Wolverines in the New Year

Just in time for the new year, the January 2012 issue of Smithsonian features a short piece about Keith Aubry’s work in Washington, briefly documenting the adventures of the Cascades’ contingent of wolverines – Xena, Rocky, Chewbacca, Melanie, and Sasha. These wolverines have huge territories, among the largest ever reported for North American wolverines. The article suggests that in two possible mated pairs, the females have larger territories than the males (Xena covers 760 square miles to Chewbacca’s 730, and Melanie defends 560 square miles compared to Rocky’s 440), which seems the inverse of the usual observation that male territories are larger than female territories. The usual ratio is roughly two female territories to every male territory, which means that two (or sometimes more) females share a mate. The researchers haven’t proven that reproduction is occurring in the Cascades, so these animals, even if they overlap with each other, may  be young animals still exploring the world and not yet defending a true territory. Or we may simply not know enough to make any kind of generalization about how female and male wolverines behave when they are in different environments and circumstances.

So what else does the new year hold for wolverines? 2012 will see more wolverine studies in more locations in the US than ever before – long-term monitoring of wolverines in the Greater Yellowstone region continues for the animals originally collared by the Absaroka-Beartooth project, and for the Wildlife Conservation Society’s wolverines. Round River Conservation continues research on the interface between wolverines and winter recreation in Idaho, expanding the study from McCall to Stanley and Fairfield, while further to the north, Idaho Fish and Game, in collaboration with various conservation organizations, launches a second season of camera-trapping for wolverines in the Selkirk, Cabinet, and Purcell ranges. In Oregon, Audrey Magoun and the Oregon Department of Fish and Game are constructing camera trap bait stations across the Wallowa mountains for a second season of work that will hopefully reveal a resident population; the three males photographed this past spring represent the first documentation of wolverines in the range, and if the cameras capture a nursing female this year, it will be the first evidence of a breeding population in the state since the species was declared extirpated in 1936. A camera trap project in Oregon’s Cascades will seek to document wolverines further to the west, while the Cascades Carnivore Project monitors wolverines (among other species) in the Washington Cascades. This means that at least eight projects (there may be more; I’m not sure about the status of the Glacier National Park DNA and camera study) are working on wolverines in the US. Internationally, Canada, Sweden, and Norway continue research on wolverines, and 2012 will see the set-up of camera traps in Mongolia.

2011 was a big year for wolverines. The momentum from the 2010 listing decision and the attention from the PBS wolverine documentary and Doug Chadwick’s book contributed to an increase in public awareness of the species. The discovery of wolverines in the Wallowa mountains in Oregon generated excitement. The launch of three non-invasive, camera and DNA-based studies – one in Oregon, one in Glacier, and one in Idaho – point to the new direction that wolverine research is taking: easier on the animal, and (somewhat) less labor intensive for the people, who have known from the beginning that trying to keep up with this animal is an impossible aspiration.

For me, the year began in Cambodia, contemplating ways to mitigate climate change effects, proceeded to Mongolia for a summer of tracking wolverines through the Altai and Sayan mountains, and wound down in Oregon, where I was privileged to have the opportunity to participate in the Wallowa work. I hope that the coming year holds just as much adventure for everyone, and that 2012 is full of good things for wolverines, wolverine researchers, and wolverine fans everywhere. Thanks to the blog’s readership and to everyone who supports wolverine research and conservation, and Happy New Year!

More Wolverine News

I find myself newly (and happily) initiated into the world of wolverine camera-trapping – more about that later, but in the meantime, check out Yale Environment360‘s recent article on camera-traps as conservation tools. The piece provides an overview of how camera traps are used worldwide to learn about species as diverse as pygmy hippos, African golden cats, and giant muntjacs. Wolverines also get a brief mention.

Equally exciting, a new article in the Journal of Wildlife Management summarizes the findings of the Wildlife Conservation Society’s multi-year Yellowstone Ecosystem wolverine project. I haven’t had a chance to read more than the abstract, but the findings are explored (albeit briefly) in articles in the Bozeman Daily Chronicle and at Mongabay.  I’m looking forward to reading the article itself, especially since it brings some attention to habitat requirements at the southern edge of wolverine range – which has implications for work on the species in Mongolia. I’m also in the middle of reading through a new thesis about wolverine-lynx interactions in Sweden and Norway, which offers another set of insights into gulo requirements in a very different habitat. So it should make for an interesting comparison.

