Capybara

Capybara[1]
Conservation status
Least Concern (IUCN 3.1)[2]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Subphylum:	Vertebrata
Class:	Mammalia
Order:	Rodentia
Suborder:	Hystricomorpha
Family:	Caviidae
Subfamily:	Hydrochoerinae
Genus:	Hydrochoerus
Species:	H. hydrochaeris
Binomial name
Hydrochoerus hydrochaeris (Linnaeus, 1766)
Range of H. hydrochaeris (green)

The capybara (Hydrochoerus hydrochaeris ^[1][3][4]), also known as capivara in Portuguese,^[5] and capibara, chigüire in Venezuela, Colombia, and Ecuador ronsoco in Peru, chigüiro, and carpincho in Spanish,^[6][5][7] is the largest living rodent in the world.^[8] Its closest relatives are agouti, chinchillas, coyphillas, and guinea pigs.^[9] Its common name, derived from Kapiÿva in the Guarani language,^[5] means "master of the grasses"^[10] while its scientific name, both hydrochoerus and hydrochaeris, comes from Greek ὕδρω (hydro = water) + χοίρος (choiros = pig, hog).

Description

Capybaras have heavy, barrel-shaped bodies and short heads with reddish-brown fur on the upper part of their body that turns yellowish-brown underneath. Adult capybaras grow to 107 to 134 cm (3.51 to 4.40 ft) in length, stand 50 to 64 cm (20 to 25 in) tall at the withers and typically weigh 35 to 66 kg (77 to 150 lb), with an average in the Venezuelan llanos of 48.9 kg (108 lb).^[11][12][13] The top recorded weight are 105.4 kg (232 lbs) for what was likely a zoo-kept specimen^{[original research?]}, 91 kg (200 lb) for a wild female from Brazil and 73.5 kg (162 lb) for a wild male from Uruguay.^[14][15] Capybaras have slightly webbed feet, no tail and 20 teeth.^[16] Their back legs are slightly longer than their front legs and their muzzles are blunt with eyes, nostrils, and ears on top of their head. Females are slightly heavier than males.

Its karyotype has 2n = 66 and FN = 102.^[1]

Fossil record and other species

Life restoration of the extinct Protohydrochoerus

A larger capybara called Neochoerus pinckneyi once existed in North America, having invaded that continent during the Great American Interchange that followed formation of the Isthmus of Panama. Other fossil caviomorphs that were eight times the size of modern capybaras have been called "capybaras" by the popular press, but were actually dinomyids related to the pacarana.^[16]

There is also an extant "lesser capybara", Hydrochoerus isthmius, with a disjoint range in Colombia, Venezuela and Panama.^[3]

Ecology

A group of capybaras at Hato La Fe in the Los Llanos region of Venezuela

Capybara are semi-aquatic mammals^[13] found wild in much of South America (including Colombia, Ecuador, Bolivia, Venezuela, Brazil, Argentina, Guyana, Suriname, French Guiana, Uruguay, Peru, and Paraguay^[10]) in densely forested areas near bodies of water, such as lakes, rivers, swamps, ponds and marshes,^[11] as well as flooded savannah and along rivers in tropical forest. They roam in home ranges of 25–50 acres (10–20 ha).^[16]

Many escapees from captivity can also be found in similar watery habitats around the world. Sightings are fairly common in Florida, although a breeding population has not yet been confirmed.^[17] Though it has been erroneously stated that a population of capybara existed in the River Arno in Florence, Italy, this was determined to be the nutria or coypu (Myocastor coypus), a considerably smaller South American aquatic rodent with a similar appearance. Recently, it has been spotted in the Central Coast of California.^[18]

