Gray foxes are adept at climbing trees. They are active at night and during twilight, sleeping during the day in dense vegetation or secluded rocky places. Nursing mothers and pups use a den— a hollow log, abandoned building, tangle of brush, or cracked boulder—for shelter. When she is nursing small pups, the female stays within a few hundred meters of the den, but otherwise adults may range over a 2—5 square km area. Pups begin to forage on their own at about four months of age, and maintain close ties with the mother until they are about seven months old. By about ten months, both males and females are old enough to reproduce, and most females will have a litter annually from then on.

Links:
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The range of common gray fox extends from extreme southern Canada to northern
Venezuela and Columbia, excluding portions of the northern Rocky
Mountain region, the northern Great Plains, and eastern Central America
[16].  Common gray fox range has expanded in the last 50 years to areas
formerly unoccupied and areas where common gray fox had been extirpated
including New England, Michigan, Minnesota, Iowa, Ontario, Manitoba,
North Dakota, South Dakota, Nebraska, Kansas, Oklahoma, and Utah [9].

Ranges of subspecies follow [16].

U. c. borealis occurs in New England and southern Ontario.

U. c. californicus occurs from southwestern California to northern Baja
California.

U. c. cinereoargenteus occurs from southern Massachusetts and
Connecticut west to Lake Michigan and Illinois; south to central South
Carolina; and west to the Mississippi River.

U. c. floridanus occurs from southern South Carolina south to Florida
and west to eastern Texas; it occurs along the Gulf Coast excluding
Louisiana.

U. c. ocythous occurs in Wisconsin and extreme western Illinois; from
Missouri and Arkansas west to Oklahoma, Kansas, Nebraska, South Dakota,
North Dakota, and extreme southern Manitoba and Quebec.

U. c. scottii occurs from western Texas north through northern Colorado
and Utah to the southern half of Nevada; and from California east of the
Sierra Nevada southeast in Mexico to Chihuahua.

U. c. townsendi occurs in northern California and western Oregon.

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This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):

    1  Northern Pacific Border
    2  Cascade Mountains
    3  Southern Pacific Border
    4  Sierra Mountains
    6  Upper Basin and Range
    7  Lower Basin and Range
    9  Middle Rocky Mountains
   10  Wyoming Basin
   11  Southern Rocky Mountains
   12  Colorado Plateau
   13  Rocky Mountain Piedmont
   14  Great Plains

AL	AZ	AR	CA	CO	CT	DE	FL	GA	IL
IN	IA	KS	KY	LA	ME	MD	MA	MI	MN
MS	MO	NE	NV	NH	NJ	NM	NY	NC	ND
OH	OK	OR	PA	RI	SC	SD	TN	TX	UT
VT	VA	WV	WI	WY		MB	ON	PQ	MEXICO

Gray foxes occur throughout most of the southern half of North America from southern Canada to northern Venezuela and Colombia. They do not occur in portions of the mountainous northwestern United States, the Great Plains and eastern Central America.

Biogeographic Regions: nearctic (Native ); neotropical (Native )

The Grey Fox ranges from the southern edge of central and eastern Canada, and Oregon, Nevada, Utah and Colorado in the United States south to northern Venezuela and Colombia; and from the Pacific coast of the United States to the Atlantic and Caribbean oceans. The species is not found in the northern Rocky Mountains of the United States, or in the Caribbean watersheds of Honduras, Nicaragua, Costa Rica and western Panama.

Gray foxes are found in the lower half of the Nearctic and northwestern part of the Neotropics. More specifically, their range spans from southern Canada to Venezuela and Columbia, excluding portions of the Great Plains and mountainous regions of northwestern United States and eastern coast of Central America.

Biogeographic Regions: nearctic (Native ); neotropical (Native )

occurs (regularly, as a native taxon) in multiple nations

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: Oregon, Nevada, Utah, and Colorado in the west and the U.S.-Canadian border in the east, south through Mexico and Central America to northern Colombia and Venezuela (Wozencraft, in Wilson and Reeder 1993). See Steers (1979 COSEWIC report) for information on distribution in Canada.

Gray foxes resemble small, slender dogs with bushy tails. They are distinguished from most other Canidae by their gray upperparts, buff neck and black-tipped tail. Males are slightly larger than females. Gray foxes range from 800 to 1125 mm in length. Their tails measure 275 to 443 mm and their hindfeet measure 100 to 150 mm. They weigh 3.6 to 6.8 kg.

Range mass: 3.6 to 6.8 kg.

Range length: 800 to 1125 mm.

