You make some very valid points, but I feel that balance would happen over the course of many years, not one or two. Also, would not the wolves just move to another more productive hunting grounds? I think instinct would push them in that direction. If food sources were low/more difficult to kill would they not just migrate to new territory? You probably have alot more experience with wolves than I do, but I do hunt coyotes alot and they follow rabbit and rodent populations closely. If we dont see alot of rabbits or rodents near hay fields, not very many coyotes. But in areas of high rabbit density, obviously more coyotes. And over the years it seems the area’s change. Have you encountered that as far as wolves migrating to new territory when hunting becomes more difficult? Or do they stay in their initial range’s?
    Elkhunter

  16. Very well written, joe. Thank you. I have a feeling that in the next decade we will start to see cyclical declines and increases in the yellowstone wolf population corresponding to increases and declines in the elk population.

  17. It is all to easy to criminalise someone for writing a comment as Marion has above. Whether you are a hunting lobbyist or an environmentalist then you have to accept that of course a predator will have the population of prey species. Wolves don’t know when to ‘stop eating’, they will predate the species, in this case Elk, until they reach a level that is sustainable by the population of prey. Once they reach this level, the predator population is effectively capped. There are a number of factors involved in this, but it is essentially density dependant. Basically, this means that as the population density increases more prey will be taken, but as the predator population increases the prey decreases to a point that the time taken to locate enought prey to sustain the predator population exceeds the requirements for growth. This does not mean a population crash by the prey on by any means, it represents an equilibrium between the predator and prey. Also of great importance is the target of the predator, usually young, diseased or old and frail. This will account for only a small part of the actual biomass of the elk population, and a small proportion of the productivity.

    For example, if the wolves did manage to annihilate the years young and all the old and frail members of the population, the extra time and effort needed to predate a healthy adult would far exced the demands of the population. The wolves would decline very rapidly, the elk would recover. Realistically, the wolves aren’t efficient enough to make this happen.

    What we need to understand is that the natural environment has been unbalanced by human actions. Top predators are vital to a balanced ecosytem. Although it is difficult for some to appreciate that an elf calf being killed by a pack of wolves is necessary, the effect of elk grazing in large numbers will be detrimental to a whole host of other species, from vegetation and invertebrates to other smaller grazers and their predators. It is often the case that a high biodiversity is maintained by a healthy keystone predator population, which limits an otherwise dominant population of prey species.

    I could go on, but I’ll finish here. I just read the articles and thought I could provide a little insight from an ecologists point of view.

  18. There are alot of different reasons for the elk situation in the Northern Herd, I dont think wolves are all to blame or are hunters all to blame. But the argument can be made that both effect the elk herd. In 20022005 calf recruitment was only 12-15 calves per 100 cows. VERY LOW. This year in 2006 calf recruitment was back to 22-24 calves per 100 cows. I have read the target is usually around 30 calves to 100 cows. In a study of 127 calves 72% were killed by predators. Bears, wolves, coyotes etc. In a different study of 150 calves 90% were killed during the first year, grizzlies and black bears being the main culprit, followed by wolves and coyotes. So its obvious that predators can have a large effect on populations IF calf recruitment is low. Here is the link to the info, scroll down to recruitment
    http://www.greateryellowstonescience.org/topic/elk/elkoverview.html

    My only point is if you continue to strive for greater and greater protections for bears and wolves, and not at some point controlling populations, you will at some point see an obvious impact in the elk populations.
    Elkhunter

  19. She was just being “truthy”. 🙂

  20. All of these cow/calf ratios over 20… was marion lying to us?

  21. Two excellent examples of wolf-haters’ selective memory and outright misstatements (lies):

    “…in March 2006…a count of 3649 elk.”

    As Marion knows very well, that was not a count…it was a sample. But she uses it to try and claim that there were only 3649 elk in all of the Northern Range.

    “They did not release the number this year.”

    Yes, they did.

    http://www.nps.gov/yell/parknews/nycwwg.htm

    “The Northern Yellowstone Cooperative Wildlife Working Group conducted its annual winter survey of the northern Yellowstone elk population on December 30, 2006. A total of 6,738 elk were counted during good survey conditions.”

  22. Marion, when do you back up these “actual numbers and facts”? Until you provide sources you are just stating your opinion. Also, can you provide me with a documented case of a predator population eating itself into starvation? (I know, the evil enviros only do research that shows wolves are good) Are you aware that without pressure from wolves, elk would not have evolved into the animals that they are today?

    And continually spreading propaganda and insulting the intelligence of the people on this board with your negative unsubstantiated “facts” and refusing to engage in true debate (elkhunter may not share the same viewpoint as me, but he provides some sources to back up his points) is not civil. It is rude and inflammatory.

    By the way, I am still waiting to hear your opinion on wyoming proposing to spend so much to kill wolves when they could spend less and generously compensate ranchers for every wolf kill, confirmed or unconfirmed. You constantly criticize the defenders program as being inadequate. Seems that the state of wyoming, should they actually value their ranchers, could do far better at a cost of a heck of a lot less than 2 million a year. It seems that people like you are out for blood, regardless of the cost.

  23. http://www.greateryellowstonescience.org/topic/elk/elkoverview.html
    here is the 2006 report on the elk in Yellowstone. I don’t think the 2007 is released yet. What is especially informative is the section on the northern herd. Why don’ you ever link anything like this Marion instead of your standard I herd it through the grapevine line.

  24. I realize that I am the one that points out the lack of elk in Yellowstone. No one has yet explained to me how the predators know to cut back on their eating when the prey numbers decline. I have also asked before why does the drought seem to have such an effect on the Yellowstone and Sunlight elk, when other areas of Wyoming have had more severe drought the last few years and our elk herds are flourishing. Look at RMNP, the elk are increasing to the point that they plan to use sharp shooters to thin them, and they too are in a drought situation.
    One could consider how the grizzly problems might be related to a lack of adequate prey and the heavy competition for food. The grizzly that was moved to the research center, and the sow and cub killed after repeated breakins were all skinny and malnourished. There are well over a hundred wolves and several hundred grizzlies, and who knows how many black bears and cougars preying on the same elk. They are eating something.
    The only elk calf count over 20/100 was in March 2006, when 24% calves were counted in a count of 3649 elk. They did not release the number this year. Normal is 40 to 60.
    I know I write things that you prefer not to hear, and I try to keep it civil, but I do try to stick to actual numbers and facts.