Lycalopex vetulushoary fox

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)

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)

Physical Description

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)

  • Sexual Dimorphism
  • male larger
  • Range mass
    2.7 to 4 kg
    5.95 to 8.81 lb
  • Average mass
    3.33 kg
    7.33 lb
  • Range length
    585 to 640 mm
    23.03 to 25.20 in

Reproduction

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)

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)

  • Breeding interval
    Believed to breed once per year.
  • Breeding season
    These animals breed in the early fall.
  • Range number of offspring
    2 to 4
  • Average gestation period
    60 days

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.

Communication and Perception

Communication in hoary foxes is unknown, but is probably similar to other species of foxes.

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)

  • 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: 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)

  • Positive Impacts
  • body parts are source of valuable material
  • research and education
  • controls pest population

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 , et al., 1994; McDonald, 2001; McGlynn and Postanowicz, 2002; Nowak, 1999; Rylands, 1998)

Conservation 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

Nancy Shefferly (editor), Animal Diversity Web.

Erik Olson (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor), University of Wisconsin-Stevens Point.

Glossary

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

causes or carries domestic animal disease

either directly causes, or indirectly transmits, a disease to a domestic animal

chemical

uses smells or other chemicals to communicate

crepuscular

active at dawn and dusk

diurnal
  1. active during the day, 2. lasting for one day.
endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

fertilization

union of egg and spermatozoan

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

omnivore

an animal that mainly eats all kinds of things, including plants and animals

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

tactile

uses touch to communicate

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5? N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

References

Almeida, E., E. Moreira, L. Naveda, G. Herrmann. APR 2002. Combat of "Desmondus rotundus rotundus" (E. Geofroy, 1810) in the Cordisburgo and Curvelo carstic region, Minas Gerais, Brazil. Arquivo Brasilerio De Medicina Veterinaria Zootecnia, 54 (2): 117-126. Accessed 12/04.02 at http://www.webofscience.com/CIW.cgi.

Dalponte, J. 1997. Diet of the hoary fox, "Lycalopex vetulus", in Mato Grosso, Central Brazil. Mammalia, 61 (4): 537-546.

Eisenberg, J., K. Redford. 1999. Mammals of the Neotropics. Chicago and London: University of Chicago Press.

Lima , W., M. Guimaraes , I. Lemos . 1994. Occurrence of Angiostrongylus-Vasorum in the Lungs of the Brazilian Fox, "Dusicyon vetulus". Journal of Helminthology, 68 (1): 87-87.

MacDonald, D., O. Courtenay. JUN 1996. Enduring social relationships in a population of crab-eating zorros, "Cerdocyon thous", in Amazonian Brazil (Carnivora, Canidae). Journal of Zoology, 239: 329-355.

McDonald, D. 2001. The Encyclopedia of Mammals. New York: Barnes and Noble.

McGlynn, M., R. Postanowicz. 2002. "Hoary Zorro ("Dusicyon vetulus")" (On-line ). Lion Crusher's Domain. Accessed 10/02/02 at http://www.lioncrusher.com/animal.asp?animal=20.

Nowak, R. 1999. Walker's Mammals of the World. Baltimore and London: John Hopkins University Press.

Rylands, A. 1998. "Hoary Zorro ("Dusicyon vetulus")" (On-line ). Canid Species Accounts. Accessed 10/02/02 at http://www.canids.org/SPPACCTS/dvetulus.htm.

Travaini, A., J. Juste, A. Novaro, A. Capurro. 2000. Sexual dimorphism and sex identification in the South American culpeo fox, "Pseudalopex culpaeu", (Carnivora: Canidae). Wildlife Research, 27 (6): 669-674.

Wayne, R., S. O'Brien. 1987. Allozyme Divergance Within the Canidae. Systematic Zoology, 36 (4): 342: 339-355.