Rare Sierra Nevada Red Fox Sighted
In Yosemite National Park
Yosemite National Park officials said a rare
Sierra Nevada red fox has
Sierra Nevada red fox has
been sighted in the park for the first time in
nearly 100 years.
nearly 100 years.
Yosemite officials say park wildlife biologists
had gone on a five-day
had gone on a five-day
backcountry trip to the far northern part of the
park to check on
park to check on
previously deployed motion-sensitive cameras.
They documented
They documented
a sighting of the fox inside the park on two
separate instances in
separate instances in
mid-December and on January 4.
The Sierra Nevada red fox of California is one
of the rarest
of the rarest
mammals in North America, likely consisting
of fewer than 50 individuals.
of fewer than 50 individuals.
"We are thrilled to hear about the sighting of
the Sierra Nevada
the Sierra Nevada
red fox, one of the most rare and elusive animals
in the Sierra
in the Sierra
Nevada,” said Don Neubacher, Yosemite National ParkSuperintendent,
in a news release. “National parks like Yosemite
provide habitat for all
provide habitat for all
wildlife and it is encouraging to see that the red
fox was sighted in the park.”
fox was sighted in the park.”
The Park says the nearest verified occurrences
of Sierra Nevada red
of Sierra Nevada red
foxes have been in the Sonora Pass area, north of
the park, where
the park, where
biologists from UC Davis, California Department
of Fish and Wildlife,
of Fish and Wildlife,
and the U.S. Forest Service have been monitoring
a small Sierra
a small Sierra
Nevada red fox population, first documented by
the USFS in 2010.
the USFS in 2010.
Prior to 2010, the last verified sighting of a
Sierra Nevada red fox in
Sierra Nevada red fox in
the region was two decades ago, according
to Yosemite officials.
to Yosemite officials.
“Confirmation of the Sierra Nevada red fox
in Yosemite National Park’s
in Yosemite National Park’s
vast alpine wilderness provides an opportunity
to join research partners
to join research partners
in helping to protect this imperiled animal,”
said Sarah Stock, Wildlife
said Sarah Stock, Wildlife
Biologist in Yosemite National Park. “We’re
excited to work across our
excited to work across our
boundary to join efforts with other researchers
that will ultimately give
that will ultimately give
these foxes the best chances for recovery.”
The Yosemite carnivore crew will continue to
survey for Sierra Nevada
survey for Sierra Nevada
red fox using remote cameras in hopes of
detecting additional individuals,
detecting additional individuals,
officials said Wednesday. At each camera
station, the crew also set up
station, the crew also set up
hair snare stations in the hopes of obtaining
hair samples for genetic analysis.
hair samples for genetic analysis.
Sierra Nevada red fox (Vulpes vulpes necator)
Threats
The Sierra Nevada red fox is distinguished from members of the introduced lowland population of red foxes by its slightly smaller size and darker colored fur. Red fox fur was sought after by trappers during the early part of last century because it was softer than California's grey fox. Sierra Nevada populations have been reduced by grazing in meadows, which reduces prey populations, and by trapping, logging, and recreational disturbances. Human activities of any significant degree in areas of core habitat will certainly put pressure on this highly endangered species. Given the low numbers of the Sierra Nevada red fox and the increase of non-native red fox population, particularly in the Central Valley of California, competition from this non-native species is increasingly a concern for the Sierra Nevada subspecies.
Habitat
The range of the Sierra Nevada red fox is limited to the conifer forests and rugged alpine landscape of the Sierra Nevada and Cascade ranges between 4,000 feet and 12,000 feet. Preferred habitat for the Sierra Nevada red fox appears to be red fir and lodgepole pine forests in the subalpine zone and alpine fell-fields of the Sierra Nevada. Open areas are used for hunting, forested habitats for cover and reproduction. Edges are utilized extensively for tracking and stalking prey. The red fox hunts in forest openings, meadows, and barren rocky areas associated with its high elevation habitats. Found mostly above 6,000 feet in the summer months, Sierra Nevada populations were historically found in a variety of habitats, including alpine dwarf-shrub, wet meadow, subalpine conifer, lodgepole pine, red fir, aspen, montane chaparral, montane riparian, mixed conifer, and ponderosa pine. Jeffrey pine, eastside pine, and montane hardwood-conifer also are used. This species is known to inhabit vegetation types similar to those used by the marten and wolverine. The range of the Red fox is from the northern California Cascades eastward to the northern Sierra Nevada and then south along the Sierran crest to Tulare County.
