Kylie Paul, Rockies and Plains Representative
Oddly enough, fishers don’t eat fish. Instead, these solitary and highly elusive members of the weasel family prey on creatures such as showshoe hare, porcupine and other small animals. Fishers’ pre-European distribution ranged across the boreal forests of Canada, extending south into the United States in the Great Lakes area and along the Appalachian, Rocky and Pacific Coast Mountains. But their luxurious coasts made them a highly sought-after furbearer in the 1800s, leading to dramatic reductions in range and population. While their populations have grown throughout many northern forests in North America, there is still little information on their distribution and population status in the Rockies. Some biologists think they are the most imperiled predator in the northern Rockies, but it is hard to know for sure without more data. Earlier this year, Defenders participated in a program incorporating citizen volunteers and DNA sampling to better understand the distribution of these important creatures.
Given the relative lack of information available on the prevalence and habits of fishers, they have sparked a significant amount of curiosity and debate. Defenders petitioned the U.S. Fish and Wildlife Service to provide Endangered Species Act protections to fishers in the U.S. northern Rockies, and in 2010, the Service announced that our petition raised legitimate concerns and it would consider listing fishers in the northern Rocky Mountains. However, the agency held off after deciding there was insufficient data to show their population in the region has declined historically.
To fill this data hole, researchers at the U.S.Forest Service (USFS) Rocky Mountain Research Station began monitoring fishers in 2007. They sample five-mile-square grids and place hair snares in likely fisher habitat within those grids to collect hair (and thus DNA) for genetic analyses. A hair snare is a triangular tube made of waterproof posterboard, similar to the kind used for real estate signs. Each side has bristle rifle brushes, and in between those brushes is an enticing raw chicken wing. Anything that wants the chicken has to squeeze past the brushes, leaving a few hairs in the bristles. DNA from these hairs is then used to identify species and individuals in a lab. In addition to being painless for the fishers, this relatively easy standardized protocol allows ordinary citizens to assist in the surveys.
The U.S. Forest Service partnered with such citizen volunteers to set up and retrieve fisher hair snares along Forest Service roads and trails throughout the Ninemile Watershed/Ranger District of Lolo National Forest in Montana. Earlier this fall, 13 citizen volunteers were trained and, working in pairs, set out more than 70 hair snares in possible fisher habitat within grids in the Ninemile. Three weeks later, more volunteers headed to those same snares to remove them and gather hair samples. I took part in the hair snare survey, and hope to be able to with with the USFS on similar efforts in the future.
Preliminary results of the hair snare DNA analyses showed that no fishers were detected in the Ninemile this past September. Other species whose hair was found in the snares included striped skunk, bushy tailed woodrat, snowshoe hare, red squirrel, northern flying squirrel, coyote and pine marten. While fisher weren’t detected with this survey, it doesn’t necessarily mean they do not exist there — it could mean that we just didn’t find them, and we may want to try again.
One thing is clear: this was a win-win for citizens and fishers alike. It allowed volunteers to get involved in wildlife work while also providing an opportunity to learn more about the distribution of these fascinating creatures.