Finally, I try to avoid politics on this blog, but Dan Rather recently stated that, “Newt Gingrich on the move politically is as dangerous as a wounded wolverine.” I have to take issue with this.  Newt doesn’t deserve the compliment, and wolverines don’t deserve the insult. Please, Mr. Rather, let’s start a trend of speaking more respectfully of our wolverine compatriots if we’re going to bring them into politically symbolic public discourse. At the very least, no one should be compared to a wolverine if they don’t look like they could actually climb a mountain.

Brief Updates

I am en route to Oregon to help look into wolverine populations in that state. For the next three weeks I’ll be offline and out of touch – I can’t even express how much I’m looking forward to this.

In the meantime, I thought I’d leave readers with a few brief bits of gulo news:

A wolverine was caught on camera by WWF  in the Russian Altai. These mountains are contiguous with the Mongolian Altai and whatever is going on with the wolverine population in Mongolia is undoubtedly tied to population dynamics in Siberia. So it’s great to have a quick glimpse, even if the bulk of the excitement in this particular article revolves around snow leopards.

A friend of mine pointed me to this Richard Nelson podcast about wolverines. It’s about half an hour long and discusses wolverine biology, and also some interesting Koyukon cultural beliefs about wolverines.

In a recent post about trophic cascades and the wolverine’s role in the ecosystem, I made some statements about wolverine habitat that are not necessarily universally true. Most of my personal experience with wolverines is in mountain ranges at the southern edge of the global range, and so I tend to default to an image of that habitat when I talk about them, and specifically to the Tetons, which is the wolverine-occupied range where I’ve spent the most time. This tendency ignores the bulk of their range in the boreal forests, not to mention variable conditions even between mountain ranges.   So here are a few clarifications:

Wolverines do overlap with wolves and bears in significant portions of their range, and stories abound in Mongolia of wolverines following wolves and feeding on wolf-killed carcasses. In picturing the Tetons, where wolverines are up in the high, rocky peaks and wolf sign is more frequently seen in the valleys, I was picturing a system in which wolverines might, at certain altitudes, be the top predator. But this is unlikely to be consistently true even in the Rockies.

Wolverines are distributed across any landscape in very low densities, and are unlikely to prey on any single species to the extent that they actually have an effect on the population of that species. So saying that wolverines may be a top predator on mountain goats or bighorn sheep in a given area was again a mistranslation between an image in my mind, and science. Depending on what’s going on in a particular wolverine territory, a wolverine might kill a number of animals in a particular herd, but does this affect the overall population of the species? Probably not.

I’m also planning to write a follow-up post about why focusing on trophic cascades is not the only way to think about the value or function of a wolverine. So stay tuned. But in the meantime, I’m off to the mountains to stop speculating and start learning.

 

Trophic Cascades and Some Thoughts on How Wolverines Affect the Ecosystem

Several weeks ago, a ‘trophic cascades’ buzz surged briefly through the media, with a couple of articles – one in Yale Environment360 – talking about the ‘discovery’ that predators are important to ecosystem function, particularly in regulating biodiversity. This is actually not news to the ecology community – studies of trophic cascades from the 1960′s now rank among classic ecological papers – but perhaps it’s taken longer to reach the mainstream than I’d realized.

I’ve been meaning to write about this because people frequently end up on this blog through queries about the wolverine’s role in the ecosystem. This question comes in several forms – “How does the wolverine affect its ecosystem?” “What would happen to the ecosystem if the wolverine went extinct?” “How does the wolverine help the ecosystem?” Unfortunately for the people who are asking these questions, we still have a lot of research to do before we can provide an answer. But looking at the role of predators within ecosystems gives us a place to begin hypothesizing.

What is a trophic cascade anyway? First of all, you need to be familiar with a basic food chain, which is divided into trophic levels – producers (plants), which take energy from the sun; primary consumers, (herbivores), which take energy from (read: eat) the producers; and secondary consumers (carnivores), which take energy from the primary consumers. Sticking to this very simple structure, it’s easy to imagine that those in the top tier of the food chain – the predators – are having an effect on those in the next tier down – the herbivores. To put this into even simpler terms, otters eat sea urchins, therefore otters have an effect on the sea urchin population.

