Sweden Incidents in Wolverine Research

I’m the first to admit that I give Scandinavian wolverine research less attention than it deserves. I’ve never been there, I don’t know the researchers or the research or the policy situation as well as I know the North American and Mongolian situations, and it’s easy to put aside detailed write-ups when I can’t draw on background expertise to pull together a quick post. Things that take more background work on my part tend to get written about less, because writing this blog is uncompensated intellectual labor (or escapist fun; it varies by the day) and the greater the investment, the less likely something is to get written.

Something apparently happened recently in Sweden, however, and no one can figure out quite what the so-called “Sweden Incident” entailed. Since the question remains open, the Sweden Incident may or may not involve wolverines. So I thought this would be a good chance to run down a few of the Swedish wolverine resources, to remind all you wolverine-interested people that there is, in fact, some pretty cool stuff happening in Sweden. And this stuff is verifiably and objectively true. So enjoy.

Scandlynx is a joint project with participation by both Sweden and Norway. They monitor lynx and wolverine and put out some interesting research. The website is available in Swedish, Norwegian, and English.

The Swedish Wolverine Project has its own page, where you can learn more about the specifics of wolverine research, check out a good bibliography with links to research publications, and enjoy a brief synopses of wolverine ecology and life history.

In less savory news, Swedish wolverines regularly depredate on domestic reindeer. This creates a lot of conflict with the reindeer herders, but has resulted in some innovative experimental compensation schemes. Here in the US, of course, our biggest conflict is between livestock producers and wolves, and we tend to compensate after a wolf pack depredates. Ranchers aren’t keen on this way of doing things, because they have to prove that the depredation happened, and they claim that far more animals are killed by wolves than those that they can find and verify. Consequently, they claim, the rate of compensation is far too low to actually pay for their losses.

Sweden solved this problem by instituting a preemptive payment scheme for wolverine dens on Sami herder territories. Rather than compensating after a depredation happens, the Swedish government pays for “conservation performance” when a den is successful. While this compensation scheme seems to be better at addressing herder concerns, poaching remains a problem; as of 2009, at least, up to 60% of wolverine mortalities in Scandinavia were due to poaching. And there’s also evidence that national parks in northern Sweden, rather than serving as places of protection for wildlife, are actually the loci of greater illegal hunting. This may be due to the fact that these parks are large and remote, and therefore difficult to patrol.

The intensive monitoring program in Sweden allows researchers there to look at predator interactions in a way that is difficult elsewhere. Ecology as a field has spent a lot of time studying predator-prey dynamics, but less time understanding how suites of carnivores interact with each other. The Swedish wolverine project is able to monitor both lynx and wolverines on reindeer herding territories, and has produced some interesting work on how these two species share resources. It appears that the resource-sharing strategy in Sweden primarily involves avoidance; although wolverines scavenge off lynx kills, the two species don’t interact that often. The most detailed work on this topic is Jenny Mattisson’s 2011 dissertation. Follow-up work on wolverine-lynx interactions is also available.

Perhaps the most intriguing Sweden Incident in the wolverine world, however, is the recent establishment of a population in a previously uninhabited boreal forest region of southern Sweden. In a paper published last year, the authors contend that Sweden’s monitoring and management programs need to adapt to account for this new population, since most monitoring protocols and management objectives are related to populations in northern alpine herding regions. They also mention that the presence of this wolverine population in an area where the snow melts earlier in the spring is evidence that wolverines may not be as dependent on late spring snow as the Copeland et al 2010 snow model paper suggests. I have a lot of thoughts on that topic, but for now I’ll just confine myself to two points. First, the original snow model paper pointed out that north of 54 latitude, the relationship between spring snow and wolverine presence breaks down, and this site is substantially farther to the north, somewhere around 60 latitude. So in fact, the original snow model paper accurately predicted this exact situation. Second, the framing of questions about wolverine snow-dependency has becoming depressingly binary, because of the management implications for listing in the US, with a tendency towards papers that highlight apparent exceptions to very specific features of the model to make claims that apply to the particular US policy questions, without taking the larger picture into account. This population in southern Sweden, similar to populations north of 54 latitude in Canada, offers us a chance to ask a much bigger set of questions about wolverine habitat requirements and the relationship between cold climates and wolverine persistence. I’m looking forward to learning more about this.

