In 2010, the U.S. Forest Service discovered another small group of foxes living near Sonora Pass, north of Yosemite National Park, Sacks said. Before that discovery, the last verified sighting near Yosemite was on the east side of the Sierra Nevada, near Tioga Pass, he said.
"We are thrilled to hear about the sighting of the Sierra Nevada red fox, one of the most rare and elusive animals in the Sierra Nevada," Don Neubacher, Yosemite National Park superintendent, said in a statement.
Sacks records red fox sightings online, and hopes the Yosemite news will encourage park visitors to dig through their vacation photos for images of the mysterious mammal. "There could be backpackers who have personal photos from the 1980s or 1990s," Sacks said. "Someone who has them might not have realized they were important enough to share."
Here's what to look for:
The Sierra Nevada red fox is smaller than Sierra Nevada red fox fur ranges in color from very red to black, but the fur behind its ears is always black. Coyotes and other fox species don't have this black fur behind the ears, Sacks said.
Red foxes have black fur on their legs, and coyotes don't.
Red foxes have big, fluffy, white-tipped tails. Coyotes can also have white-tipped tails, but relative to body size, a coyote tail is smaller than a Sierra Nevada red fox tail. "On a fox, the tail is almost as long as the body," Sacks said. "If a coyote is standing straight up, its tail might barely touch the ground, but a fox tail would be buried in the ground."
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