Diet and predation

Capybaras are herbivores, grazing mainly on grasses and aquatic plants,^[6][11] as well as fruit and tree bark.^[13] An adult capybara will eat 6 to 8 pounds (2.7 to 3.6 kg) of grasses per day.^[16] Capybara are very selective feeders with four to six plant species making 75% of its diet.^[19] They will select the leaves of one species and disregard other species surrounding it.^[20] Capybaras eat a greater variety of plants during the dry season as there are fewer plants available. While they eat grass during the wet season, they have to switch to reeds during the dry season as they are more abundant.^[20] Plants that capybaras eat during the summer lose their nutritional value in the winter and are thus not consumed at that time.^[19] The capybara's jaw hinge is non-perpendicular and they thus chew food by grinding back and forth rather than side-to-side.^[8] Capybaras are coprophagous, meaning they eat their own feces as a source of bacterial gut flora and to help digest the cellulose in the grass that forms their normal diet and extract the maximum protein from their food. They may also regurgitate food to masticate again, similar to cud-chewing by a cow.^[21]

Like its cousin the guinea pig, the capybara does not have the capacity to synthesize vitamin C, and capybaras unsupplemented with vitamin C in captivity have been reported to develop gum disease as a sign of scurvy.^[22]

Diorama of a green anaconda devouring a capybara

They can have a life span of 8–10 years in the wild^[23] but average a life less than four years as they are "a favourite food of jaguar, puma, ocelot, eagle and caiman".^[10] The capybara is also the preferred prey of the anaconda.^[24] Capybara are farmed for meat and skins in South America.^[25] It is widely believed that capybara were declared by Papal Bull to be fish so they may be eaten during Lent.^[26] Because of this belief, poaching increases during the period right before Easter.^[25]

Natural history

Capybaras are very gregarious. While they do sometimes live solitarily they are more commonly found in groups that average 10-20 individuals, with 2-4 of them being adult males, 4-7 being adult females and the rest being juveniles.^[27] Capybara groups can consist of as many as 50 or 100 individuals during the dry season,^[21][28] when the animals gather around available water sources. Males are organized in stable, linear hierarchies. The dominant male in each group is significantly heavier than any of the subordinates, but among subordinates, status is not correlated with weight.^[29] The dominant male is positioned in the center of the group while subordinates are on the periphery. These hierarchies are established early in life among the young with play fights and mock copulations.^[27] The most dominant males have access to the best resources.^[29] Capybaras are very vocal and, when in groups, chatter with each other to establish social bonds, dominance or general group census.^[28] They can make a dog-like bark which is made when the animals are threatened or when females are herding young.^[30] The bark of a capybara is often mistaken for that of a dog.^[21]

Capybara have two different scent glands; a morillo, located on the snout, and an anal gland. Both sexes have those glands but males have larger morillos and their anal pockets can open more easily. The anal glands of males are also lined with detachable hairs. A crystalline form of scent secretion is coated on these hairs and are release when in contact with objects like plants. These hairs have a longer lasting scent mark and are tasted by other capybaras.^[31] A capybaras marks by rubbing its morillo on an object or by walking over a scrub and marking with its anal gland. A cabypara can spread its scent further by urinating.^[31] However females usually mark without urinating and mark less frequently than males overall. Females mark more often during the wet season when they are in estrus. In addition to objects, males will also mark females.^[31]

Mother with typical litter of four babies

Reproduction

When in estrus, the female's scent changes subtly and nearby males begin pursuit.^[29] In addition, a female will alert males that she is in estrus by whistling though her nose.^[21] During mating, the female has the advantage and mating choice. Capybaras mate only in the water and if a female does not want to mate with a certain male she will either submerge or leave the water.^[21][28] Dominant males are highly protective of the females, however they usually can’t prevent all the subordinates from copulating.^[29] The larger the group, the harder it is for the male to watch all the females. Dominant males secure significantly more matings than each subordinate, but subordinate males, as a class, are responsible for more matings than each dominant male.^[29] The lifespan of the capybara's sperm is longer than that of other rodents.^[32]