The idea of a trophic cascade takes things beyond the obvious by suggesting that the otters also have an effect on the plants that the sea urchins are eating. This is less intuitive but likewise pretty simple when you think about it: if there are fewer sea urchins, the plants that they eat are likely to experience some benefit. This, in the simplest form possible, is a trophic cascade: a species affecting other species in non-adjacent trophic levels. These effects have been observed most strongly in aquatic ecosystems, where, for example, the extirpation of sea otters led to the elimination of kelp beds as the sea urchin population exploded. In terrestrial systems, trophic cascades occur at both the small (spiders, grasshoppers, and goldenrod) and large (wolves, elk, aspen) scales.

Of course, things aren’t always this straightforward. There’s no such thing as a simple food chain in nature; energy and nutrients cycle through complex networks of production, consumption, and decomposition, and frequently these webs include tertiary consumers (predators that eat other predators) as well as secondary consumers. And conceivably, the same individual could be both a secondary and a tertiary consumer (a heron, for example, might eat an herbivorous rodent or a carnivorous fish.) Direct numerical effects on population aren’t the only consequence of having carnivores around; research on trophic cascades has provided evidence that there is also an ‘ecology of fear,’ whereby the presence of predators changes the behavior of herbivores in ways that can also contribute to trophic cascades.

To complicate things even further, some secondary consumers – generally referred to as ‘apex predators’ – don’t like other secondary consumers – generally referred to as mesocarnivores or mesopredators – and kill them to eliminate competition, which can have an effect on the preferred prey of the mesopredator. (Wolves don’t like coyotes, and kill them when they can; coyotes prey extensively on pronghorn fawns. Since the wolf reintroduction to Yellowstone, coyote numbers have dropped and pronghorn fawn survival rates have risen. A number of other examples of this phenomenon in reverse – eg, removing apex predators from ecosystems, which is sometimes referred to as ‘mesocarnivore release’ -  can be found here.) If this doesn’t give you enough to mull over in contemplating the complicated relationships among species, consider that there’s also evidence that wolves in Yellowstone, by reducing elk numbers and thereby encouraging the growth of willows and aspens, have allowed the return of certain rare songbirds by providing nesting habitat. As to the effects that those songbirds are undoubtedly having on their food networks, well….you can imagine that the repercussions go on and on.

For a long time, ecologists thought that ecosystem structure was regulated from the bottom up, by resource availability. Only with the advent of work on trophic cascades did people begin to appreciate that top-down regulation and structuring were also occurring. The realization was significant for conservation advocates because it gave a much more quantifiable value to predators, which were traditionally reviled for depleting supplies of game. Traditional Western wildlife management, from its inception, revolved around the removal of predators to ‘benefit’ the ecosystem as a whole. Evidence of top-down ecosystem regulation finally provided some rationale for keeping predators on the landscape (aside from “These animals are cool and inspiring,” which, unfortunately but understandably, has never been enough for some people.)

How does this relate to wolverines? Wolverines straddle the line between being a top predator and being a mesocarnivore; they hunt, they scavenge, they can scare grizzlies or wolves off a kill, but they are also killed by larger predators. Among the high peaks of the Lower 48, where there isn’t much apparent overlap with bears and wolves, they are likely the top predator on bighorn sheep and mountain goats, although they also apparently rely on sheep and goats that fall off cliffs. They consume a wide array of small mammals and may be consuming some plants (chemical compounds derived from vegetation are found in wolverine musk) although obviously not enough to have a major effect on plant communities. The point is, they interact with a number of different species because they are, within their habitat, generalists. One could speculate that a female wolverine denning in an area near pika colonies might have an effect on those pika colonies, which in turn could effect the plants on which the pikas graze. It could also regulate disease transmission among pika colonies by thinning out the population and reducing the density of vectors; conversely, it might have a negative effect on dispersal and the founding of new pika colonies. We could also hypothesize that wolverines might preferentially prey on lambs or kids (the goat variety, not the human….), and that this in turn would restructure the plant communities and maybe the distribution of goat or sheep herds in their high-altitude pastures. Finally – a question that the scientists who work on trophic cascades haven’t, as far as I know, asked – we could begin to test some hypotheses about whether mid-level carnivores or scavengers can affect ecosystems as a whole – for example, if wolverines are preferentially hunting mountain goat kids, do they reduce the mountain goat population enough to exclude some other predator? Do wolverines compete with raptors (by burying carrion, for example) in such a way that the raptors and/or the raptors’ preferred prey is affected? At the northern extent of their range, is wolverine predation on caribou calves high enough to have an impact on the caribou and if so, how does that affect the plants on which caribou graze? Are wolverines on the landscape playing any role in rates of wolf predation by pushing wolves off kills and forcing a pack to hunt more frequently as a result? Honestly, it seems fairly ridiculous to imagine that this might be true – but who knows?

