Chrysocyon brachyurusmaned wolf

Geographic Range

The maned wolf is distributed from the mouth of the Parnaiba River in northeastern Brazil west to the Pampas del Heath in Peru and South through the Chaco of Paraguay to Rio Grande do Sul, Brazil. Its former range included parts of Uruguay and Argentina.

Habitat

Chrysocyon brachyurus is found in grassland, savanna, dry shrub forest, swampy areas, forest-edge habitat, and river areas.

Physical Description

Chrysocyon brachyurus is a stunning animal. The largest of all South American canids, it stands almost one meter tall at the shoulder and has a long, golden-red coat. Head and body length ranges from 1245 to 1320mm and tail length from 280 to 405mm. The long thin legs, which may serve to help the maned wolf to see above tall grass, grade from red to black at their lower portions. The anterior part of the erectile mane of long hairs is black as well. The body is narrow and the ears large and erect. The dentition of the maned wolf reflects its food habits. As this animal does not kill or eat large prey, its upper carnassials (shearing teeth) are reduced, its upper incisors weak, and its canines are long and slender.

  • Range mass
    20 to 23 kg
    44.05 to 50.66 lb

Reproduction

Maned wolves are monogamous, though males and females tend to live independently except during the breeding season.

Little is known about the reproductive patterns of wild maned wolves. Females are monoestrous. Breeding season is probably controlled by photoperiod; captives copulate between October and February in the Northern Hemisphere and between August and October in South America. The estrous lasts for a period of one to four days. Gestation in captivity is similar to that of other canids and lasts approximately 65 days. A litter usually contains one to five young. A record number of seven has been observed. Young are born weighing 340 to 430 grams and develop quickly. Their eyes and ears open by day nine, their ears stand upright and they will take regurgitated food by week four, the pelage changes from black to red by week ten, they are weaned by 15 weeks, and their bodies have the proportions of adults at one year, at which time they reach sexual maturity. Captive individuals have lived 15 years. Non-captive maned wolves give birth in natal nests hidden by thick vegetation. Wild maned wolves are rarely seen with their pups.

  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual
  • Range number of offspring
    1 to 5
  • Average number of offspring
    2.47
  • Average number of offspring
    3
    AnAge
  • Range gestation period
    56 to 66 days
  • Range weaning age
    120 to 210 days
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    730 days
    AnAge

Lifespan/Longevity

Behavior

Maned wolves are primarily nocturnal and have crepuscular activity peaks. Field studies have shown that males are generally more active than females. During the daylight hours these canids rest in areas of thick brush cover and infrequently move short distances. The basic social unit of Chrysocyon brachyurus is the male-female mated pair. These animals share a permanent home range (on average 27 square kilometers) but remain fairly independent of one another. They hunt, travel, and rest solitarily, and are only closely associated during the breeding season. Boundaries between territories are strictly observed; neighboring pairs remain on their respective sides. Urine and feces, deposited regularly in particular spots, may serve to mark territories. Nomadic males skirt the edges of boundaries and replace males removed by death or capture.

In captivity, opposite-sex pairs fare more successfully than same-sex pairs. The latter fight initially, then quickly establish a dominance hierarchy. Mated pairs associate more than wild mated pairs do; they may groom one another and rest and feed together. Captive fathers demonstrate quite a bit of parental care. They help females during partruition and participate in the grooming, food provisioning and defense of the young. Captive littermates begin to establish a dominance hierarchy by the age of one month.

Maned wolves emit three types of vocalization. One is a single deep-throated bark that is often heard after dusk, another a high-pitched whine, and the last a growl heard during agonistic behavior.

Communication and Perception

Food Habits

The maned wolf is omnivorous. It eats armadillos, rabbits, rodents and other small mammals, fish, birds, bird eggs, reptiles, gastropods and other terrestrial mollusks, insects, seasonably available fruits, and other vegetation. Fruits taken include bananas, guavas, and primarily the tomato-like Solanum lycocarpum. (S. lycocarpum may provide medicinal aid against Dioctophyme renale, a worm that infects the kidneys of the maned wolf). Vegetation eaten is often in the form of roots and bulbs. Vertebrate prey do not often include large domestic stock, but an occasional newborn lamb or pig is taken by Chrysocyon. The maned wolf, much to the dislike of poultry farmers, frequently feeds upon free-ranging chickens. It stalks and pounces in a fox-like manner upon its animal prey.

  • Animal Foods
  • birds
  • mammals
  • reptiles
  • fish
  • eggs
  • insects
  • mollusks
  • Plant Foods
  • roots and tubers
  • fruit

Economic Importance for Humans: Positive

The maned wolf eats crop pests such as rabbits and small rodents.

Economic Importance for Humans: Negative

As mentioned above, the maned wolf takes domestic poultry and the occasional lamb or newborn pig.

Conservation Status

Chrysocyon brachyurus is listed as CITES Appendix II, U.S. ESA-Endangered, and IUCN-Vulnerable. Habitat destruction (including the annual burning of its grasslands), persecution by angry poultry farmers, hunting for sport, and live capture are factors that threaten the maned wolf. This animal disapeared from Uruguay in the 19th Century. Its former range also included parts of Argentina south of the La Plata River.

Other Comments

Although the maned wolf displays many fox-like characteristics, it is not closely related to the foxes and lacks the elliptical pupils found in the vulpine canids. Some believe that it is closely affiliated with Dusicyon, but electrophoretic studies do not link Chrysocyon with any of the other canids studied. This implies that the maned wolf may be the only survivor of the late Pleistocene extinction of the large South American canids. The maned wolf's natural history and its evolutionary relataionship to the other members of the canid family make it a unique animal; drastic efforts to conserve it are warranted. Fossils of the maned wolf from the Holocene and the late Pleistocene have been excavated from the Brazilian Highlands.

Contributors

Antonia Gorog (author), University of Michigan-Ann Arbor.

Glossary

Neotropical

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

World Map

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.

chemical

uses smells or other chemicals to communicate

crepuscular

active at dawn and dusk

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.

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

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

scrub forest

scrub forests develop in areas that experience dry seasons.

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.

solitary

lives alone

tactile

uses touch to communicate

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.

References

Dietz. J.M. (1985). Mammalian Species, No. 234, American Society of Mammalogists. pp 1-4.

Macdonald, David. (1984). The Encyclopedia of Mammals, Facts on File Publications, New York, pp 82-83.

Nowak, Ronald M., and Paradiso, John L. (1983). Walker's Mammals of the World, Vol. 2, Fourth Edition, The Johns Hopkins University Press, Baltimore and London, pp 957-958.

Sheldon, Jennifer W. (1992). Wild Dogs: The Natural History of the Nondomestic Canidae, Academic Press Inc., San Diego, California, pp 69-75.