Wolverine clearly endangered

I attended the Fish and Wildlife Service’s wolverine listing hearings in Helena.  Opponents, including a number of Montana state legislators as well as MDFWP,  argued that wolverine populations were “stable” or even “increasing” and therefore did not warrant listing under the Endangered Species Act.

While the ill-informed state legislators who testified could be forgiven for not understanding basic biology, MDFWP does not have that excuse. Their opposition to listing of the wolverine and their insistence on continued trapping when the state’s wolverine population is so tiny is both ecologically irresponsible and represents a breach of the public trust to protect Montana’s wildlife heritage.

The most obvious long term threat to wolverine is climate change. That will become a greater threat to wolverine in the future. However, what is ignored by many opponents of listing is that with a population of only 250-300 animals in the entire lower 48 states, and perhaps no more than 175 in Montana, wolverine are already well under what most conservation biologists believe is a minimum number for long term survival.  In other words from a purely biological perspective they are clearly endangered with extinction now, regardless of what happens with global climate change in the future.

Wolverine have one of the lowest reproductive rates of any of Montana’s mammals. Even in the best of circumstances, wolverine can barely balance their population increases against losses. Any increase in mortality, for whatever reason, could cause such a small population to spiral downward to extinction.

In addition, its breeding behavior makes the wolverine more prone to extirpation than other animals. Wolverine males will stake out a territory that over lapses with a number of females. This automatically ensures lower genetic diversity because the one male may breed several females.

With only 250-300 animals, due to this behavioral trait the “effective breeding population” is only 30-40 animals. This tiny reproductive effort almost guarantees a loss in genetic diversity and indeed, recent genetic studies have confirmed that wolverine in the lower 48 states suffer from low genetic diversity compared to wolverine in more robust populations in Canada.

Loss of genetic diversity can lead to all kinds of genetic disorders that can threaten the species survival, and also limits its ability to cope with random stochastic events that individuals with greater genetic diversity might be able to cope with. As a rule of thumb, most geneticists believe that an effective breeding population of at least 500 individuals is needed to ensure the long term survival of carnivore species. With only 35-40 breeding animals in any one year, wolverine are well below this safe threshold.

Worse for the wolverine’s long term survival, the remaining wolverine populations are frequently found in small isolated groups in widely scattered mountain ranges. The survival of the larger population is dependent on the health of these small populations. Trapping or any other increase in mortality could easily wipe out the animals from mountain range to mountain range by removal of just one or two individuals.

As the FWS notes: “Human-caused mortality of wolverines is likely additive to natural mortality due to the low reproductive rate and relatively long life expectancy of wolverines… This means that trapped populations likely live at densities that are lower than carrying capacity, and may need to be reinforced by recruits from untrapped populations to maintain population viability and persistence.”

Even though Montana’s wolverine trapping regulations are conservative, it can still be additive to overall wolverine losses. For instance, the trapping of one male may result in immigration of a new male into the territory. Male wolverine will often attempt to kill the young sired by other males, so it’s entirely possible that the loss of one male to a trapper, may in effect result in the loss of many more wolverine.

Similarly the trapping of a pregnant female or a female with young may result in the starvation of her kits, again creating a loss to the population. If this trapping mortality were to occur in one of the smaller sub populations, it could result in the local extirpation of that population.

As trustees responsible for preserving Montana’s wildlife heritage, MDFWP needs to use biology in formulating policies. And biology clearly warrants endangered listing status under the ESA.




  1. Tom Kuglin Avatar
    Tom Kuglin

    While I appreciate the argument Wuerthner makes, he failed to note that MTFWP made changes to regulations protecting wolverines in small isolated mountain ranges. The former trapping season only took place in core habitat areas where enough habitat exists to sustain populations able to experience harvest.

    If Wuerthner wants to blast MTFWP that’s fine, but he should at least give them credit for what they’ve done to preserve linkage areas and protect the most isolated populations.

  2. Rancher Bob Avatar
    Rancher Bob

    First I believe the wolverine needs some protection, second two things jump out in your article. You said with no more than 175 wolverines in Montana, they are clearly endangered with extinction. Then you went on to say, compared to wolverine in more robust populations in Canada. Is there some blockage of wolverine between Montana’s small population and Canada’s robust population that I don’t know about?

    1. Rancher Bob Avatar
      Rancher Bob

      A third thing jumps out who is MDFWP?
      Unless I miss my guess could Ralph make those D’s into T”s.