Everything that I’ve written in the paragraph above is entirely speculative, and the alpine tundra ecosystems in which the wolverine lives at the southern edge of its range aren’t necessarily well understood as systems. The point is that we don’t know exactly how wolverines affect ecosystems in either the northern or the southern parts of their range, but it’s likely that they do in some way, and there are a million possibilities to explore. For people who are looking for an answer to how wolverines affect the ecosystem, hopefully the idea of trophic cascades gives you a place to start thinking about the many connections that exist among species and the many possibilities for asking targeted questions on the topic.

Potential Change to Polar Bear ESA Rule

When the polar bear was listed as threatened under the Endangered Species Act in 2008, the Bush Administration issued a rule stating that the ESA couldn’t be used to regulate greenhouse gas emissions even if a listing was due to climate change. This rule represented a blow to conservationists, rendering the ESA incapable of being invoked to address threats to climate sensitive wildlife. The polar bear case was complicated by a number of other factors including the threats posed by energy development in the Arctic, the politics of hunting and indigenous rights in Canada, and the clear reluctance of Bush Administration officials to list any species without the threat of legal action, and even then to do so minimally and grudgingly. But reduced to essentials, the decision meant that the polar bear and its fellow climate sensitive species – notably, the wolverine, the pika, and the walrus, all of which have been considered for listing between 2008 and the present – would be excluded from the protections that the ESA offers to species threatened by in-habitat issues like point source pollution, destruction of habitat, and over-harvesting.

Last week, in response to a lawsuit by four environmental organizations, a district judge handed down a ruling that the government’s failure to conduct an environmental review before issuing the rule constituted an error, and sent the decision back to the government to obtain a review. This decision (summarized by NPR, detailed in an article in the LA Times, and commented upon by the environmental groups involved) opens a tiny window through which environmental groups might maneuver to obtain stronger protections for climate sensitive wildlife.

Unfortunately, though, the details of the decision suggest that this won’t happen. The judge ruled that the lack of an environmental review was a serious problem, but affirmed that the government has the right to decide what types of harm are allowable to species listed as ‘threatened’ rather than ‘endangered.’ The polar bear population, classified at this lower level of risk, is deemed robust enough to withstand further losses, and therefore a population reduction due to climate change is – officially, anyway – not a cause for concern. (The environmental groups sued to upgrade the polar bear’s status to endangered earlier this year, but lost.) The Obama administration has until November 17th to submit a timeline for writing the review.

What does this mean for wolverines? I’ve devoted previous posts to the paradox of the push to list the species, and although I believe that the scientific evidence states that the wolverine should be on the list, I’m torn at the thought of spending huge amounts of money on a species when only the proximate causes of the threat are being addressed; if that money could go to actually saving a species facing in situ threats, maybe it would be better to put the money towards that species. But if the polar bear rule is struck down and the ESA is enabled as a tool for regulating ex situ threats like greenhouse gas emissions, I can stop coping with this split-personality problem and cheer for listing without any reservation. (Or, of course, if we actually adequately fund the USFWS, we could work on saving all the species, thus likewise eliminating conflict over the issue….)

Gulos are currently candidate species for listing, with a final decision due by 2013. For so many reasons, I wish the decision on the polar bear rule had come down earlier, not in the run-up to an election year; the timing means that the decision will be more subject than usual to the pull of politics. Regardless, though, it at least represents an acknowledgement that the rule was made too hastily and warrants review. Hopefully by 2013, if the wolverine is listed, the listing will actually offer protection.

