Sierra Nevada Red Fox shows up in a California location that has not seen the species for 90 years!

 

Staff Reports 

Scientists find red fox thought extinct from Sonora Pass region

The Forest Service today announced the recent sighting of a Sierra Nevada red fox, in the area where the Humboldt-Toiyabe and Stanislaus National Forests and Yosemite National Park come together.

This summer, the Forest Service has been conducting monitoring activities with motion sensitive cameras to detect the presence of the elusive fisher and pine martin, two forest carnivores known to frequent the High Sierra.

While checking photographs on Aug. 11, Forest Service wildlife biologists Sherri Lisius, from the Humboldt-Toiyabe National Forest, and Adam Rich, from the Stanislaus National Forest, identified a photo believed to be that of a red fox. Surprised by what they saw, the Forest Service biologists consulted with California Department of Fish and Game. The only known population of Sierra Nevada red fox occurs in the Lassen Peak region – about 150 miles to the north.

Recent survey efforts by CDFG in the Sierra Nevada have failed to detect red foxes south of the Lassen area, making the Forest Service detection significant.

"The last known sighting of a Sierra Nevada red fox in the Sonora Pass area was sometime in the 1920s," said Mike Crawley, Bridgeport District Ranger. "Needless to say, we are quite surprised and excited by this find."

The Sonora Pass population of the Sierra Nevada red fox carried a genetic signature seen previously only in museum specimens collected before 1926. Analysis of hair found on the tree supporting the motion sensitive camera allowed UC Davis veterinary geneticists to identify it as originating from a Sierra Nevada red fox, distinct from the Lassen Peak population.

Wildlife biologists from the Forest Service, CDFG, and the University of California, Davis, will set-up additional monitoring stations to gather more information on the presence of Sierra Nevada red fox in the area of Sonora Pass. Learn more about this release by contacting Humboldt-Toiyabe National Forest Public Affairs Officer, Christie Kalkowski, at 775-355-5311.

 

 

Fox spit helped Forest Service confirm rare find

September 3, 2010

Three weeks ago, when U.S. Forest Service biologists thought they had found a supposedly extinct fox in the mountains of central California, they turned to UC Davis for confirmation.

Photographs taken by a Forest Service trail camera in Sonora Pass seemed to show a Sierra Nevada red fox (Vulpes vulpes necator) biting a bait bag of chicken scraps. That would be an amazing discovery, since no sighting of that species has been verified south of Mount Lassen, 200 miles away, since the mid-1990s.

The biologists shipped the bait bag to wildlife genetics researchers Ben Sacks and Mark Statham at the UC Davis Veterinary Genetics Laboratory. Since 2006, they have radically altered our understanding of red foxes in California, supplying information crucial to conservation efforts.

Sacks and Statham scraped saliva from the tooth punctures on the bag and analyzed the DNA within. Before you could say spit, they had the answer: definitely a Sierra Nevada red fox.

"This is the most exciting animal discovery we have had in California since the wolverine in the Sierra two years ago -- only this time, the unexpected critter turned out to be home-grown, which is truly big news," Sacks said. (The wolverine was an immigrant from Wyoming).

Four years ago, Sacks began analyzing California red fox DNA collected from scat, hair and saliva from live animals, and skin and bones from museum specimens. Until then, the expert consensus was that any red fox in the Central Valley and coastal regions of the state was a descendant of Eastern red foxes (V.v. fulva) brought here in the 1860's for hunting and fur farms.

Sacks and his colleagues have confirmed that red fox populations in coastal lowlands, the San Joaquin Valley and Southern California were indeed introduced from the eastern United States (and Alaska). But they have also shown that:

• There are native California red foxes still living in the Sierra Nevada.
• The native red foxes in the Sacramento Valley (V.v. patwin) are a subspecies genetically distinct from those in the Sierra.
• The two native California subspecies, along with Rocky Mountain and Cascade red foxes (V.v. macroura and V. v. cascadensis), formed a single large western population until the end of the last ice age, when the three mountain subspecies followed receding glaciers up to mountaintops, leaving the Sacramento Valley red fox isolated at low elevation.

Sacks' extensive research program focuses on canids, especially red foxes (evolution, ecology and conservation) and dogs (genetics, geographic origins and spread). He and his students also are working on other carnivores, including disease ecology and interactions among fishers, bobcats, coyotes and gray foxes, and population genetics of ringtails and coyotes.