Sexual Dimorphism: male larger

Fully grown gray foxes display a mix of white, red, black and gray fur. However, new born pups tend to be dark brown. Gray foxes are medium-sized canids with elongated bodies and relatively short legs. They usually weigh between 3 and 5 kg, but can weigh up to 9 kg. Individuals at high elevation are slightly larger than their low elevation counterparts. Males are slightly larger than females, and skeletal measurements show that males have longer pelvises and calcanea, wider scapulae and more robust limb bones. In general, gray foxes can grow up to 1 m in length. Their tail makes up approximately one-third of their total body length and has a distinct black stripe along the dorsal surface and a black tip. The top of the head, back, sides, and rest of the tail are gray with the belly, chest, legs and sides of the face being reddish brown. The cheeks, muzzle and throat are white. Gray foxes have oval-shaped pupils and the area around the eyes has a thin black stripe from the outside corner of the eye to the side of the head. Additionally, a thick black stripe runs from the inside corner of the eye, down the muzzle to the mouth. They are sometimes misidentified as red foxes (Vulpes vulpes); however, red foxes have slit-shaped eyes, larger feet, longer legs, and a leaner body.

Range mass: 2 to 9 kg.

Range length: 800 to 1125 mm.

Average length: 1000 mm.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: male larger

Length: 113 cm

Weight: 5900 grams

Sexual Dimorphism: None

Length:
Range: 800-1,130 mm

Weight:
Range: 3-7 kg

More info for the term: cover

Common gray foxes tend to escape their enemies by finding cover rather than
depending on speed (as do red foxes) [23].  Dense vegetation is
important as diurnal resting and escape cover [18].  They climb trees
for use as resting and escape cover [23].  Their climbing ability
extends to saguaro (Carnegiea gigantea); one common gray fox was observed
resting 15 feet (4.6 m) above ground on a saguaro limb [6].

Den sites include hollow logs and trees, rock outcrops, underground
burrows (usually the abandoned den of some other species), cavities
under rocks, abandoned buildings, wood or sawdust piles, and brush
[9,23].  Dens have been found up to 20 feet (9.1 m) above ground in tree
hollows.  Underground dens have usually been excavated by animals of
other species, but common gray foxes occasionally dig dens in loose soil [35].

Den Use:  Dens are used throughout the year, but primary use is during
whelping season.  Dens are usually located in brushy or wooded habitats.
In Wisconsin most common gray fox dens were on east-, southeast-, or
south-facing slopes [9].  Leaves, grass, fur, and other soft materials
are added to dens [23].

More info for the terms: hardwood, shrub

Common gray foxes are most closely associated with deciduous forest,
particularly where it is in contact with disturbed or brushy habitat
[9,23,35].  They are usually found near surface water [29].  Preferred
habitat includes shrublands and brushy woodlands on hilly or rough
terrain.  In areas where common gray foxes and red foxes occur together, common gray
foxes prefer mixed woods with dense underbrush.  In the absence of red
foxes, common gray foxes prefer other habitats [35].

In New England common gray foxes are associated with dense northern hardwood or
mixed forests, thickets, and swamps.  Preferred habitat includes a
mixture of fields and woods [7].  In Wisconsin common gray foxes were most
abundant near brush-covered bluffs where woods and farmland were well
interspersed [28].  From Virginia to southern Georgia optimal common gray fox
habitat consists of woodland-farmland edge; post oak woodlands are also
good common gray fox habitat [9].  In southern Georgia common gray foxes are most
abundant in mixed woods and cultivated areas, less abundant in pine
savanna, and least common in mixed woods with dense underbrush [35].  On
the Coastal Plain most common gray fox captures occurred in tall
weed-broomsedge (Andropogon virginicus)-dominated habitats and
cultivated areas.  There were relatively few captures on forested sites;
this difference from common gray fox preferences in the majority of its range
was attributed to the absence of red foxes [24].

In the western states common gray fox habitats include rocky hillsides,
mountainsides, and washes [35].  In Oregon common gray foxes prefer mixed
hardwood and mixed conifer-hardwood habitats; they are present in
riparian hardwood, headland prairie, headland shrub, and tanoak
(Lithocarpus densiflorus) habitats [23].  In the Central Valley of
California, one common gray fox spent most of its time in old fields and
human-use areas, one spent most of its time in agricultural areas, and
two spent most of their time in riparian areas.  None of the foxes used
areas of open dirt [11].  In California common gray foxes were most abundant
from 3,800 to 5,000 feet (1,150-1,525 m) elevation [15].  In
northwestern California Douglas-fir forests, common gray foxes were present in
similar abundances in all forest seres, but there were slightly fewer
common gray foxes in mature timber [39].