On the subject of climate change, a very short interview with climate scientist Synte Peacock highlights her interest in wolverines and her work modeling snowpack conditions in the wolverine’s North American habitat. In the ongoing process of building a chain of evidence that wolverines are threatened by climate change effects in the US, her work shows that snowpack conditions at the core of wolverine range are likely to decline over the next century. The study isn’t cheerful, but it does at least offer multiple scenarios (depending on how we act – or don’t – on the threats) and some are better than others. So that’s a (very) small bright side.

 

Upcoming Gulo Events

Gianna Savoie will be speaking about her film Wolverine: Chasing the Phantom at REI in Bozeman on October 19th. The talk runs from 6:30 to 8:00pm. The event is free, but limited to 30 participants. You can sign up, and find details about the location, here; there are 16 spots left, so register now if you want to reserve a seat.

Further out on the calendar, on November 9th wolverine biologist Audrey Magoun will give a talk on the discovery of wolverines in the Wallowa Mountains of Oregon. Audrey pioneered wolverine research in Alaska and developed a unique system to identify wolverines via camera-trap; it was the deployment of these camera stations last winter that provided the first evidence of wolverines in eastern Oregon since 1936.  The talk will be held in Portland, at the Billy Frank Jr. Conference Center of the Ecotrust Building, 721 NW Ninth Ave. An overview of the event can be found here. This lecture is also free, but requires registration. (Are wolverines so popular that we now have to impose limits on attendance? A good sign of a growing constituency, I hope….)

Dr. Healy Hamilton on Temperature and Precipitation Changes in the GYE

This talk is going to be harder to summarize without the visuals used during the presentation. I’m googling to see if I can find an online copy of some of the graphs and maps that Dr. Hamilton used to illustrate her work – it looks like they are not immediately available. But in summary, GYC and Dr. Hamilton have partnered to look in detail at the GYE to try to develop some idea of what is actually going on with climate, based on weather station data from the past century. Using USDA information on temperature and precipitation, they’ve constructed a historical timeline of average temperature and precipitation from 1900-1970, and then looked at places where, over the past thirty years, temperature or precipitation have varied by more than two standard deviations from the 1900-1970 averages. For people without a background in statistics, two standard deviations from average is significant because about 98% of variation in any situation should fall within the boundaries of two standard deviations from whatever the average of the data is. So if you see something that is more than two standard deviations from the average, you can be pretty sure that something out of the ordinary is occurring.

The standard narrative of climate change around the world is that temperature is rising, which is true, but how this plays out a local scale can be extremely varied. This is why there’s still so much room to sow doubt and confusion over the climate science.

Dr. Hamilton’s data suggest that average minimum temperatures are increasing, particularly in late winter and early spring, but that average maximum temperatures are not increasing. This means that, as Dr. Hamilton puts it, “we are losing climate space” on the colder end of the spectrum, but not necessarily gaining it on the warmer end. Precipitation seems to be decreasing in July, but by October it’s increasing; by December, it’s leveled out and remains approximately the same as it has been since 1900. A few places seemed resistant to the general loss of minimum temperatures, among them the northwestern edge of the Wind River Range.

So what does all of this mean for the future of the ecosystem? Difficult to say for sure, but this is certainly the next step in the climate change narrative – boring down into local trends and trying to create scenarios that will allow planning for adaptation.

Three things in the presentation were particularly striking. The first was Dr. Hamilton’s opening statement, in which she briefly addressed the politics of climate change and then said she didn’t want to talk about it.  Who does? I sympathize with her. But whether we want to talk about it or not, the gridlock over climate change policy is the problem with which we really need to be wrestling. Falling back on science and scientific management, generating more data and more maps, isn’t going to convince people who already believe that researchers like Dr. Hamilton are being paid off to do the work they do. (They aren’t. Just because the right wing pays its ‘scientists’ to generate data doesn’t mean that real researchers lack integrity.)

The second was the predominance of maps in the presentation. Some colleagues of mine have an old joke that asserts that when environmentalists are in doubt about what to do, they fall back on producing maps. Sure enough, in the face of climate change policy gridlock, we are indeed producing more maps. The maps are beautiful, fascinating, informative, and represent great research. Hopefully they will make an important contribution to conservation planning in the GYE. But maps aren’t solutions, and to put these maps to good use, we need something more.

The third thing, which I found hopeful and which partially addresses the concern above, was the suggestion that the GYE would be the test case for how to use tools like these maps, because the region  has such a broad conservation constituency. Let’s hope that the support for conservation values does translate to some form of planning for ecosystem resilience at a broad scale. But the challenges are still manifold, and those problems aren’t scientific problems – they’re people problems, and they’re governance problems.

