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Chacoan peccary
At the Phoenix Zoo
Conservation status
Endangered (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Artiodactyla
Family:	Tayassuidae
Genus:	Catagonus
Species:	C. wagneri
Binomial name
Catagonus wagneri (Rusconi, 1930)
Synonyms
Parachoerus wagneri Rusconi, 1930

The Chacoan peccary or Tagua (Catagonus wagneri) is a species of peccary found in the Gran Chaco of Paraguay, Bolivia and Argentina. About 3000 exist in the world. It is believed to be the closest living relative to the extinct genus Platygonus.

The Chacoan Peccary has the unusual distinction of having been first described in 1930 based on fossils and was originally thought to be an extinct species. In 1971 the animal was discovered to still be alive in the Chaco region, in the Argentine province of Salta. The species was well known to the native people, but it took a while for scientists to rediscover its existence. It is known locally as the Tagua.

  Geographic range

The Chacoan Peccary is endemic to the Gran Chaco in Paraguay, Bolivia and northern Argentina.^[1]

  Habitat

Chacoan peccaries have received the nickname "pigs from green hell" because of their wild, impenetrable habitats.^{[citation needed]} The Chacoan peccary is confined to hot, dry areas. Dominated by low-lying succulents and thorny bushes, the Gran Chaco is approximately 140,000 square kilometers. There are a few scattered giant trees, but the majority of the vegetation is thorny scrub vegetation. The Chacoan peccary has developed adaptations like well-developed sinuses to combat dry, dusty conditions. The feet are also small, which allows maneuverability among spiny plants.

  Physical characteristics

The largest of the three generally accepted species of peccaries, the Chacoan peccary has many pig-like features. The Chacoan peccary is an ungulate possessing a well-formed rostrum with a tough, leathery snout. The bristle-like fur is generally brown to almost gray. A dark stripe runs across the back, and white fur is found on the shoulders. The Chacoan peccary differs from its fellow peccary species by having longer ears, snout, and tail. It has white hairs around the mouth, unlike other peccaries. Catagonus wagneri also possesses a third hind toe, while other peccaries only have two. The hypsodont teeth follow this dental formula: 2/3, 1/1, 3/3, 3/3 . The upper canines also display the distinguishing trait of peccaries, pointing downwards instead of out and up like other Suiformes. When the Chacoan peccary is nervous or frightened it flees, while raising the hairs on its back. While escaping, the Chacoan peccary sprays secretions from their dorsal glands. This is thought to be a signal for other peccaries to keep the group together through the dense bush.^[2]

  Reproduction

Young are generally born between the months of September and December, but litters have been found almost year-round. Births have been linked to periods of food abundance and rainfall. The average number of embryos has been recorded as approximately 2.72. Females may leave the herd to give birth and then return afterwards. Newborns are precocial, able to run a few hours after birth. The pelage of the young resembles that of the adults. There is no sexual dimorphism.

  Behavior

Chacoan peccaries often travel in herds of up to twenty individuals. They are active during the day, especially in the morning when they are most apt to travel. Herds display a general travel cycle within the homerange of 42 days. This allows the individuals to monitor and show ownership over their areas.

These social mammals communicate by various sounds ranging from grunts to chatters of the teeth. Even though individuals may occasionally exhibit aggressive behavior like charging and biting, this species is not as aggressive as others.

As a defensive strategy, members of a herd may line up in a defensive wall; this makes the herds easy targets for hunters. The Chacoan peccary produces a milky, odorous substance that is used for marking trees, shrubs and similar. The substance is secreted from glands located on the back, and is dispersed by rubbing. Frequently bathing in mud or dust, Chacoan peccaries also defecate at particular "stations".

  Chacoan peccary at St Louis Zoo

  Food habits

The arid habitat of the Gran Chaco region provides very tough vegetation for the Chacoan peccary. These peccaries feed on various species of cacti, species like Cleistocactus baumannii and Opuntia discolor. The Chacoan peccary uses its tough snout to roll the cacti on the ground, rubbing the spines off. It may pull off the spines with its teeth and spit them out. The kidneys are specialized to break down acids from the cacti. The two-chambered stomachs are also well suited to digest tough foods like cacti. Occasionally grazing on bromeliad roots, it also eats acacia pods and fallen cacti flowers. This species of peccary seeks out salt licks formed from ant mounds and construction projects like road building and land clearings. The Chacoan peccary gains essential minerals like calcium, magnesium, and chlorine from the salt licks.

  Conservation status

Because the Chacoan peccary is endemic to a formerly isolated region of South America, it is most vulnerable to human activity. Just as quickly as this species is discovered in an area, it disappears. Herd numbers are decreasing as a result of habitat loss and fragmentation. The range of the Chacoan peccary is being quickly transformed into large Texas-style ranches. Hunting also continues as well as an unidentified disease that has plagued the herds in recent years. Efforts are underway to breed Chacoan peccaries in captivity, but the species does not survive well outside of the wild. Preserves have also been established in Paraguay, but are not highly enforced.

  References

Wikispecies has information related to: Catagonus

Wikimedia Commons has media related to: Catagonus wagneri

• Mayer, J. J.; Wetzel, R. M. (1986). "Catagonus wagneri". Mammalian Species 259: 1–5. 
• Wetzel, R. M. (1977a). "The extinction of peccaries and a new case of survival". Annals of the New York Academy of Science 288: 538–544. DOI:10.1111/j.1749-6632.1977.tb33641.x. 
• Wetzel, R. M. (1977b). "The Chacoan peccary, Catagonus wagneri (Rusconi)". Bulletin of the Carnegie Museum of Natural History 3: 1–36. 
• Wetzel, R. M.; Dubos, R. E.; Martin, R. L.; Myers, P. (1975). "Catagonus, an 'extinct' peccary alive in Paraguay". Science 189 (4200): 379–381. DOI:10.1126/science.189.4200.379. PMID 17840828.