By Erik Olson
Geographic Range
Hoary foxes, Lycalopex vetulus, live in the neotropical region of the world. They are found in the Minas Gerais and the Motto Grosso regions in southwestern Brazil. (Eisenberg and Redford, 1999; Rylands, 1998)
Biogeographic Regions:
neotropical
(native
).
Habitat
Hoary foxes live in tall grass steppes and in savanna interspersed with wooded "islands", as well as upland mountain areas in open woodland and brushland. Their habitat extends across the more open terrain of east-central Brazil. They live near cerrado vegetation. (Eisenberg and Redford, 1999; McGlynn and Postanowicz, 2002; Rylands, 1998)
These animals are found in the following types of habitat:
terrestrial
.
Terrestrial Biomes:
savanna or grassland
; forest
; scrub forest
; mountains
.
Physical Description
(5.94 to 8.8 lbs; avg. 7.33 lbs)
(23.03 to 25.2 in)
Hoary foxes are small, with a short muzzle and small teeth. Their fur is grayish in color, with a pale underbody and reddish ears and legs. There is a dark stripe running along the dorsal line and the tip tail. The exterior of the legs is yellow, and there is a black spot above the tail gland. The word "hoary" means having white or silvery color, which refers to the white hairs in the otherwise gray coat of these animals. The fur is short. (Eisenberg and Redford, 1999; McGlynn and Postanowicz, 2002; Rylands, 1998; Travaini et al., 2000)
Hoary foxes have a small skull, with reduced carnassials and broad molars. Total body length is approximately 60 cm, with an average tail length of about 32 cm. Adult body weights range from 2.7 to 4 kg. (Eisenberg and Redford, 1999; McGlynn and Postanowicz, 2002; Rylands, 1998; Travaini et al., 2000)
A closely relatd species, L. culpaeus, shows a positive, slight sexual dimorphism, with males being 5% larger than females. This is comparible to values reported for other foxes. Although such dimorphism has not been reported for L. vetulus, this evidnece suggests that slight sexual dimorphism in hoary foxes exists. (Eisenberg and Redford, 1999; McGlynn and Postanowicz, 2002; Rylands, 1998; Travaini et al., 2000)
Some key physical features:
endothermic
; homoiothermic; bilateral symmetry
.
Sexual dimorphism:
male larger.
Reproduction
Believed to breed once per year.
These animals breed in the early fall.
This species is monogamous, as are many fox species. (Eisenberg and Redford, 1999; MacDonald and Courtenay, JUN 1996; McDonald, 2001; Wayne and O'Brien, 1987)
Mating systems:
monogamous
.
Breeding occurs in early fall. The gestation period is about two months, after which time the female gives birth to a litter of 2 to 4 kits. Hoary foxes often use abandoned armadillo dens for rearing their pups. (Eisenberg and Redford, 1999; McGlynn and Postanowicz, 2002; Rylands, 1998)
Key reproductive features:
iteroparous
; seasonal breeding
; gonochoric/gonochoristic/dioecious (sexes separate); sexual
; fertilization
; viviparous
.
Parental care in this species is not well documented. However, as is the case with most canids, the young are likely to be altricial. They are born in the den and remain there until they are able to venture out on their own. The mother undoubtedly provides her young with milk, grooming, and protection. Although the role of the father has not been documented for this species, in many other foxes, pups are cared for by both males and females. Because this species is monogamous, it is likely that the male plays some role in caring for the young. (MacDonald and Courtenay, JUN 1996; Wayne and O'Brien, 1987)
Parental investment:
no parental involvement; altricial
; pre-fertilization (protecting: female); pre-hatching/birth (provisioning: female, protecting: female); pre-weaning/fledging (provisioning: female, protecting: female); pre-independence (provisioning: male, female, protecting: male, female).
Lifespan/Longevity
Hoary fox lifespans have not been recorded.
Behavior
Hoary foxes are usually timid, but will aggressively defend their young. They normally use armadillo burrows for dens and are usually diurnal, but are often active at night and during twilight. (Eisenberg and Redford, 1999; McDonald, 2001; McGlynn and Postanowicz, 2002; Nowak, 1999; Rylands, 1998)
Behavior in related species suggests that hoary foxes are territorial. Parents often travel with their adult sized offspring, and conflict over territory arises between parent and offspring during the dry season. (MacDonald and Courtenay, JUN 1996)
Home Range
Home range size is unkown.
