The Fox on Stilts

Chrysocyon brachyurus - The Maned Wolf

Source: Wikimedia Commons

Kingdom: Animalia

Phylum: Chordata

Class: Mammalia

Order: Carnivora

Family: Canidae

 The maned wolf or Chrysocyon brachyurus is a canid that is native to South America. At first glance the maned wolf’s appearance is that of a fox with legs comparable to a deer, earning the nickname “fox on stilts”. However, being neither of the two, it is the tallest of all wild canids (1). Canids are the family that consists of domestic dogs, wolves, foxes, jackals, coyotes, and other mammals that are dog-like.

Range and Habitat

Source: IUCN Red List

The maned wolf is found native to Central and South America. More specifically, the species is found to live in central and southeastern Brazil, Paraguay, eastern Bolivia, and northern Argentina. (2) According to a study carried out in 2005, Brazil was found to contain the largest population of maned wolves at an approximation of 21,745. (3) Despite the belief that the maned wolf became extinct in Uruguay in the nineteenth century, the species is now thought to be present in small numbers in Uruguay again. (4) Whether the species truly survived or the animal redistributed to this location again is not absolute. The maned wolf inhabits these locations because of its need for the vast variety of grasslands and scrub forest. Research has shown that they tend to favor regions with low to medium shrub density. Therefore, maned wolves inhabit the variety of tall grasslands, shrub forests, woodland that still contains an open canopy, wet fields, and even land that is used for agriculture and pasture. (3) These types of environments generate prospective hunting grounds for the species. While resting during the day, the maned wolf can be found in: gallery forests which are located near a water source and also border more open land, a cerrado which is considered a tropical Savannah, or marshy areas near rivers. (3)

Physical Description
Being the only species of the genus Chrysocyon, the maned wolf is a unique animal from the canid family. It acquired its nickname the “fox on stilts” due to the fact that an average maned wolf stands almost a meter tall. The rare long legs of this species are thought to be an adaptation to help them see better in their habitat. (5) This would enable them to see prey or any type of approaching threat in the tall grass and shrubbery. Without this feature it would appear very similar to the red fox or Vulpes vulpes. The maned wolf’s coat is a golden red color and it has a long pointed muzzle. It has large erect ears that can also play a key role in hunting. The species receives its true name, the maned wolf, from the long black mane-like fur that is present on the back of the head down to the shoulders. When the animal senses danger, the black mane is known to stand erect. (4) The feet of the animal also are black like it is wearing black stockings while the throat, tail, and inside of the ears are white in color. (6) The average shoulder height of the maned wolf is about 74-78 centimeters while the total head-body length is about 1.2-1.3 meters long. They weigh an average of 20-23 kilograms. (4) The dentition of the maned wolf provides an idea to the type of diet they consume. They have reduced upper carnassials or shearing teeth, weak upper incisors, and long slender canines which display further evidence that they do not kill or consume large prey. (5)

Behavior 
The maned wolf is nocturnal and crepuscular meaning they are primarily active during the night and at dusk and dawn hours. (6) They most often rest during daylight hours in thicker brush where they are concealed. This animal is omnivorous and its diet consists of mainly fruit and small to medium size prey. Research of the diet has found that the primary food source is a fruit that is common to the range that comes from the lobeira plant, Solanum lycocarpum, which produces “wolf’s apples”. (3) The maned wolf may also prey on armadillos, rabbits, pampas deer, birds, reptiles, insects, fish, and arthropods. (4) They manipulate their large ears to listen for prey moving in the grass. In addition, the maned wolf is also known to tap the ground with one of their front feet to flush out prey so it can then pounce on it. (2) 

Even though this animal is related to the wolf it does not hunt in a pack. The maned wolf actually spends most of its life as a solitary individual. The maned wolf is factitively monogamous throughout its life and only comes together with its mate during breeding season. The mating season is between April and June after which the female gives birth to one to five pups. (7) Together the breeding pair covers a permanent home range of about 27 square kilometers. However, their only interaction is during the breeding season; otherwise, they remain independent from each other. They hunt, travel, and rest in solitude. (5) The territories of each pair are established by urine and feces deposits and respected by other mated pairs. 

There have been some behavioral differences observed in captivity compared to the wild. Although as expected of the species, opposite sex pairs cooperate better than same sex pairs in the captive environments. Specifically, mated pairs display different social behaviors in captivity. In these situations, they have been observed to groom each other, eat together, and rest together. The males have also been observed contributing to parental care including: grooming, food portioning, and defense. (5)

