RENO, Nev. — The slender, bushy-tailed Sierra Nevada red fox will be listed as an endangered species, federal wildlife officials announced Monday, saying its population has dipped to just 40 animals in the area of California stretching from Lake Tahoe to the south of Yosemite National Park.
The U.S. Fish and Wildlife Service decided against listing a distinct population of the foxes in the southern Cascade Range of Oregon and near Lassen Peak in Northern California.
But it said in a listing rule to be published in the Federal Register on Tuesday that the Sierra Nevada segment south of Tahoe “is in danger of extinction throughout all of its range.”
“While the exact number remains unknown and is also subject to change with new births and deaths, it is well below population levels that would provide resiliency, redundancy, and representation to the population.”
It provided no estimate of the number of red foxes remaining in the Cascade Range.
One of the rarest mammals in North America, the red foxes in the Sierra already are vulnerable due to threats of wildfire, drought, competition in coyotes, reductions in prey, and inbreeding with non-native foxes.
Additional future threats include climate change, as scientists project continuing loss of snowpack and of the general subalpine habitat to which the Sierra Nevada population segment has adapted, the agency said.
The service said that this will likely lead to increased numbers of coyotes in high-elevation areas and to increased competition between coyotes and the Sierra Nevada foxes for prey.
Some biologists believed 20 years ago, the Sierra Nevada population already had gone extinct before a small remnant population was confirmed in 2010. California banned red fox trapping in 1974.