 

Blogging Live from the GYC Meeting!

I’ve always wished – a dorky wish, to be sure – that things like really cool wildlife could garner as much attention as dippy pop stars and/or demented political candidates making asinine statements. Sadly, it seems that Sarah Palin’s enduring ability to behave stupidly, for example, or Hollywood’s most recent fashion choices at various awards ceremonies, always garner more tweets and live blogging activity than, say, the annual meeting of the Society for Conservation Biology. Why is this? Surely it’s a sign of a society with its priorities in the wrong place….

In an attempt to set American culture back on the right track, I am going to blog live from the Greater Yellowstone Coalition meeting here in Jackson Hole today. This year’s meeting focuses on climate sensitive wildlife, and Doug Chadwick, long-term volunteer with the Glacier National Park wolverine project and author of The Wolverine Way, will be the keynote speaker. He has recently spent time in the Gobi working with the mazaalai, the Gobi bear, another species under intense threat due to climate shifts, so I anticipate a great speech. In addition, we will also be hearing from Dr. Charlie Love on glaciers in the Rockies, Dr. Bob Greswell on the effects of climate change on cutthroat trout, Dr. Healy Hamilton on using biodiversity informatics for conservation, and author Gretel Ehrlich on how you sum all of these issues up in a compelling piece of literature that will move people to love and care for the places that they live. The who’s-who of the Yellowstone conservation world will certainly be here as well, so it promises to be a thrilling day.

By the way, I don’t think I’ve actually ever followed a live blog before, so I’m not sure I’ll be able to spoof appropriately. But I will be sure to let you all know what everyone is wearing. (Yvon Chouinard and his team are, rumor has it, the designers of choice for this event.) Blogging activity will be interrupted mid-day during a fire ecology field trip (I do not have a smart phone, and carrying my computer into a burn is probably unwise) but will resume in the evening.

Okay. So where do I start?

“Sunrise over pristine and gorgeous mountains emphasizing need to conserve inspiring natural places. About to head down to breakfast to get some coffee so that blog posts become more coherent.”

Stay tuned.

 

Where Wolverines Are Born

When I set out last week with the coordinates for F3′s den programmed into my GPS and the site marked on a series of paper maps, I couldn’t shake a feeling that approached sheer giddiness. The opportunity to examine a wolverine den site is akin to winning some kind of wildlife biology lottery; the dens are as inherently rare as the species, and the dens that are known to science are even fewer. Only around 15 have been documented in the Lower 48, leaving a huge gap in our knowledge of reproductive dynamics. For years, F3 had failed to den, and the instruments on our other female, F133, had died, so we had no way of knowing whether she had had kits. When F3 evidently did den this year, I was ecstatic, but I was also in Cambodia. I was starting to think that I would never have a chance to investigate a den site. When I made it back to the Rockies earlier than expected, in August, getting to F3′s den site was one of my priorities.

A crew visited the den in May, when the snow was still on the ground, and some of the same crew members had gone back once the snow melted, in July, to investigate the site and to see if they could find scat samples. The spring crew hadn’t seen the kits or verified their existence, so however strong the circumstantial evidence, we couldn’t be certain that the site was a den instead of a food cache, and we couldn’t say with confidence that F3 and M57 had reproduced. The July crew had looked for latrine sites, which are proof that a site was used as a den. And the crew found them in abundance, pulling out a number of scat samples for analysis. They hadn’t gone digging for the kits or attempted to instrument the babies in May because of funding constraints, so the scat samples, in addition to confirming that this was a den site, also offered a chance to identify new individuals and perhaps determine their sex.

The important work had already been done, and my own trip was half fun and half pilgrimage. I wanted to visit the place where F3 had – presumably – brought her first kits into the world, and I wanted, after nearly a year away, to be back in mountains that form some part of the mental and emotional landscape of home.

The route into that landscape followed a trail for a while, and then cut away from the trail and up gentle south facing slopes, warm with late summer sun and the scent of dust and pine. At the crest of a pass, the world dropped away, the slope plunging steep and precarious into a narrow pine-cloaked valley that swept back to intersect with the endless marching peaks of the high Absarokas. These north-facing slopes were utterly different from the warm hills I’d just left; I had to edge my way down, dancing between tree trunks for support, the force of gravity and the angle of the pitch propelling me towards freefall. The trees were thick, the shade dense, the temperature so much cooler that I paused to put on my jacket and hat.