Conservation
The current range and distribution of Sierra Nevada red fox is unknown. Because of this and the scientific certainty of its hazardously low numbers, greater research is needed to ascertain the full extent of the red foxes range. Recent research conducted in the vicinity of Lassen Peak, has begun the process of understanding exactly how rare the native Sierra Nevada red fox is. This research conducted in the late 1990's estimated that only 10-15 individuals were likely present in the Lassen Peak area--a number certainly low enough to cause concern over the possibility of localized extinction and highly endangered status throughout its historic range. Other historical evidence related to the Sierra Nevada red fox has led scientists to believe that it likely never occurred in large numbers. From 1940 to 1959, 135 pelts were taken by trappers and that number shrunk down to 2 pelts a year by the 1970's. It is possible that red fox numbers were declining before these statistics were collected but in either case the Sierra Nevada red fox has certainly been in serious trouble for a very long time. The State of California banned red fox trapping in 1974.
Status
Until this summer (2010), the only known current population has been in the vicinity of Lassen Peak in Lassen Volcanic National Park, and also within Lassen National Forest. Periodic sightings have been reported by inexperienced observers throughout the rest of the Sierra Nevada but have not been documented by experts. In August, Forest Service biologists retrieved photographs from a bait station trail camera near Sonora Pass. DNA retrieved from saliva found on the tooth punctures in the bait bag was then analyzed by canid researchers Ben Sacks and Mark Statham at the UC Davis Veterinary Genetics Laboratory. Sacks and his colleagues confirmed that the DNA was from the rare Sierra Nevada red fox.
The Sierra Nevada red fox is genetically very distinct from red fox populations in coastal lowlands, the San Joaquin Valley and Southern California. These red foxes are derived from introduced foxes from the eastern United States (and Alaska). The Sacramento Valley subspecies is a genetically distinct native species, however.
The Sierra Nevada red fox is so uncommon that the California Fish and Game Commission declared it threatened in 1980 and it is considered critically endangered by the California Department of Fish and Game. The U.S. Forest Service, Pacific Southwest Research Station lists the Sierra Nevada red fox as a sensitive species.
According to a UC Davis press release, research from Sacks and his colleagues includes these findings to date:
- 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.
Scientific Research
Supporting Resources
California Department of Fish and Game Natural History Information (URL) --This California state website contains rather limited and old information but is a good basic background composite for the species. Choose from a drop-down list to select the animal you are interested in.
Fascinating--I never knew there was an endangered subspecies of red fox! Just more evidence to refute another of my pet peeves, that red foxes are NOT native to North America! A most beloved erroneous notion by MANY--often printed in textbooks and seen on documentaries! The basis for this notion is, of course, that British fox hunters brought the red fox from England, which they DID--they brought SOME to the eastern seaboard--, but what folks don't realize is that doesn't mean there weren't already red foxes in many places throughout North America(long enough to develop distinct subspecies, for crying out loud!)--the only question is WHERE exactly they were located--certainly in the Northern and Western parts of the continent. Red foxes ARE NOT an "invasive" species! Even if some bloodlines have a bit of Brit in their ancestry!....L.B.
ReplyDeleteall true L.B.............most recent peer reviewed data reinforces that red foxes were present in the east alongside gray foxes,,,,,,,,but likely not huge numbers as the forest favored gray foxes and their ability to climb trees...........as land was cleared, red foxes increased in numbers, supplemented by european introduction
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