Naturalists are hoping that residents will report red fox sightings in the southern Sierra.
The rare animal was spotted for the first time since the 1920s the Humboldt-Toiyabe Forest in August.
Two more foxes were photographed within four miles of the previous sighting during the fall in the Stanislaus National Forest.
Scientists say the additional sightings indicate a genetically-unique population of Sierra Nevada red fox in the southern Sierra Nevada, rather than a single individual.
DNA taken from scat found near the new sighting indicated the fox is a male and could be related to the original female.
This red fox subspecies is one of the rarest, most elusive and least-known mammals in California and the United States, officials said.
Once widespread throughout California's mountains, the Sierra Nevada red fox has become very rare in recent decades, with only a single known population of fewer than 20 individuals in the Lassen region.
The U.S. Forest Service, the California Department of Fish and Game, the National Park Service, and researchers at both UC Davis and Cal Poly San Luis Obispo are working together to expand the survey effort to gain a better understanding of the distribution, population size, habitat relationships, and threats to this population of Sierra Nevada red fox, along with the Lassen population.
The Sierra Nevada red fox is a rare but essential part of the Sierra and Cascade mountain ecosystems in California. As a small carnivore preying on mice, squirrels, and hares, its food habits contribute to ecological balance. Due to its scarcity, the Sierra Nevada red fox was state-listed as threatened in 1980, and is a U.S. Forest Service sensitive species.