Possible wolverine scat under a log, about 0.4 miles from the den site.

As I crouched to pull out my hat, I noticed a huge pile of scat under a log near my feet. I was still a half mile from the den site, but the scat was definitely carnivore and seemed mustelid. It was a bit small, but they were kits, after all. I hadn’t been expecting to collect samples but I did have two ziploc bags on hand, so I shoveled the scat and a large chunk of fur into the bags, GPSed the location, and continued to slide downhill through the dense, cold forest and small open meadows. These meadows were saturated – with streams, with flowers, with warmer patches of sunlight, and with the same breathless silence that hung over the trees. The quiet was ancient and deep and almost tangible, so that I felt like I was diving down and further down through a substance like water, into some other world.

Among all the trees, I wasn’t sure how I would ever find the actual den site, but as I crossed another meadow and stopped to look across the stream that drained it, a patch of pink fluttered from over the water. In May, the crew had tied flagging tape to the tree branches directly above the six entrances to the den. Now, in August, with the snow melted, the tape hung fifteen feet overhead. Beneath the tape, F3′s excavated snow tunnels had led down to cavities sheltered by fallen trees. I’d found the tape, and I’d found the den.

A wolverine's-eye view of part of the den site. The chambers were beneath the downed trees. Note human for scale, and pink tape in tree overhead. This marks the approximate depth of the snow in May.

The crew had already collected all the samples, and I spent a long time simply exploring the area and then sitting and basking in the vast silence. The multiple den entrances had sprawled across an area of approximately 120 m²; the tunnels were probably connected beneath the surface. Beneath the largest of the downed trees on the ground, a hollow against the root ball seemed to have served as one chamber, with two others located among the branches further up the trunk. Against another downed tree, another flattened area between branches suggested a chamber as well.

One of the hollows that was part of F3's den site.

I tried to imagine the family down under the snow in a world of compressed ice, first as newborns and later as more active babies. Did F3 dig new tunnels as the kits grew, or had she constructed the whole network at once? Did she move them from place to place as waste accumulated? At what point did the babies begin to move around through the tunnels on their own? Or did they simply wait, curled up around each other for warmth, where F3 left them when she went out to forage? Had M57 come down here as well? The crew in May had heard his signal and found his tracks crossing their own ski trail; he had traveled directly to the den from the distant location where the crew had heard his signal earlier in the day. If he had gone into the den, what did he do while he was down there? Did he bring them food? Keep an eye on things while F3 was out? (She hadn’t been in the den the day the crew visited.) Play with the kits, add his warmth to theirs, wrestle with them to toughen them up for the outside world? When had they left this place, and did they ever return?

I looked up from the logs, scanned the trees, but everything remained still – no sign of wolverines, or of anything else. The most important ecological question – why here? – remained unanswered, but my personal reasons for being there had been more than fulfilled. I was overwhelmed again by the extraordinary stillness of the place. Later, it came to me that the meadow was suffused with a sense of peace that goes far beyond our normal conceptions of that word – the peace of the Wild, a peace that is so powerful because of its utter indifference to human concerns or moral order, a peace that is edged with on-going loss and ferocity and struggle that are, nevertheless, somehow more acceptable and less alien in places like this. It was, I hoped, a good place to be born a wolverine, and I was profoundly grateful to have seen it.

Idaho Snowmobile Study

A quick note from Ulaanbaatar, before I head back into the field: An article about the snowmobile study in the Payette National Forest in Idaho gives an overview of the study and a glimpse of some of the potential outcomes. All of the participants in the study – from the wildlife biologists to the snowmobile association representatives – come across as committed to good science, which is great news for wolverines (and for people who might otherwise be caught in an endless cycle of anecdotes and arguments about what’s really going on.)

The article concludes that since wolverines are currently inhabiting areas with winter recreation, wolverines may not be disturbed at all by snowmobiles and skiers, but this is probably a premature assessment. We can certainly hope that winter recreation won’t be a problem for wolverines, but we need to wait to see what the study says about the most critically important segment of the population, reproductive females, before we conclude that everything is fine.