High routes and the rare Sierra Nevada red fox

The Sierra Nevada red fox (SNRF) is a subspecies of red fox that has become genetically isolated since the retreat of the last ice age and is one of the rarest mammalian carnivores in North America.

High routes in the High Sierra — notably the Sierra High Route, Kings Canyon High Basin Route, and Yosemite High Route — pass directly through prime SNRF habitat:

• Subalpine parkland
• Subalpine meadows
• Alpine lakes, springs, and seeps
• Barren rock and talus

In Yosemite for the past decade, it’s only been detected above 9,000 feet.

This population is proposed for endangered status under the Endangered Species Act for fear of extinction. The SNRF population in Yosemite National Park and other nearby areas in the Sierra Nevada is extremely small with fewer than 76 individuals.

How high route hikers can help

Report sightings of the Sierra Nevada red fox to Yosemite Wildlife Ecologist, Sarah Stock ([email protected]). Photos and coordinates are helpful.

Of the thirty detections of the SNRF in Yosemite National Park since 2014, about three-fourths have been on or near the Yosemite High Route, making these hikers a potentially valuable source of data collection.

Identification

The key features that distinguish the red fox from the commonly seen coyote and gray fox are its white-tipped tail and black on the back of the ears. Coyote and gray fox have rusty colored ears and black-tipped tails.

While not a rule, red foxes often have “black socks” on their feet. Their tails are full and nearly the length of their body, while a coyote has a shorter tail, roughly a foot long.

Their fur is commonly reddish-orange but often comes in color morphs with various amounts of black (including nearly all black).

The graphics below were provided by Rocky Mountain Wild for the Colorado Corridors Project

Behaviors

The Sierra Nevada red fox is unlikely to be seen — there are few of them, and they are generally reclusive. However, they can quickly become habituated, as demonstrated by one SNRF that hung around Lee Vining for a couple of weeks, sleeping on back porches and lurking around the Epic Cafe. (Thankfully, he was traced back to northern Yosemite by the following summer, per DNA testing of scat.)

If you’re lucky enough to encounter a SNRF, please do not approach or attempt to feed it. Habituation could put the SNRF at risk of becoming dependent on human food or getting struck by a vehicle.

Human/fox conflicts

Biologists are uncertain if hikers have an impact on the movement of SNRF, but one park official told me that competition from coyotes (which also move to higher elevations in the summer) probably has “a much larger impact than human hikers.”

NPS does not believe that hikers affect the breeding season. By the time the retreating snow allows hikers to return to the alpine, the SNRF breeding season should be complete and the kits should be mobile.

Game cameras

Game cameras have been installed at several high passes that are part of the Sierra High Route, Yosemite High Route, and Kings Canyon High Basin Route by the National Park Service and other groups.

Please do not disturb these cameras or the nearby rock cairn. They are part of a monitoring effort studying the presence and distribution of SNRF.