Home Range:  Common gray foxes tracked from May through August, 1980 and
January through August, 1981, had a monthly average home range of 740
acres (299 ha), and an average composite home range of 1,700 acres (676
ha).  Some individuals occupied the same general area for extended
periods, but home ranges tended to shift from month to month.  Only a
fraction of the home range is used on a given night [18].  The composite
home ranges of four radio-tracked common gray foxes varied from 262 to 425
acres (106-172 ha).  Common gray foxes are apparently solitary in the
nonbreeding seasons [17].  In Wisconsin common gray fox home ranges vary from
0.24 to 1.2 miles (0.40-2 km) in diameter [32].  Lord [22] estimated
common gray fox home range diameter of 1.9 miles (3.2 km).  Trapp [34] reported
an annual home range average of 0.2 square mile (0.52 sq km).

Territoriality:  Common gray fox territoriality is not well defined.
Territories are marked with urine and feces, but in many areas home
ranges overlap considerably.  Family aggregates are formed so that
individual territories overlap; family aggregates do not overlap [18].

Common gray foxes occur in a wide variety of forest types; they prefer
woodlands and woodland-brush ecotones over open habitat.  They commonly
occur in eastern and southwestern deciduous forests, but are also found
in mixed and coniferous forests of the northeastern and western states [36].

Common gray foxes are ecologically important members of the oak (Quercus
spp.)-hickory (Carya spp.) ecosystem.  In the Missouri Ozarks mature
oak-hickory stands were the most frequently used (of six habitat types)
by common gray foxes, both at night and during the day.  Old fields were least
used [18].  In North Carolina common gray fox habitats include evergreen redbay
(Persea borbonia) forests, deciduous forests, and streamhead forests.
Common gray foxes were common in the most densely wooded habitats, including
pocosins.  They are often seen running along sandy rims and ridges
between bay and streamhead forests [5].  In central Louisiana common gray foxes
occur in longleaf pine (Pinus palustris)-slash pine (P. elliottii)
stands [25].  Common gray foxes are common in southwestern Wisconsin
oak-hickory forests dominated by white oak (Q. alba), northern red oak
(Q. rubra), black oak (Q. velutina), and shagbark hickory (C. ovata)
with lesser amounts of white ash (Fraxinus americana), green ash (F.
pennsylvanica), maples (Acer spp.), and basswood (Tilia americana) [33].

In Zion National Park, Utah, common gray foxes occur in blackbrush (Coleogyne
ramosissima), shrub-grassland dominated by fourwing saltbush (Atriplex
canescens), and pinyon (Pinus spp.)-juniper (Juniperus spp.) [35].  In
Texas common gray foxes are found in post oak (Q. stellata) woodlands,
pinyon-juniper woodlands, and wooded sections of shortgrass prairie.  In
western states common gray foxes are found in brushy habitat, woods, and
chaparral [36].  In Arizona common gray foxes are relatively rare; they are
typically found in pine (Pinus spp.)-Gambel oak (Q. gambelii) woodlands
at 5,000 to 6,000 feet (1,500-1,800 m) elevation.  They also occur in
pine-fir (Abies spp.), ponderosa pine (P. ponderosa), chaparral, and
desert grassland habitats [6,31].  In California common gray foxes are most
common in mature chaparral at elevations of 1,000 to 3,000 feet (300-900
m) and also occur in open chaparral, riparian areas, and other plant
communities [29].  In riparian zones they have been found in communities
dominated by Fremont cottonwood (Populus fremontii)-northern California
black walnut (Juglans californica var. hindsii), and by large willow
(Salix laevigata) [17].  In northwestern California common gray foxes were
present in Douglas-fir (Pseudotsuga menziesii) forests [39].

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This species is known to occur in association with the following Rangeland Cover Types (as classified by the Society for Range Management, SRM):

More info for the term: cover

   The common gray fox occurs in most SRM cover types.

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This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):

More info for the term: cover

   The common gray fox occurs in nearly every SAF cover type.

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This species is known to occur in association with the following plant community types (as classified by Küchler 1964):

More info for the term: association

   The common gray fox occurs in nearly every Kuchler plant association.