    2. Nancy Avatar

      Probably the same kind of “blockage” RB that went on with wolves coming into the state (from Canada) a few decades ago. How many might of been trapped or shot, with little said about it?

      1. Rancher Bob Avatar
        Rancher Bob

        With that comment I take it you have never spent much time in NW Montana, unless you count road trips to Glacier. If you had done some hiking around those parts you would know it’s steep rough ground and has the thickest brush found anywhere in the state IMO. Perfect for all sorts of wildlife not so easy for humans. You would also know animals don’t view habitat in Montana any different than habitat in Canada. I’ve never seen a sign telling animals you are now leaving Canada.
        Crying conspiracy all the time is a bit like crying wolf at some point…

        1. savebears Avatar

          NW Montana is not easy to hunt, it reminds me of when I used to hunt the Oregon cost, so anyone that wanted to get wolves as they are migrating would have to expend way more effort than it is worth. We knew about wolves migrating, saw them every once in a while, but really didn’t pay attention to them. They weren’t causing any problems. It has only come on the radar since the reintroductions occurred.

          We are not really ranch country, not a lot of cows up this way, quite a few horses and a few sheep, but not a big area for livestock predation concerns.

          1. Ida Lupine Avatar
            Ida Lupine

            Sounds beautiful, SB!

        2. Immer Treue Avatar
          Immer Treue

          Rancher Bob,

          Not an argument

          “You would also know animals don’t view habitat in Montana any different than habitat in Canada. I’ve never seen a sign telling animals you are now leaving Canada.”

          But this statement is the same that the “indigenous wolves prior to reintroduction cheerleaders” fail to comprehend/believe.

          How’s your weather today? Gonna be pushing 50 and sunny here. Beautiful with the sun on the snow, but the “mud season” has already begun.

          1. Rancher Bob Avatar
            Rancher Bob

            I was dealing with wolves before reintroduction just nothing that had a den. As Save bears said wolves were crossing the border that’s why NW Montana has so many packs now. Some brave wolf had to be the first, then mark up the country for others to follow.
            Our weather is about the same as yours first bare ground is showing, finally. Not to many days for me since I moved back to Montana I don’t find beautiful. 🙂

            1. Ida Lupine Avatar
              Ida Lupine

              Not to many days for me since I moved back to Montana I don’t find beautiful.

              Lucky! How’s the calving going – it sounded like you’re very busy.

              1. Rancher Bob Avatar
                Rancher Bob

                I do consider my self lucky I spend almost all day everyday outdoors. With all the gloom and doomers telling everyone about no wild spaces or wildlife, well can’t tell that from where I live. Wildlife is what makes life as a rancher great, its what passes those long days in the tractor or out fixing fence. There are so many days that I see some thing happen that most have never seen.
                Calving is going good but with only 2 of us and 24 hours in a day my schedule is set by the cows mostly and I have no control on when one wants to calve.

        3. Nancy Avatar

          “Crying conspiracy all the time is a bit like crying wolf at some point”

          RB, wolves were exterminated by the 30’s and had no protection until the 70’s. For 60 years (20 of them protected years) they never managed to re-populate their old territories until a few were reintroduced in Yellowstone.

          Conspiracy? Or maybe it got a lot harder for the SSS crowd with so much attention being paid to collared packs and individuals.

          Course this has nothing to do with the topic of wolverines being endangered 😉

          “Ranchers also kill wolverines due to the threat they possess towards livestock”


          1. Immer Treue Avatar
            Immer Treue


            “Conspiracy? Or maybe it got a lot harder for the SSS crowd with so much attention being paid to collared packs and individuals.”


            1. Rancher Bob Avatar
              Rancher Bob

              Believe me if there was a real interest in SSS it would be happening. Collars are easy to disable and there are not enough agency people on the ground to stop simple deer poaching if not for the people who spend the most time on the land.
              The old ranchers kill wolverines too, well if you were to ask every rancher in the RMA if they have seen a wolverine you might find 10.

              1. Immer Treue Avatar
                Immer Treue

                Rancher Bob,

                The point I was agreeing with Nancy, that I have also put forth was, prior to introduction there were no wolves in the NRM states save small populations (Nine Mile for one)

                So if no wolves were in the NRM states other than small numbers in Montana, what harm was there in shooting something that wasn’t there: SSS or I thought it was a coyote.

                Not until the reintroductions was there any consequence to shooting a wolf. To switch some names around

                I shot a wolf that wasn’t there
                He wasn’t there again today
                I wish to god he’d go away.