Key behaviors:
cursorial; terricolous; diurnal
; nocturnal
; crepuscular
; motile
; sedentary
; territorial
; social
.
Communication and Perception
Communication in hoary foxes is unknown, but is probably similar to other species of foxes.
Other communication keywords:
scent marks
.
Food Habits
Hoary foxes are omnivores, but they appear to be termite specialists. Termites of the genus Syntermes are their main food source and is found in about 89.5% of its feces. They feed on this termite year round. The other foods eaten by hoary foxes include rodents, fruit, grasshoppers, and dung beetles. (Dalponte, 1997; Eisenberg and Redford, 1999; McDonald, 2001; McGlynn and Postanowicz, 2002; Nowak, 1999; Rylands, 1998)
The diet of L. vetulus varies seasonally. Termites and small mammals make up the majority of their diet during the dry season, and other insects and fruit make up the majority during the wet season. The unique dental structure of this species allows these animals to eat small items. Their reduced carnassials and broad molars are good for crunching up an insectivorous diet. (Dalponte, 1997; Eisenberg and Redford, 1999; McDonald, 2001; McGlynn and Postanowicz, 2002; Nowak, 1999; Rylands, 1998)
Physical features of hoary foxes suggest adaptation to its habitat. A food niche separation mechanism between this species and other wild canids in that region has probably caused the dietary shift in this species to termites, as well as their small muzzel and dentition. (Dalponte, 1997; McDonald, 2001; McGlynn and Postanowicz, 2002; Nowak, 1999; Rylands, 1998)
Primary Diet:
omnivore
.
Animal Foods:
birds; mammals; reptiles; insects; terrestrial non-insect arthropods.
Plant Foods:
fruit.
Predation
There is little information on predation of hoary foxes. However, it is parasitized by the vampire bat, Desmodus rotundus. It should be noted, however, that these bats do not kill the animals upon which they feed, so it isn't a predator in the traditional sense. (Almeida et al., APR 2002)
Ecosystem Roles
Hoary foxes are generalist predators. They affect populations of small rodents and termites. (Eisenberg and Redford, 1999)
Economic Importance for Humans: Negative
Hoary foxes are hosts for many diseases, some of which can be transmitted to domestic dogs, and some to humans. Also, hoary zorros are suspected of killing poultry and are therefore hunted. (Almeida et al., APR 2002; Lima, Guimaraes, and Lemos, 1994; McDonald, 2001; McGlynn and Postanowicz, 2002; Nowak, 1999; Rylands, 1998)
Ways that these animals might be a problem for humans:
injures humans (carries human disease); causes or carries domestic animal disease
.
Economic Importance for Humans: Positive
Close relatives of the hoary fox are fur-bearers, and pelts of this species are likely collected as well. In addition, these animals are sometimes found in zoos. (McGlynn and Postanowicz, 2002; Rylands, 1998; Travaini et al., 2000)
Ways that people benefit from these animals:
body parts are source of valuable material; research and education; controls pest population.
Conservation Status
IUCN Red List: [link]:
Data Deficient.
US Federal List: [link]:
No special status.
CITES: [link]:
No special status.
Hoary foxes are listed as data deficient by IUCN. Changes in agricultural practices may result in habitat loss. Deforestation and hunting are also threats to this species. (McDonald, 2001; McGlynn and Postanowicz, 2002; Nowak, 1999; Rylands, 1998)
Other Comments
Hoary foxes have many common and scientific names such as, small-toothed dog, Lycalopex vetulus, Pseudalopex vetulus, and Dusicyon vetulus. (Dalponte, 1997; Eisenberg and Redford, 1999; McGlynn and Postanowicz, 2002; Rylands, 1998)
Contributors
Erik Olson (author), University of Wisconsin-Stevens Point.
Chris Yahnke (editor), University of Wisconsin Stevens Point.
Nancy Shefferly (editor), Animal Diversity Web Staff.

