February 23, 2020 - This winter, Yosemite biologists confirmed that at least one fisher continues to live in forested habitat north of the Merced River in Yosemite National Park. Using motion-sensored cameras, scent-detecting dogs, and genetic analysis, biologists confirmed two fisher scats and four fisher pictures, comprising one to six individuals.
In 2017, a fisher was detected north of the Merced River for the first time in almost 100 years. Biologists collared and tracked the animal to study its habitat needs, but after the collar battery died soon thereafter, the fate of the fisher became a mystery. We hope to learn through DNA genotyping if any of the recent detections match the DNA of the fisher that was captured and collared in 2017.
Yosemite comprises the northern extent of the southern Sierra Nevada fisher population and these detections extend their range farther north into Yosemite than previously thought. The fisher is a very rare and secretive member of the weasel family, and its population in the southern Sierra is proposed for federal listing. Biologists in Yosemite are committed to learning more about the park's fisher population and how the park can ensure their continued survival, in spite of increased tree mortality and large landscape-level fires. This fisher research is a collaboration between Yosemite National Park, US Forest Service, Rogue Detection Dog Teams, U.C. Davis, and Oregon State University.
Source: NPS