              2. savebears Avatar


                If caught, actually there was penalties to shooting wolves long before the reintroduction, just ask those who paid fines and such when they got caught up here in NW Montana, I know of two guys that paid over $5k each for wolves they shot in the 80’s

              3. Immer Treue Avatar
                Immer Treue


                Not to begin a tit for tat, because I don’t know the circumstances about the two individuals you noted, but there were wolves documented in NW Montana, and the population slowly grew.

                Not so in other areas, as the SSS and I thought it was a coyote crowd probably took care of the wolves that ventured beyond NW Montana, otherwise with the supposed sightings elsewhere, why did wolf numbers not grow prior to introduction?

              4. savebears Avatar


                Reintroduction was like a shot of adrenaline, they were reintroduced into areas that they were not going to have to cross highways, would not be shot for killing livestock and were able to quickly breed with none of the natural situations that happen outside of a protected park setting.

                The population in NW Montana was slowly growing, but still faced all of the challenges of the real world.

                As I said earlier, I strongly disagree with USFWS, on their NW Montana numbers, I live here and saw wolves regularly. As with now, those population estimates were very conservative.

              5. Immer Treue Avatar
                Immer Treue


                “Reintroduction was like a shot of adrenaline, they were reintroduced into areas that they were not going to have to cross highways, would not be shot for killing livestock and were able to quickly breed with none of the natural situations that happen outside of a protected park setting.”

                Agree 100%

                But also there was no guessing game of are wolves present or not. Wolves were present and under the Feds spotlight.
                McCittrick, if memory serves me correct, found out the hard way.

                Prior to this the “indigenous wolves of legend” never had a chance to breed. I know I wasnt there, but if the indigenous (sarcasm intended)/dispersers were present in the past, why did they not breed/increase in numbers the way the reintroduced wolves succeeded.

                I agree with all that you say. All I’m saying, is perhaps outside NW Montana, wolves never had a chance until under the watchful eye of the Feds.

          2. savebears Avatar


            They actually did a pretty good job of inhabiting their old territories up here in NW Montana and it has only been the last few years, we actually many of them collared, but they were and are around, the highest population numbers are up here in my area. And there were no wolves reintroduced in NW Montana, they are all naturally occurring.

            1. Nancy Avatar

              “They actually did a pretty good job of inhabiting their old territories up here in NW Montana”

              Sure about that SB? Their numbers were pretty stagnant in NW Montana til 1990 (Table #4)


              1. savebears Avatar

                Well Nancy,

                Based on my living on ground observations, I happen to disagree with USFWS.

            2. Robert R Avatar
              Robert R

              Savebears don’t let that Based on my living on ground observations get out, JB will persecute you like he tried on me and basically called me a liar.

              1. savebears Avatar

                Robert, not a problem, JB has run me over the coals several times in the last couple of years.

              2. JB Avatar


                Let’s revisit our conversation from the other post:

                JB says:
                March 30, 2013 at 6:43 am


                You said, “that ungulates cannot be hunted without predators being managed.”

                Because of the way you phrased your claim–specifically, your use of the word “cannot”–I do not need a scientific study to falsify it, all I need is a counter example. Perhaps an illustration outside of the politically charged wolf issue is in order? So if you claimed that a human being cannot run a sub-4 minute mile, I don’t need a study to reject this claim, I just need an example that shows the statement is false (it is, though for a long time before it happened, people made this claim).

                Returning to the issue at hand, you made a claim (i.e., ungulates cannot be hunted) premised upon a condition (without management of predators). I have provided three examples to the contrary; that is, three examples of cases where ungulates were hunted alongside protected populations of large carnivores– and I’m quite sure there are many more. These examples disprove your statement. That doesn’t make you a liar (and I never called you one), it just means the statement you made is not correct/factually inaccurate/wrong.”

                I didn’t call you a liar, I pointed out that the claim you made is wrong. A lie would be purposefully making a factually inaccurate claim. I gave you the benefit of the doubt, and assumed you were just unaware of situations that conflict with your assertion.

  3. alf Avatar

    Montana Department of Fish, Wildlife and Parks

    1. Rancher Bob Avatar
      Rancher Bob

      Thanks for the clarity Alf.

  4. timz Avatar

    Are these people so obsessed with killing wildlife for sport they would risk their extinction? Clearly there is something wrong with these people.

    1. Nancy Avatar

      Thinking not so much for sport as for profit, Timz:


  5. Jim Dumas Avatar
    Jim Dumas

    I’ve come to the conclusion that no matter WHAT conditions are for the survival of the wildlife…money talks, and we know what walks. These state legislators aren’t misinformed, IMO, just in somebody’s pocket. It’s a shame that we even have to legislate this, considering what we leave behind will be for our children and grand children. Of course, according to the state and federal government…look them up on the internet.

