By Michael Howell
The Bitterroot National Forest has been conducting backcountry surveys of small carnivores by placing bait in trees to attract them for a few years now. The bait stations are equipped with brass brushes to collect hair samples for DNA identification and automatic remote camera systems that snap photographs of the animals attracted to the sites. But this past winter the agency got a lot of help from a lot of people thanks to funds obtained by Defenders of Wildlife and a highly successful effort at rounding up citizen volunteers to set up and monitor close to two dozen sites across the forest. Other organizations that joined in the effort at recruiting volunteers for the project included the Montana Wilderness Association, Friends of the Bitterroot, the Selway-Bitterroot Frank Church Foundation, Bitterroot Audubon Society and the University of Montana.
According to Defenders of Wildlife Rockies and Plains Representative Kylie Paul, close to 160 volunteers signed up for the chance to participate in the wintertime survey and over 130 actually participated. Each site had a station leader with anywhere from five to eight volunteer helpers. They carried equipment and bait into the backcountry, set up the monitoring stations and checked on them every three to four weeks. The stations were monitored for four months starting in January. The bait stations were dismantled and removed and work was suspended at the end of April to avoid any potential conflict with bears coming out of hibernation.
Paul said that the number of people that responded to the call for volunteers was surprising and she was enormously pleased at the results.
“The information we were able to gather will be useful to the Forest Service in its ongoing efforts to monitor and document the activity of mesocarnivores on the forest,” said Paul. She said the data will provide a baseline that can be used over time to provide some very valuable information about the number and habits of the small carnivores using the forest.
A mesocarnivore is an animal whose diet consists of 50-70% meat with the balance consisting of non-vertebrate foods which may include fungi, fruits, and other plant material. The wolverine, for instance, is a mesocarnivore. Although it looks like a small bear, the wolverine is actually the largest member of the weasel family.
According to the National Geographic magazine, “Wolverines eat a bit of vegetarian fare, like plants and berries, in the summer season, but this does not make up a major part of their diet—they are tenacious predators with a taste for meat. Wolverines easily dispatch smaller prey, such as rabbits and rodents, but may even attack animals many times their size, such as caribou, if the prey appears to be weak or injured. These opportunistic eaters also feed on carrion—the corpses of larger mammals, such as elk, deer, and caribou. Such finds sustain them in winter when other prey may be thinner on the ground, though they have also been known to dig into burrows and eat hibernating mammals.”
Looking for information about the number of wolverines on the forest is of major interest to Defenders of Wildlife. On August 13th, the U.S. Fish and Wildlife Service (FWS) announced that wolverines will not be listed as threatened under the Endangered Species Act (ESA). But according to Defenders of Wildlife failure to protect the wolverine will inevitably lead to its extinction. They point to multiple threats that continue to jeopardize the wolverines’ fate into the future including the species’ extremely small population size, low genetic diversity, and direct and indirect adverse impacts from trapping, winter recreation, and habitat alteration. These threats are made worse by shrinking habitat from the loss of persistent snowpack across much of the West. According to the defenders, the USFWS now claims that the wolverine population is currently stable or increasing, yet there is no published research to show this is occurring. During the population’s low point in the 1900s, there were likely only a few individuals left in the Lower 48. Now, biologists estimate a total wolverine population of less than 300 individuals and an average effective population size (that portion of the population that contributes annually to the next generation) of only 35 animals.
Although the wolverine served as the poster child in the efforts to round up citizen volunteers a lot of information was also gathered about other mesocarnivores. According to US Forest Service wildlife biologist David Lockman, bait stations have provided evidence of Pine Martins, American Fishers, and Bob Cats, as well as wolverines. The only mesocarnivore of interest that was not detected on the forest recently is the Lynx. Lockman speculates that it may be related to the small number of snowshoe hares on the forest, a crucial part of the lynx diet. He said lynx were trapped on the forest in the 1970s and 1980s but since that time only a few reported sightings have been made but without any proof.
Aside from these animals, Lockman said that some foxes, coyotes and wolves seemed to approach the bait sites out of curiosity. Some birds are also attracted to the stations such as chickadees and stellar jays and occasionally a Golden Eagle. Mice and other small creatures will also sometimes set off the cameras at a station or sometimes just the wind in the trees.
“We are fortunate to have some of these rare animals, like the wolverine and the fisher on our forest here,” said Lockman. “To live where these animals roam wild is an amazing thing.”
The DNA gathered at the sites will help identify individual animals that may have visited multiple stations and this information together with the photographic information will be analyzed a private research company.
Rick Potts a member of the State Council of the Montana Wilderness Association who participated in the station monitoring this past winter called it “a wonderful example of Citizen Science.” He said it was a great experience to be out in the woods with people from all walks of life, from students to lawyers to carpenters, all out on the ground they share the forest with.
Both Potts and Paul hope to continue the volunteer monitoring program in the coming years.