 Physiology 
The maned wolf prefers and displays the solitary lifestyle in the wild. In order to remain the independent breeding duo of a particular area of land, the maned wolf must be able to effectively mark its territory. It does this through chemical communication with its urine and feces deposits. The maned wolf exclusively sends out strong chemical signals known by a unique and strong odor produced by their excretions. The specific “message” is encoded by the particular volatile substances that vaporize from the urine surface. (9) Interestingly enough, the maned wolf’s “message” has been observed to smell very similar to marijuana. (8) This distinctive urine is not only necessary for identifying and communicating one’s territory, but also for finding one’s mate during the breeding season. A study was carried out to determine this chemical oddity discovered a presence of pyrazine-based compounds found unique to maned wolves in comparison with Mexican Gray Wolves, domestic dogs, and clouded leopards. The compound 2,5-dimethylpyrazine was found consistently in high concentrations in all of the maned wolf urine samples. (9) Pyrazines comprise a group of compounds that are notorious for very powerful odors often found in nature. They are commonly found among many insects and plants as pheromones or toxins. (9) This study confirms that the main possible function is to alert others not to enter their territory through the use of the strong odor and specific deposit patterns of excretion. An additional association may be linked with the concept of “reminding” others due to its extensive persistence. The pyrazine compounds establish an immediate warning as well as a continual reminder of the maned wolf territorial markings. Maned wolves have been observed to most often respect these lines of territory and this may explain why. This powerful chemical communication establishes the maned wolf’s home and environment to itself, its mate, and others. (9)

Conservation Status 
Currently and since 2004, the IUCN has classified the maned wolf as near threatened in regards to their conservation status. This status change was marked as significant improvement for the species because it was previously classified as vulnerable from 1982 to 1994. In 1996, the population experienced its first step towards improvement by becoming a lower risk and borderline near threatened. (3) They maintain the current status as a result of the continual issues that pose threats to the species. The main threat that the maned wolf suffers from is the expansion of human populations and their agricultural regions. The cultivation of the grasslands into agricultural land has created a drastic decline in the maned wolf’s natural habitat. (3) While they are still able hunt in the cultivated land, many farmers are not understanding of the unique animal and a great deal are hunted down and killed. (10) An additional threat to the species involves contracting disease, especially from domestic dogs. Domestic dogs can transfer diseases to the maned wolf, compete for their food, and even kill them. (4) Disease also occurs in captivity and many captive breeding attempts result in disease, usually parvovirus. (6) A large proportion of maned wolves are also killed by vehicles on highways. Road kills are considered to be the cause of death for about half of the yearly pup production in some maned wolf reserves. (4) 

Actions has been taken during the course of the decline of the maned wolf population. A Species Survival Plan (SSP) has been developed to promote captive breeding of the species. (10) Many zoos across the United States have been contributing to this plan and increasing the population. The Smithsonian Conservation Biology Institute is developing a process that would apply modern reproduction techniques to the breeding programs. Artificial insemination would drastically help the species where sexually and socially compatible pairs are necessary for mating and ultimately reproduction. Also, artificial insemination has the potential of creating more genetic diversity in a population that is based on pairs mating for life. (1) In addition, countries in South America have also taken action to help the species by legally protecting it in Brazil and creating hunting laws. (6) The maned wolf has also been labeled as endangered in Argentina to raise awareness of the drop. (3) Further information on human encroachment in these locations and the specific impacts to the different ranges will help produce more effective action for maned wolf conservation.

Resources

(1) Endangered Canids: The Maned Wolf - National Zoo| FONZ. (n.d.). Retrieved November 13, 2014, from http://nationalzoo.si.edu/SCBI/ReproductiveScience/Canids/ManedWolf.cfm 

(2) Maned Wolf Facts. (n.d.). Retrieved November 13, 2014, from http://nationalzoo.si.edu/Animals/Amazonia/Facts/manedwolffacts.cfm 

(3) Rodden, M., Rodrigues, F., & Bestlemeyer, S. (2008, January 1). Chrysocyon brachyurus. Retrieved November 13, 2014, from http://www.iucnredlist.org/details/full/4819/0 

(4) Maned wolf (Chrysocyon brachyurus). (n.d.). Retrieved November 14, 2014, from http://www.arkive.org/maned-wolf/chrysocyon-brachyurus/ 

(5) Gorog, A. (1999). Chrysocyon brachyurus: Maned Wolf. Retrieved November 14, 2014, from http://animaldiversity.ummz.umich.edu/accounts/Chrysocyon_brachyurus 

(6) Ginsberg, J., & Macdonald, D. (1990). Foxes, Wolves, Jackals, and Dogs: An Action Plan for the Conservation of Canids. Retrieved November 14, 2014, from https://portals.iucn.org/library/efiles/documents/1990-008.pdf 

(7) Fletchall, N., Rodden, M., & Taylor, S. (Eds.). (1995). Husbandry Manual for the Maned Wolf: Chrysocyon brachyurus. Retrieved November 15, 2014, from http://www.2ndchance.info/vaccination-ManedWolf1995.pdf 

(8) Switek, B. (2011). Maned Wolf Pee Demystified. Retrieved November 15, 2014, from http://phenomena.nationalgeographic.com/2011/03/10/maned-wolf-pee-demystified/ 

(9) Childs-Sanford, S. (2005). Identification of Volatile Compounds in the Urine and Feces of the Maned Wolf, Chrysocyon brachyurus. Retrieved from Drum Library, Maryland.

(10) Maned Wolf. (n.d.). Retrieved November 15, 2014, from http://www.endangeredwolfcenter.org/educational-resources/maned-wolf/#.