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This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):

FRES10 White-red-jack pine
FRES11 Spruce-fir
FRES12 Longleaf-slash pine
FRES13 Loblolly-shortleaf pine
FRES14 Oak-pine
FRES15 Oak-hickory
FRES16 Oak-gum-cypress
FRES17 Elm-ash-cottonwood
FRES18 Maple-beech-birch
FRES19 Aspen-birch
FRES20 Douglas-fir
FRES21 Ponderosa pine
FRES23 Fir-spruce
FRES24 Hemlock-Sitka spruce
FRES26 Lodgepole pine
FRES27 Redwood
FRES28 Western hardwoods
FRES29 Sagebrush
FRES30 Desert shrub
FRES31 Shinnery
FRES32 Texas savanna
FRES33 Southwestern shrubsteppe
FRES34 Chaparral-mountain shrub
FRES35 Pinyon-juniper
FRES36 Mountain grasslands
FRES37 Mountain meadows
FRES38 Plains grasslands
FRES39 Prairie
FRES40 Desert grasslands
FRES41 Wet grasslands
FRES42 Annual grasslands

Gray foxes are found in deciduous woodlands, but are occasionally seen in old fields foraging for fruits and insects. Unlike Vulpes vulpes, they do not prefer agricultural habitats.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: savanna or grassland ; forest ; scrub forest

Habitat and Ecology

Systems

• Terrestrial

Gray foxes prefer to live in deciduous forests interspersed with brushy, woodland areas. Many populations thrive where woodlands and farmlands meet; however, red foxes (Vulpes vulpes) are known to frequent agricultural areas more than gray foxes. Proximity to water is a key feature of preferred habitat as well. Dens are usually located in hollow trees or logs, in crevices between and under large rocks, and in underground burrows. Dens have also been found in the lower forest canopy, 10 m above the forest floor, in hollow tree trunks and limbs. Gray foxes are the only member of the Canidae family that can climb trees. They are most often found below 3000 m in elevation.

Range elevation: 1000 to 3000 m.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: savanna or grassland ; forest ; scrub forest

Comments: Often in woodland and shrubland in rough, broken country. Usually avoids open areas. May climb tree to avoid danger. Dens in cleft, small cave, hollow in tree or log, or debris pile; less frequently in burrow abandoned by other mammal.

Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

Common gray foxes are omnivorous, opportunistic feeders; they prey mainly on
small mammals, but fruit and invertebrates form a substantial portion of
the diet.  In the central United States cottontails (Sylvilagus spp.)
formed the major portion of the common gray fox winter diet.  Other mammals
taken in noticeable numbers include voles (Microtus spp.), mice
(Peromyscus spp.), woodrats (Neotoma spp.), and cotton rats (Sigmodon
spp.).  Invertebrates increase in importance in the spring.  With
seasonally advancing vegetative growth and development, plant material,
particularly fruit, increases in common gray fox diets, sometimes comprising up
to 70 percent by volume [10].  Grasshoppers (Orthoptera), beetles
(Coleoptera), and butterflies and moths (Lepidoptera) are the preferred
invertebrates; plant materials include fruits, nuts, grains, and
grasses.  Carrion is eaten opportunistically [35].  In some areas birds
(nestlings and eggs), particularly ground-nesters, are taken by common gray
foxes; in Texas wild turkey (Meleagris gallopavo) nests were broken up
by common gray foxes [3].

In a riparian area in the Central Valley of California, a common gray fox ate
mostly ring-necked pheasant (Phasianus colchicus), California ground
squirrels (Spermophilus beecheyi), California voles (Microtus
californicus), and berries [11].  In Oregon primary prey items include
mice, pocket gophers (Thomomys and Geomys spp.), kangaroo rats
(Dipodomys spp.), woodrats, ground squirrels (Spermophilus spp.),
chipmunks (Tamias spp.), brush rabbit (Sylvilagus bachmanii), and birds
including domestic poultry.  Other food items include grasshoppers,
beetles, manzanita (Arctostaphylos spp.) berries, juniper cones, and
cascara (Rhamnus purshiana) berries [23].  In the Sonoran Desert the
fruit of the California palm (Washingtonia filifera) forms a substantial
portion of the common gray fox winter diet [2].  In eastern Tennessee plant
foods included persimmon (Diospyros virginiana), black cherry (Prunus
serotina), blackberry (Rubus spp.) , and cancerroot (Conophilus
americana).  The most common vertebrate prey determined in scat analysis
(by volume) was eastern cottontail (Sylvilagus floridana), followed by
white-tailed deer (Odocoileus virginiana), presumably as carrion, and
rodents [14].

Gray foxes hunt alone and eat a wide variety of food. The most important food source for gray foxes is probably the Sylvilagus floridanus, but arvicolinae, Peromyscus, soricidae, and aves are readily captured and eaten. Gray foxes supplement their diet with whatever fruits are readily available and generally eat more vegetable matter than Vulpes vulpes.

