By SEAN PATRICK FARRELL
nytimes.com
I write about a new group called Adventurers and Scientists for Conservation that is working to link outdoors types with researchers who can benefit from their back-country skills and data-gathering. I reported from western Montana, where Gregg Treinish, the group’s founder, was jointly leading a weekend expedition of a dozen volunteers tracking the wolverine.
Their data would go to Steve Gehman, a biologist who has spent 15 years studying the animal through his nonprofit research group, Wild Things Unlimited. I asked Mr. Gehman to explain what it is about the wolverine that keeps him returning to study the animal year after year, why he prefers to track and observe rather than rely on technology like radio collars, and the value of volunteer science in general. Here are some excerpts from our conversation, edited for brevity and clarity:
Q.When we were in Montana, I asked you about public knowledge of wolverines. You noted that sometimes people ask if a wolverine is a female wolf, or immediately want to talk about Hugh Jackman’s character in the “X-Men” movie franchise. In other words, they’re not exactly familiar animals. Still, they’re fascinating: they live on tough terrain, can be ferocious defenders of their food, and, as I realized when we were tracking them, can travel a good distance in a day. But why have you devoted so much of your career to them?
A.Animals like the wolverine and grizzly bear resonate with me because they rely on wilderness for survival — they spend most of their lives in wild places. This also means that they are difficult to study; I suppose that the physical and logistical challenges of this type of research are appealing to me (although less appealing as I get older)!
Q.Tromping after the wolverine is tough work. It almost seems tailor-made for the rugged outdoors types (we had ice climbers, long distance backpackers and back-country skiers along with us) that Gregg Treinish has been recruiting. How much of a difference does it make to have more bodies in the woods with you?
A.Trained, competent volunteers can make a huge difference for us. If we can break into multiple teams and follow different wolverine or lynx trail segments, it really increases our ability to document the animals’ travel patterns and activities and raises the probability of finding scat and hair samples that might provide the DNA for identifying individual wolverines or lynxes. The more miles of animal trail we follow, the more useful our research results will be.
Q.You take a fairly low-tech approach to tracking; you don’t use radio collars or trap animals. Why is that? The kind of tracking you and Gregg were teaching the volunteers can be done by anyone with a G.P.S., a camera and a few plastic bags.
A.Our choice of methods is based on philosophy and practicality. I have been associated with numerous studies that trapped and radio-collared animals, and I know firsthand that some animals suffer and some animals die as a result of trapping, drugging and handling. I believe that these activities probably also have more subtle and undocumented impacts that adversely affect the lives of the study animals. While I realize that radio-telemetry has the power to provide large volumes of locational data, I believe that it is overused in the wildlife field. It should only be used when the results have the potential to play a vital role in the conservation of the study species or population.
So much for my philosophy – with regard to practicality, radio-telemetry studies are very expensive (traps and trapping crews, collars, veterinary services, airplane flights, satellite information, et cetera). It’s hard enough for large organizations to maintain the funding for such studies, and we are a very small organization with a limited budget. So we use a more low-tech approach (although we do use G.P.S., G.I.S. and DNA sampling, which are pretty high-tech tools) and try to maintain a sustainable budget that allows to be effective over the long term. (This is Wild Things Unlimited’s15th winter of conducting snow-tracking surveys and studying rare carnivores in the northern Rocky Mountains.)
Q.You are starting to use some sophisticated camera traps that record wolverine and lynx images — what do you learn from those? And can you tell me more about the DNA analysis
A.If we get good enough images from the cameras, we are able to identify individual wolverines from markings on their heads, necks, chests and feet. That helps us to count the number of wolverines in a particular area. Because cameras work round the clock regardless of weather conditions, they can also provide information related to when wolverines are in certain places and what times of day they are active. This helps to supplement our tracking data.
If hair and scat samples contain high-quality DNA, they can also reveal the identity of individual wolverines or lynxes and thereby help us to count animals and to learn the sex ratio in a sub-population. Through repeated sampling and by associating the DNA samples with the trails that we follow, we can begin to learn how different individuals use the landscape, and we can track the activities of individuals over multiple years.
Q.We were in a part of Montana that wasn’t thought to be wolverine habitat until fairly recently. Your work there has shown that they’re using lower-elevation forests. What else don’t we know about wolverines that might help us understand how best to protect them and their habitat?
A.We don’t know enough about wolverines’ tolerance for, and adaptability to, human activity. How do different winter activities like back-country skiing, snowmobiling, ice-climbing and snow-shoeing and winter camping affect wolverines’ selection of habitat and overall survival? Are there certain amounts or frequencies of human activity that are acceptable to wolverines? Are wolverines capable of adapting to some activities, or some levels of human activity? These are just a few of the many questions regarding the potential impacts of humans on wolverines and wolverine habitat.
Q.So the wolverine, once driven from Montana by heavy trapping and poisoning, has returned, traveling from the Canadian Rockies, and has even been seen in other places like Michigan and California. Still, their numbers in the lower 48 states are still quite low — fewer than 500 — and among that number, only a few dozen are capable of mating. Do we have any idea what a healthy population would look like?
A.I’m not a population biologist, so I will not venture too far into this. However, there is a general rule of thumb called the 50-500 rule that says there should be at least 50 breeding animals for any population’s short-term viability and at least 500 breeding individuals for long-term viability. For wide-ranging and sparsely distributed animals, connectivity of habitat is also required to maintain a healthy population.
Q.Are wolverines really that rare, or is it that they just avoid humans? I got quite a thrill seeing those perfect prints in the snow — we could count each toe and sometimes see where their claws had dragged. Do you still get excited when you’re on the trail of a wolverine?
A.I have seen wolverines in the wild twice, once in Glacier National Park and once in the Arctic National Wildlife Refuge. I wouldn’t say that they categorically avoid humans, but they are rare, they live in very rugged habitat, they cover tremendous distances, and they rarely stay in one place for very long, so they are difficult to observe. Yes, I still get excited every time I see a wolverine track, and following a wolverine trail in the snow is one of my favorite things to do. There is so much to learn from following an animal’s trail, step by step.
Q.Do you think the wolverine should be added to the endangered species list? Do others who study them think so?
A.I believe that the wolverine needs our help to survive for the long term. The Endangered Species Act is a tool to provide help to species in trouble, and I think that an E.S.A. listing would be a positive step for wolverine conservation. In the meantime, in the absence of a listing, biologists need to keep collecting data, and advocates and managers need to continue working to develop policies and management guidelines that will benefit wolverines.
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