Scandlynx, the program that monitors lynx and wolverine in Scandinavia, just issued a report on the status of the Norwegian animals that they tracked over the past year. The report is in Norwegian; readers are welcome to have fun with google translate, which will inform you that in Norway, wolverines are lured into “cubicles” to be fitted with GPS “necklaces” – maybe only the linguistically-obsessed among us find this amusing, however, so I’ll summarize the report here, in English, with a bit of background information. Caveat: I don’t speak Norwegian, and internet translation is always subject to oddities, so don’t hold me to the specifics.
Wolverine and lynx in Norway and Sweden present a unique problem that we fortunately don’t have to deal with here in the US; large herds of domestic reindeer are a major food source for these predators, generating correspondingly high levels of animosity from reindeer herders. Herders receive compensation for losses in both Sweden and Norway, but the compensation takes different forms; in Sweden, herders are paid a flat (and very high, somewhere around $20,000) rate for each successful wolverine den within their herding territory. In Norway, the compensation scheme is similar to our own wolf depredation funds in the western US; herders are given payments per animal on the basis of a confirmed kill. In an argument that precisely parallels arguments from ranchers here in Montana and Wyoming, reindeer herders claim that for each confirmed kill, several others go undetected, and that they are therefore being under-compensated for their losses.
In 2011, the report says, the Norwegian Environment Directorate commissioned a study on the rate of depredation (“murder rate,” according to google, which probably accurately summarizes how the herders feel about it) to try to clarify the actual loss of reindeer to lynx and wolverine. The study covered provinces in central and northern Norway, and will continue for five years. There’s also a component that looks at territoriality of lynx family groups, and a component that tracks collared female lynx and wolverine. The project is tied explicitly to management outcomes, and also considers the effectiveness of current monitoring protocols. The current report is preliminary, not a final report.
Researchers dart animals from helicopters, collar them, and then, with the input of knowledgeable locals, set up a series of stations or traps (the aforementioned “cubicles”) which the animals visit. During the first year of the study, four lynx and 11 wolverine were collared and tracked. The GPS transmitters were set in an intensive mode for a particular period of time, with fixes taken at one hour intervals, in order to determine predation by looking at places where the animals lingered.
The lynx had huge home ranges – 2800 km2 for one of the females, 4200 km2 for one of the males – and seem to be making a living primarily off of roe deer and domestic reindeer, supplemented with the occasional moose calf and some small game (hare, the prey species we most commonly associate with lynx here, comprised only a small part of the diet of these four animals.) The lynx killed six adult and nine calf reindeer, as well as three reindeer classified as “unknown.” These kills occurred throughout the year.
Seven of the 11 wolverine were monitored with the intensive GPS, six wolverine (all male) during the winter, and three (one female, two males) during the summer. The six male wolverine killed between four and six adult reindeer (there seems to be some uncertainty about the status of two of the kills) and three calves during the winter. No depredations were recorded during the summer. Wolverines relied much more heavily on scavenged and previously stored carcasses. The female was recorded killing a roe deer and a bird during the summer, while one of the males added bird and hare to his diet. The researchers specify that they are unsure whether some of the carcasses visited by wolverines in the winter might have been wolverine kills stored away before the study began.
This work is interesting because the researchers are considering some intriguing, landscape-scale systems questions – predator interactions, human landuse, social tolerance, and management and policy issues. It will be interesting to follow the work as it progresses, to see how management and compensation rates change, and to look at how this does or does not increase tolerance for carnivores on the landscape.
If you’re truly obsessed and/or have a lot of time on your hands, you can allegedly track some of the animals in this study here. There is an English version of the page as well. You will have to register, but the process seems to be open to anyone. I still haven’t been able to find the wolverines, however, even after selecting the wolverine project and selecting specific wolverines. So have fun, and if you figure it out, let me know.