Animal Foods: birds; mammals

Plant Foods: fruit

Gray foxes are omnivorous. Although they prey on small vertebrates, fruit and invertebrates also form a substantial part of their diet. Cottontails (Sylvilagus floridanus), mice (Peromyscus), woodrats (Neotoma), and cotton rats (Sigmodon hispidus) form the majority of their winter diet. In the Sonoran Desert, the fruit of the California palm makes up a significant portion of their winter diet. With the onset of spring, fruits become an increasingly important part of their diet, at times making up 70% of its diet. Invertebrates, fruits, nuts, and grains also increase in importance during the spring. Grasshoppers (Orthoptera), beetles (Coleoptera), and butterflies and moths (Lepidoptera) are the preferred invertebrates. When available, gray foxes may also feed on carrion. When gray foxes accumulate an excess amount of food, they cache it by digging a hole with their forepaws and burying it. Immediately afterwards, they mark it with urine or using their scent glands on their paws and tail in an effort to ward off other animals as well as to make it easier to relocate.

Animal Foods: birds; mammals; eggs; carrion ; insects; terrestrial non-insect arthropods

Plant Foods: roots and tubers; seeds, grains, and nuts; fruit

Foraging Behavior: stores or caches food

Primary Diet: carnivore (Eats terrestrial vertebrates, Insectivore , Scavenger ); herbivore (Frugivore , Granivore ); omnivore

Comments: Opportunistic omnivore. Often chiefly depends on rabbits and other small mammals in winter, insects and fruit in summer. Overall diet may be dominated by plant material in some areas.

Adult common gray foxes have few predators, but are occasionally taken by
golden eagle (Aquila chrysaetos), coyote (Canis latrans), and bobcat
(Lynx rufus) [35]; pups are taken by bobcat, great horned owl (Bubo
virginianus), and possibly large hawks [23].

Gray foxes impact their ecosystem as consumers of many different species of prey.

Large carnivores such as lynx canadensis, lynx rufus, and canis latrans may prey on gray foxes, but it has not actually been documented that this is the case.

Gray foxes have a small, but important role in our ecosystems. Their feeding habits allow them to influence small rodent (Rodentia) populations by maintaining a steady predator-prey relationship. They serve as a host to many parasitic arthropods, including fleas (Siphonaptera), lice (Phthiraptera), ticks (Ixodida), chiggers (Trombidiformes), and mites (Acari). Gray foxes are also host to a number of internal parasites including nematodes (Nematoda), flukes (Trematoda), tapeworms (Cestoda), and acanthocephalans (acanthocephala)

Commensal/Parasitic Species:

• nematodes (Nematoda)
• flukes (Trematoda)
• tapeworms (Cestoda)
• acanthocephalans (acanthocephala)
• fleas (Siphonaptera)
• lice (Phthiraptera)
• ticks (Ixodida)
• chiggers (Trombidiformes)
• mites (Acari)

Gray foxes primary predators include bobcats (Lynx rufus), golden eagles (Aquila chrysaetos), great-horned owls (Bubo virginianus) and coyotes (Canis latrans). In the southern region of the United States, gray fox abundance is highly dependent on coyote abundance. Other than death by natural causes, humans may be responsible for the greatest number of deaths and therefore may be their largest threat. Hunting, trapping and retaliatory killings by livestock ranchers are not uncommon. Unlike red foxes (Vulpes vulpes), which evade predators by using their superior agility, gray foxes escape by hiding under cover (e.g., brush piles). When escaping terrestrial predators, gray foxes can use their retractable claws to climb trees.

Known Predators:

• coyote (Canis latrans)
• bobcat (Lynx rufus)
• golden eagle (Aquila chrysaetos)
• great horned owl (Bubo virginianus)

Urocyon cinereoargenteus preys on:
Schismus barbatus
Cactaceae
seeds of other plants
mistletoe
Chaetodipus penicillatus
Columbidae
Carduelis
Toxostoma curvirostre
Carpodacus mexicanus
Calamospiza melanocorys
Amphispiza belli
Zonotrichia leucophrys
Sylvilagus
Neotoma
Dipodomys
cactus weevils
Moneilema
Oreoscoptes montanus
Turdus migratorius
Scorpiones
Araneae
carcass
Anas fulvigula
Anas acuta
Aix sponsa
Gallinula chloropus
Larus canus
Chordeiles minor
Neurotrichus gibbsii
Myotis grisescens
Tamias alpinus
Tamias merriami
Thomomys talpoides
Dipodomys californicus
Dipodomys deserti
Dipodomys venustus
Peromyscus boylii
Peromyscus polionotus
Microtus californicus
Microtus ochrogaster
Reithrodontomys megalotis
Zapus princeps

Based on studies in:
USA: Arizona, Sonora Desert (Desert or dune)
USA: New Mexico, Aden Crater (Carrion substrate)

This list may not be complete but is based on published studies.

