THE SACRAMENTO VALLEY RED FOX
A small to medium-sized fox, with long and slender legs and pointed muzzle, and long brush-like tail. A large-sized and lankier subspecies of North American Red Fox. Pelage is dark dull rusty fulvous, becoming paler on sides. Throat and chest are white. Face dull fulvous, grizzled with whitish. Sides of nose dusky, grizzled with buffy. Muzzle slender and pointed, white on upper lip. Ears relatively large, pointed, erect, black backed, white inside. Black legs. Tail is relatively small, fulvous in color at base, becoming buffy whitish and profusely mixed with long black hairs, base with a black spot, and white tip. Females are smaller than males.
Reproduction and behavior
- Gestation: 61-63 days.
- Young per birth: 1-10.
- Weaning: 56-70 days.
- Sexual maturity: 12 months.
- Life span: 6 years.
- Breeding season: December and January.
Most births occur
in late February and early March. Den sites are closely associated
with grasslands and occur away from flooded agriculture, wetlands
and heavily urbanized areas. Den sites may be excavated ground
squirrel burrows, or located under sheds or woodpiles, in culverts,
road cuts, and between buildings. Social behavior: mated pairs are monogamous.
Diet and interaction with the environment
Their diet consists mainly in small mammals, berries, plants. The main predators are the coyote and the dogs. Gray Foxes affect the distribution and abundance of Sacramento
Valley Red Foxes, probably through exploitative competition,
resulting in exclusion from riparian areas or patches of dense
vegetation capable of providing refuge from Coyotes. However,
direct interference from coyotes is probably far more significant
than exploitative competition with Gray Foxes.
Habitat:
Native to United States, it is endemic to the Sacramento Valley, in California, occurring from Cottonwood to the Delta, west of the Sacramento River, and from Chico to Sacramento, East of the Sacramento River. Hybridization with introduced Red Foxes is found on the Southern and Southeastern margins of the range, possibly facilitated by low densities of native Foxes in these areas.
All Red Foxes south of the American River and Delta and West of the Sacramento Valley (Sonoma County), in lowland areas, are probably introduced Red Foxes, which derive largely from fur farm stock exhibiting ancestry from an admixture of diverse and phylogenetically distant sources.
Their habitat consists mostly in arid grasslands. They usually avoid flooded agriculture and wetlands, and heavily urbanized areas, which marks an important difference from non-native Red Foxes. They may use areas close to human structures if heavy cover is nearby.
Conservation status: It may qualify for threatened or endangered status. Anecdotal and genetic evidence suggest that this subspecies has declined considerably in abundance and range. While introgression occurs and could pose a greater threat in the future, some type of reproductive barrier with non-native Foxes appears to be in place.
Physiognomic information:
- Body length: 67.2 cm (♂), 65.2 cm (♀)
- Tail length: 41-42 cm
- Height: 35-45 cm
- Weight: 4.7 kg (♂), 4.0 kg (♀)
- Skull: 15 cm
Taxonomy:
The North American red foxes have been traditionally considered either as subspecies of the Old World red foxes, Vulpes vulpes, or subspecies of their own species, Vulpes fulva. Due to the opinion that North American red foxes were introduced from Europe, all North American red foxes have been seen as conspecific with Vulpes vulpes; however, genetic analyses of global red fox haplotypes indicates that the North American red foxes have been genetically isolated from the Old World populations for 400,000 years, prompting possible application of Vulpes fulva to all North American red foxes.
At least 9 subspecies are generally recognized in North America (Aubry, 1983 and 2009, Kamler and Ballard, 2002; Sacks, 2010): Vulpes fulva fulva (Eastern United States), Vulpes fulva rubricosa (central and E Canada), Vulpes fulva regalis, Vulpes fulva alascensis (boreal Alaska), Vulpes fulva abietorum (boreal Canada), Vulpes fulva macroura (Rocky Mountains), Vulpes fulva cascadensis (Cascade Range), Vulpes fulva necator (Sierra Nevada) and Vulpes fulva patwin (Sacramento Valley).
Castello (2018) has formalized treatment of Vulpes fulva as a separate species from the Old World Vulpes vulpes. In 2014, Mark J. Statham among others released a study that supports Vulpes fulva as a separate species from the Old World Vulpes vulpes. More about the Vulpes vulpes fulva and Vulpes fulva discussion:
The Sacramento Valley red fox is the last subspecies of North American red fox to be catalogued (in 2010), so there is little taxonomic information on this subspecies in many databases. You can read more info about this here and here.
Gallery:
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Due to the similarity in appearance between North American Red Foxes, some of the images may be erroneous. That's why I haven't found any videos about this subspecies either, if you think you have any image or video of the Vulpes fulva patwin let me know in the comments or contact me on any of my social networks (@etzharai).
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