    1. jon Avatar

      I don’t think these fish and game agencies really care about wildlife like the way a real conservationist does. Fish and game only want these animals out there because they are a “natural resource” that is only there to be “harvested” by trappers and hunters.

  6. Frank Krosnicki Avatar
    Frank Krosnicki

    It appears that greed and a good degree of macho, has ruled and will continue to rule, in sport, and war. It is obvious the Wolverine is going the way of the buffalo and the wolf. Our kids will be able to view them, if at all, in National Parks and Zoos. Worse, the natural balance of nature will be forever altered.

  7. jon Avatar

    Why on earth would anyone want to kill a wolverine in the first place? I hope wolverines are put on the endangered species list. Humans should have absolutely no right to “harvest” wolverines. Montana fish and wild parks has shown itself to be an agency that puts the interests of trappers and hunters over wildlife. There are very few wolverines in Montana and FWP still wants to let trappers kill wolverines.

  8. BryantO Avatar

    The sad truth is,even if it becomes illegal to kill Wolverines,they will still get caught and killed in traps, which are indiscriminate killers of wildlife,protected or not. As scavengers,Wolverines are especially vulnerable to traps,particularly in the dead of winter when there is little else to eat. The number of non-target animals killed in traps is sickening,and any animal killed in a trap dies a horrible miserable death. There is no need to continue this barbaric “sport” for a few hobbiest sociopaths. One thing Wolverines have going for them,is their tendency to disperse long distances,there by mixing up their gene pool and augmenting populations. Apparently they can even cross fairly developed areas,as one looped from the Teton’s to central Colorado,across 2 major interstates.They’ve done better than anyone thought they would.I think their more clever and adaptable than people give them credit, but I do think the few that remain should be protected as much as possible

    1. jon Avatar

      Wolverines and their biggest threat is humans and their traps. The only sure way to protect wolverines from traps is by banning trapping completely in Montana. I don’t see this happening anytime soon, but maybe in the near future. With traps being allowed, you’re going to continue to see many non target animals killed.

  9. Louise Kane Avatar

    I have such difficulty thinking about these individuals that work in a state that could argue against listing the wolverine, insist on trapping and snaring of wolves and other mammals, and generally just disabuse their authority. I wonder if these individuals flunked their biology classes, or do they just drink the kool aid and never have a sane/logical thought again in their heads? I’d think that some must at least gag when drinking that kool aid or try and spit it out. where are the dissenters.

  10. Mtn Mamma Avatar
    Mtn Mamma

    I attended the USFWS Wolverine Public hearing in Denver and commented to support the listing proposal and probable reintroduction of Wolverines to CO. NO legislators spoke. There was one person who “I think” was opposed to the listing but his thoughts and comments were scattered I dont think he knew for sure how he felt, he said something about his friend being killed by a mountain lion.
    The proposed listing come with a big string attached- the wonderful 10J rule. This is supposed to be make the wolverine listing more palatable to those off roaders and ranchers who think they might do their thing above tree-line.

    1. Louise Kane Avatar

      that 10J rule, a farce to placate the usual suspects. I think this provision abrogated the ESA radically from its intent by the American public to protect endangered or threatened species, regardless of economic considerations. Cows, sheep and other livestock will prevail while a species could be extirpated from its range…..bad policy.

      1. savebears Avatar


        At this point in time, it really does not matter what you think of the 10j, it was part of the program, that happened 18 years ago, it can’t be changed, and is no longer in force, get over it and lets move to the future.

        To continue bringing up, is useless, it really has nothing to do with what is going on now!

        1. Elk275 Avatar


          If the 10j was not there or it was recinded, maybe, the ESA just might modified so much that it would no longer be effective. There are powers and forces that could eliminate or change the law.

          1. savebears Avatar

            Without 10J, I believe we would still be in court arguing about reintroduction and there would only be wolves in NW Montana.

        2. SAP Avatar

          Louise is referring to applying 10j to wolverine reintroduction into Colorado, not to the NR wolf reintroduction.

          1. savebears Avatar


            Honestly, I don’t see any reason for 10J in Colorado, concerning the wolverine.

        3. Louise Kane Avatar

          Savebears, we have different philosophies, I don’t think change is ever easy but it is attainable and in the case of most things that need changing,… worthwhile. Wildlife policy and management needs changing. If I don’t like something, I can’t just react by saying things like, “it can’t be changed, and is no longer in force, get over it and lets move to the future” Sorry, its not in my nature.