More info for the terms: cover, shrub

Common gray foxes use brush and brushy woods in most areas.  Fire that reduces
brush cover will decrease common gray fox habitat.  Fire usually increases the
productivity of early successional prey species and improves predator
efficiency by reducing hiding cover for prey [21].  In the Southeast
fire produces immediate short-term habitat reduction for prey animals;
prey is concentrated in unburned habitat islands [19].  The most
important common gray fox prey in the Southeast are cottontails and cotton
rats.  Cottontails and cotton rats are not usually killed by fire but
prefer habitats with more cover than is found in immediate postfire
environments.  Both species return to postfire habitats when there is
sufficient vegetation for food and cover.  Fire often reduces fruit
production in the short term, but edges of older burns are usually good
regeneration sites for fruiting shrub species such as blackberries and
blueberries (Vaccinium spp.); gallberry (Ilex glabra) produces the most
fruit a few years after fire pruning [21].

More info for the terms: cover, litter

Diurnal Activity:  Common gray foxes are more active at night and at dusk than
during the day.  Activity levels decrease sharply at sunrise, and
increase at sunset [17,18].  Common gray foxes usually leave their daytime rest
area shortly before sunset, investigate the immediate area, and then
move purposefully to a foraging area.  Close to sunrise they usually
move back to a daytime resting area.  Common gray foxes usually change resting
sites every day once vegetative cover is abundant in late spring; sites
are reused in winter [17].

Breeding Season:  Common gray foxes usually breed from late winter to early
spring; dates of mating activity vary with latitude and elevation.  In
southern Illinois breeding occurs from late January to February; in
Wisconsin breeding occurs from late January to March [9], and in Oregon
mating occurs from mid-February to March [23].  Where common gray fox is
sympatric with red fox (Vulpes vulpes), common gray foxes breed 2 to 4 weeks
later than red foxes.  Common gray foxes are assumed to be monogamous, but
direct evidence is lacking [9].  There is only one litter per year [35].

Gestation and Development of Young:  Gestation periods have been
variously reported as ranging from 53 to 63 days; Fritzell [10] reported
gestation in captivity lasted 59 days.  Mean litter size is 3.8, ranging
from 1 to 7.  Development has not been well studied [9].  Young are born
blind and nearly naked.  Eyes open about 9 days after birth.  The pups
nurse for over 3 weeks.  Solid food is fed to the pups before they are
completely weaned with the male beginning to bring food to the pups at
about 2 to 3 weeks.  Pups begin to fend for themselves at about 3
months; families disperse in late summer and autumn [23].

Population Structure:  Root and Payne [33] determined that the majority
of animals in a southwestern Wisconsin common gray fox population were under 1
year old.  They concluded that common gray foxes are "an annual crop."  The
majority of female common gray foxes breed their first year [33].

Mortality and Longevity:  In the Central Valley of California, two of
four radiotracked common gray foxes were killed by cars [11].  In east-central
Alabama, a population of common gray foxes was tagged and monitored for causes
of mortality.  Canine distemper was the most frequent cause of death,
followed by trapping, automobile collision, and infectious canine
hepatitis.  Canine distemper was probably a localized cause of mortality
in this area; it is not expected that most common gray fox populations suffer
the same rate of distemper deaths [27].  Maser and others [23] stated
that collision with automobiles is rare in Oregon; the major causes of
common gray fox mortality are hunting and trapping.  They listed a probable
maximum longevity in the wild of 6 years.  The oldest captive common gray fox
lived less than 8 years [23].

Home range up to a few square miles in winter, less in summer (Richards and Hine 1953). Home ranges may or may not overlap. Probably reaches peak densities every 10 years. Probably averages around one family for every 4 square miles.

Like all Canidae, gray foxes have excellent senses of sight and smell. They most likely communicate with one another through scent marking, as do other dogs.

Communication Channels: chemical

Other Communication Modes: scent marks

Perception Channels: visual ; acoustic

Like other members of the family Canidae, gray foxes are able to communicate by barking and growling. Males have been observed trying to attract potential mates by raising their hind leg to show off their genitalia. As juveniles, gray foxes commonly play fight. As adults, they use their scent glands to mark territories and food sources.