Finally, though, if certain individuals are implying that there is a Swedish Incident or Incidents involving terrorizing of the good and upstanding people of Sweden, our best avenue of analysis would probably focus on moose. As documented here, rowdy drunken moose are apparently a perennial issue in Sweden, destroying property, breaking into stores, holding public orgies, and even occasionally killing people. The establishment of that southern wolverine population followed the implementation of a moose hunting season in the region where the wolverines have taken up residence – perhaps that season was instituted in response to aggressive moose issues? In any case, there’s a theory that gut piles left by moose hunters might actually be responsible for supplementing wolverines in that region and giving them a foothold in a place where they wouldn’t otherwise be able to persist, proving once again that ecosystems are complex, that humans are embedded within them, and that thinking about complexity, in complex and nuanced ways, is necessary to understanding the world we live in.

Here’s hoping that whatever the Sweden Incident actually was, it doesn’t impede the ability of Swedish wolverine researchers to keep up their good and interesting work on the species.








Updates, Uncertainty, a Couple of Bears, and a Moose

Once in a while, the whole world implodes.

About three months ago, I started the process required to get a study visa in order to return to Mongolia. I am at the point where I have to do this, for various complicated bureaucratic reasons, the details of which I will spare my readers. When I left Mongolia in June, I anticipated a nice month in the States catching up with family and friends, picking up cameras and supplies for the wolverine/snow leopard project in the Darhad, and heading back to get the project started. Through a series of circumstances, however, the visa application – a single step from completion – fell through, and I found myself stuck in Bozeman, Montana, while I tried to figure out if I could return to the country this year. As places to be stuck go, Bozeman is lovely, but the state of mind generated by the total uncertainty about what you will be doing a month in the future is not. If there’s a kryptonite to the sort of personality that enjoys running around in the mountains chasing wildlife and writing about it, it’s bureaucracy. The past few weeks have passed in a haze of paralysis over how to sort all of this out, what to do with regards to the camera project (I had planned on being in the Darhad working with the protected areas’ rangers as of last week, and time is getting short), and so on. I don’t need to bore anyone with the details, but it’s also not a very good mental place from which to spin engaging narratives about one’s pursuits in the world of wildlife research. So the blog has been hibernating. I’m close to resolution, though, so hopefully (although this is still an optimistic interpretation) I will soon be reporting on my pursuit of wolverines and snow leopards from Mongolia.

In the meantime, though, I’ve been hiking up into the Bridgers to retrieve camera traps that I set up there this past winter and spring, in affiliation with the Forest Service, and with the WCS wolverine project, whose director Bob Inman was good enough to loan me some of the parts to make the stations. I haven’t written much about this endeavor here on the blog, but I wanted to test my cameras before taking them to Mongolia, and the wolverine status of the scattered, so-called island ranges of Montana remains relatively uncertain. The Crazies, to the east of the Bridgers, would have been my preferred range to test, but lacking a four wheel drive vehicle (yes, I’m still driving a car better suited to the streets of Boston than the back roads of Montana….) I had to settle for a more accessible site. The Bridger range is very small, tiny in wolverine terms, and could probably hold one, or at most two, reproductive females. I doubted that we would find any wolverines, but I was curious to see what might turn up (and exactly how much effort it takes for a single individual to run a wolverine camera trapping endeavor across even a small swath of the landscape.) In February, I set up five cameras, two on the east side of the range and two on the west side, all just below the ridge. I set up a fifth camera in the Bangtails, the rolling, low range just to the east of the Bridgers, where a woman had taken a photo of a wolverine while mountain biking last year. I took down two of the cameras in mid-March, shortly before I departed for Mongolia, but the other three remained in place until early July.

As expected, I did not detect any wolverines – this doesn’t mean that they aren’t there, though, because there were a number of things about the study that were not optimal for wolverine detection. In a more focused update, I’m going to write more about what I learned about wolverine camera trapping from this project, but in the meantime, here are some images that did turn up, and that I particularly enjoyed as they popped up when I was sorting through thousands and thousands of photos of carnivorous squirrels.


Ghost bear in the Bridgers. I was taken aback by this photo when I first saw it, but the camera exposure can substantially invert or alter tone, so despite early hopes that I’d discovered a rogue polar bear population in Montana, this is a black bear. (The trees on which I set up these cameras were too close together, one of those lessons that I’ll discuss soon, but ideally you should be able to see the run pole and the ground beneath it, to record visits of animals that don’t climb the run pole.)


This may be the same bear, several days later, paying a visit with her cub.


This critter contemplated the bones for several frames, displaying only its ears, and I was worried that it would never give me a portrait so that I could tell whether it was an elk or a moose.


Luckily it did eventually reveal its identity – and took advantage of the wolverine apparatus to scratch its nose.