          1. savebears Avatar

            Where were you when this all started Louise? Why weren’t you fighting back then, like many of us were?

            1. Louise Kane Avatar

              not even worthy of a response SB

              1. savebears Avatar


  11. Lonna O'Leary Avatar
    Lonna O’Leary

    It would seem that wolves aren’t the only victims of MDFW’s stupidity.

  12. Richie G Avatar
    Richie G

    I do not know why we can’t respect each others opinion,the old way of thinking could in some way migrate with new ideas. IMO I do not see why trapping is so important,I guess is some circumstances it is,but it is still cruel,no matter what anybody states. But I side with Louise wildlife should be held in high regard.

  13. savebears Avatar

    “I do not know why we can’t respect each others opinion”

    Richie, this is easy to answer, because most people think their opinion is the right opinion.

    Then you follow it up with this:

    “but it is still cruel,no matter what anybody states”

    See you feel your opinion is the right one, but even though I don’t trap, won’t trap and have never trapped, I know quite a few people, who have opinions that strongly disagrees with yours.

  14. Nancy Avatar

    “I shot a wolf that wasn’t there
    He wasn’t there again today
    I wish to god he’d go away”

    Poignant….. Thanks Immer.

  15. Desertrat Avatar

    There’s a shortage of wolverines in Texas, so I don’t have a dog in this hunt. But from the numbers and from the comments about breeding habits, it seems to me that protection is warranted.

    I’ve been a hunter for about seventy years. Seems to me that unless there is a stable population with some surplus, I can’t hunt.

    It’s only when there is that surplus that I can feed my face or have a furry jacket or coat. Until that condition is obtained, I guess I’m pretty much a protectionist.

    FWIW, I’ve plowed behind a horse (the view never improves) and choused cow-critters out of mesquite thickets. Probably spent more time meddling around in the boonies than a lot of folks have in being upright and breathing.

    Note: It’s more fun to squeak a fox in close and boink him in the nose with my boot toe than to want to shoot the silly little critter. 🙂

  16. Nancy Avatar

    “Note: It’s more fun to squeak a fox in close and boink him in the nose with my boot toe than to want to shoot the silly little critter”

    LOL Desertrat!! Welcome and nice to hear that you’d rather “boink” than kill.

    So guessing your age is somewhere in the 80’s?

  17. Richie G Avatar
    Richie G

    Sb let me be more descriptive, if a person needs to trap because of the elements to cold ,snow I think they have no choice,but that does not take away from the fact it is still cruel on the animal,it leads to much suffering. As for wolves being hunted,I would like a real honest study stating wolves will survive biodiversity. I still do not like the onslaught,I have seen, pictures of a young man with a bow with an arrow trrough the eye of a wolf. I know to yoU that is normal,”I think” not sure what your feelings are,but sb that is cruel,to even a bug,let alone an animal that is a dogs decendent.Look we come from two different environments,I can count the dogs I had in my lifetime, many, over ten. I just rescued a big dog for my one who has no more friends. My love goes very deep for animals,espically dogs and their relatives,not to mention bears.I try to explain this in detail to you before ,because it comes from my heart,you are very analytical that’s your army backround ,again “I think”,BUT WE CAN STILL CONVERSE WITH RESPECT FOR EACH OTHER. Obama has done nothing for wildlife ,and his high speed trains is not truthful either,I really wish Bruce Babbit was back,but this will not happen. The oil now is nonsense,drilling in the artic is bull,Obama has done some common good but not pulled for all of us,he never explains why ,I guess that hurts more.

  18. Snaildarter Avatar

    Sprung traps make a great artifical reef in the bottom of a river

    1. Robert R Avatar
      Robert R

      Snaildarter so you would spring traps?
      Do you know biologist also use leg hold traps to catch wolverines for study. So unless you know 100% that it is a trapper and not a trap used for research don’t be so malicious and destructive.

      1. SAP Avatar

        Robert R – haven’t heard of anyone using leghold traps for research captures of wolverines. See this link – the traps look like little log outhouses.


        Leghold traps are the preferred technique for research captures of wolves, though.

        1. Robert R Avatar
          Robert R

          Sap they also use barrel traps similar to the ones for bears. 4% is low but leg hold traps are used.

George Wuerthner is an ecologist and writer who has published 38 books on various topics related to environmental and natural history. He has visited over 400 designated wilderness areas and over 200 national park units.

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George Wuerthner