Communication Channels: tactile ; acoustic ; chemical

Other Communication Modes: pheromones ; scent marks

Perception Channels: visual ; acoustic

Comments: Primarily crepuscular and nocturnal, but often active in daytime.

Gray foxes may live 6 to 10 years in the wild.

Range lifespan

Status: wild: 6 to 10 years.

Average lifespan

Status: captivity: 13.0 years.

Lifespan for both captive and wild gray foxes ranges from 6 to 8 years. However, the oldest recorded wild gray fox was 10 years old at time of capture, and the oldest captive gray fox lived to be 12 years old.

Gray foxes generally live for 6 to 8 years. The oldest wild gray fox was 10 years old when captured. The oldest gray fox in captivity lived to be 12 years old.

Range lifespan

Status: wild: 6 to 10 years.

Range lifespan

Status: captivity: 6 to 12 years.

Typical lifespan

Status: wild: 6 to 8 years.

Typical lifespan

Status: captivity: 6 to 8 years.

Maximum longevity: 16.2 years (captivity)

Gray foxes are monogamous; each has only a single mate.

Mating System: monogamous

The breeding season of gray foxes varies by location. In Michigan, gray foxes mate in early March; in Alabama, breeding peaks occur in February. Where vulpes vulpes and gray foxes occur together, gray foxes breed 2 to 4 weeks after the red foxes. Pregnancy lasts about 53 days; the average litter size is 3.8 and ranges from 1 to 7. By 3 months, pups begin to hunt with their parents. After four months, the young have their permanent teeth and can forage on their own. The family group remains together until autumn when the young reach sexual maturity and leave their parents.

Breeding interval: Grey foxes breed once per year.

Breeding season: The breeding season of grey foxes varies by location.

Range number of offspring: 1 to 7.

Average number of offspring: 3.8.

Range gestation period: 51 to 63 days.

Average gestation period: 53 days.

Range weaning age: 84 to 120 days.

Average time to independence: 6 months.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); fertilization ; viviparous

Average birth mass: 95 g.

Average number of offspring: 4.

Average age at sexual or reproductive maturity (male)

Sex: male: 365 days.

Average age at sexual or reproductive maturity (female)

Sex: female: 345 days.

Male and female gray foxes both provide protection for their offspring. Female gray foxes nurse their young until the young are able to hunt for themselves, when they are about four months old.

Parental Investment: altricial ; pre-fertilization (Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Male, Female); pre-independence (Protecting: Male, Female); extended period of juvenile learning

Gray foxes are solitary animals that socialize only during mating season. They are typically monogamous, although in rare cases polygamy and polyandry occur. For a short period of time after parturition, family groups consisting of male, female, and young exist. Male-female pairings form in the fall with breeding occurring in the winter. During October and September, attracting mates become more competitive and males usually display more aggression while retaining and defending mates. Similar to domestic dogs (Canis lupus familiaris), gray foxes have scent glands just inside the anus. Additional scent glands are found on their face and the pads of their feet. Although these glands are primarily used to demarcate territory, they may also be used to attract potential mates.

Mating System: monogamous

Breeding season varies with geographic region, elevation, and habitat quality. Breeding occurs in yearly cycles, beginning in January through late February, continuing into March. In some areas (e.g., Texas), breeding has been observed as early as December. Parturition occurs after about 2 months of gestation, peaking in April, with an average litter size of 3.8 pups, which weigh about 86 g at birth. Pups are typically weaned by 3 to 4 weeks, but may not be completely weaned until 6 weeks. Both genders are sexually mature by 10 months old, soon after dispersal. Annual onset of spermatogenesis occurs earlier and last longer than estrus. If they have been exposed to significant levels of the synthetic estrogen, diethylstilbestrol, females may experience delayed fertilization.

Breeding interval: Gray foxes breed once yearly.

Breeding season: December through March.

Range number of offspring: 1 to 7.

Average number of offspring: 3.8.

Range gestation period: 53 to 63 days.

Average gestation period: 59 days.

Range birth mass: 65 to 110 g.

Average birth mass: 86 g.

Range weaning age: 2 to 6 weeks.

Range time to independence: 10 to 17 months.

Average time to independence: 12 months.

Average age at sexual or reproductive maturity (female): 10 months.

Average age at sexual or reproductive maturity (male): 10 months.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); viviparous

Average number of offspring: 4.

Average age at sexual or reproductive maturity (male)

Sex: male: 365 days.

Average age at sexual or reproductive maturity (female)

Sex: female: 345 days.

Both genders take care of offspring in gray foxes. Before birth, males do a majority of the hunting, while females look for and prepare a suitable den. Weaning begins around 2 to 3 weeks of age. Pups begin eating solid food around 3 weeks old, which is primarily provided by the father. Parents teach pups how to hunt at around 4 months old. Until then, both parents prey for food separately, and pups practice their hunting skills by pouncing and stalking, which is primarily taught by the father. Pups depend on their parents for defense until about 10 months old, at which point they become sexually mature and disperse.

Parental Investment: precocial ; male parental care ; female parental care ; pre-hatching/birth (Provisioning: Male); pre-weaning/fledging (Provisioning: Male, Female, Protecting: Male, Female); pre-independence (Provisioning: Male, Female, Protecting: Male, Female)

Breeds mainly in winter. Gestation lasts 51-63 days (average 53). Parturition occurs in April or May in the south-central U.S. Litter size averages 3-5. Parturition occurs March-April. Weaned in 8-10 weeks. Sexually mature within 1 year.

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Specimens with Barcodes: 29
Species With Barcodes: 1

Information on state- and province-level protection status of animals in the
United States and Canada is available at NatureServe, although recent changes
in status may not be included.

Urocyon cinereoargenteus ocythous is Under Review for listing [40].

This species is currently not of any special conservation concern.

IUCN Red List of Threatened Species: least concern

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

Gray foxes are abundant throughout most areas in the lower two-thirds of North America. They have no special conservation status at this time. Although they are trapped and hunted by humans, there does not appear to be any immediate threat.

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

IUCN Red List of Threatened Species: least concern

Canada

Rounded National Status Rank: N3 - Vulnerable

United States

Rounded National Status Rank: N5 - Secure

Rounded Global Status Rank: G5 - Secure

Population

Population Trend

Major Threats

Hon [19] and Landers [21] suggest that in the Southeast, burning fields
and slash pine forests on 3-year rotations would create desirable
furbearer habitat; areas supporting fire-sensitive fruit-bearing plants
should be protected from fire.

Common gray fox pelts are of some value but are not as valued as those of red
fox [23].  Trapping increases and decreases with pelt values; in a 1987
report it was mentioned that sales in the United States had increased
dramatically in the last decade.  The common gray fox has "furbearer"
management status in many states [13,38].

Population Status:  The common gray fox is characterized by widespread, healthy
populations in most areas.  Habitat availability may limit its
distribution, but lack of habitat does not appear to pose an immediate
threat [13].  Common gray foxes are uncommon to common in New England [7].
Reported population densities range from 1 to 27 per square mile [35].

Common gray foxes are considered pests by many farmers who raise domestic
poultry; biologists claim that this damage is usually overstated and
that common gray foxes benefit agriculture by controlling rodent and rabbit
populations [23].  In northern bobwhite (Colinus virginianus) management
areas only a small number of common gray foxes (0.7%) were found to have
northern bobwhite remains in their stomachs [26].

Common gray foxes commonly carry rabies, most frequently in the Appalachian
states (KY, TN, VA, WV) [4].  They also carry tularemia [23] and canine
distemper which is not as virulent in common gray foxes as it is in domestic
dogs (Canis familiaris) [38].

Conservation Actions

Gray foxes will occasionally eat poultry and game birds, but they are not a serious threat to either.

Gray foxes are hunted primarily for sport as their pelts are not very valuable. The may help control populations of rodents that are damaging to agriculture or transmit disease.

Positive Impacts: controls pest population

Gray foxes are considered a problem species by poultry farmers. However, red foxes (Vulpes vulpes) are commonly misidentified as gray foxes, and commonly attack and kill poultry as well. In addition, gray foxes carry zoonotic diseases that could be a potential health threat to humans (e.g., rabies) and domestic dogs (Canis lupus familiaris; e.g., tularemia and canine distemper).

Negative Impacts: injures humans (causes disease in humans , carries human disease); causes or carries domestic animal disease

Gray foxes are hunted and trapped for their pelt. Compared to red fox (Vulpes vulpes), gray fox pelts are less desirable because the hairs are coarser and shorter. Gray foxes may also help control the abundance of certain agricultural pests, including rodents (Rodentia) and rabbits (Leporidae).

Positive Impacts: body parts are source of valuable material; controls pest population

Comments: Trapped for pelt.

Comments: Has been placed in the genus Canis or in the genus Vulpes by some authors (as recently as the 1970s). Urocyon cinereoargenteus and U. littoralis have been regarded as possibly conspecific by some authors; treated as distinct species by Jones et al. (1992) and Wozencraft (in Wilson and Reeder 2005).