Capybara gestation is 130–150 days and usually produces a litter of four capybara babies, but may produce between two and eight in a single litter.^[12] Birth is on land and the female will rejoin the group within a few hours of delivering the newborn capybaras, who will join the group as soon as they are mobile. Within a week the young can eat grass, but will continue to suckle - from any female in the group - until weaned at about 16 weeks. Youngsters will form a group within the main group.^[10] Alloparenting has been observed in this species.^[28] The rainy season of April and May mark the peak breeding season.^[5] Like other rodents, the front teeth of capybaras grow continually to compensate for the constant wearing-down from eating grasses;^[10] their cheek teeth also grow continuously.^[8] When fully grown, a capybara will have coarse hair that is sparsely spread over their skin, making the capybara prone to sunburn. To prevent this, they may roll in mud to protect their skin from the sun.^[16]

Activities

Capybara lounging in a shallow pool in captivity

A capybara yawns at Ueno Zoo.

Capybaras are excellent swimmers and can survive, completely underwater for up to five minutes,^[11] an ability they will use to evade predators.^{[citation needed]} If necessary, a capybara can sleep underwater, keeping its nose just over the waterline.

During midday, as temperatures increase, they wallow in water and then graze in late afternoons and early evenings when it is cooler. They sleep little, usually dozing off and on throughout the day and grazing into and through the night.

Conservation and human interaction

Capybara are not on the IUCN list^[9] and therefore not considered a threatened species; their population is stable through most of their South American ranges, though in some areas hunting has reduced their numbers.^[10][11]

Capybaras are hunted for their meat and pelts in some areas,^[7] and otherwise killed by humans who see their grazing as competition for livestock. In some areas they are farmed, which has the effect of ensuring that the wetland habitats are protected. Their survival is aided by their ability to breed rapidly.^[10]

6 week old pet capybara being bottle fed

Capybaras can be found in many areas in zoos and parks,^[8] and may live for 12 years in captivity.^[10] Capybaras are gentle and will usually allow humans to pet and hand-feed them.

The meat is said to taste like pork.^[5] During Lent, capybara meat is especially popular in parts of South America, especially in Venezuela, as it is claimed that the Catholic Church, in a special dispensation, allowed capybara meat to be consumed on days that consumption of meat was otherwise not allowed. There are differing accounts of how the dispensation arose.^[5][16][33] Capybaras are occasionally kept as pets in the United States,^[34] though it is illegal in some states and in various other countries.

See also

• Beaver

References

1. ^ ^{a b c} Woods, Charles A.; Kilpatrick, C. William (16 November 2005). "Infraorder Hystricognathi (pp. 1538-1600)". In Wilson, Don E., and Reeder, DeeAnn M., eds. Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore: Johns Hopkins University Press, 2 vols. (2142 pp.). p. 1556. ISBN 978-0-8018-8221-0. OCLC 62265494. http://www.bucknell.edu/msw3/browse.asp?id=13400218. 
2. ^ "Hydrochoerus hydrochaeris". IUCN Red List of Threatened Species. Version 2011.1. International Union for Conservation of Nature. 2008. http://www.iucnredlist.org/apps/redlist/details/10300. Retrieved 17 June 2011. 
3. ^ ^{a b} Hydrochoerus hydrochaeris (capybara). University of Michigan Museum of Zoology, Animal Diversity Web. Retrieved on December 16, 2007.
4. ^ Darwin, Charles R. (1839), Narrative of the surveying voyages of His Majesty's Ships Adventure and Beagle between the years 1826 and 1836, describing their examination of the southern shores of South America, and the Beagle's circumnavigation of the globe. Journal and remarks. 1832-1836., London: Henry Colburn, p. 619 
   • In page 57, Darwin says "The largest gnawing animal in the world, the Hydrochærus Capybara (the water-hog), is here also common."
   • See it also in The Complete Work of Charles Darwin Online
5. ^ ^{a b c d e f} Capybara Natural History. JunglePhotos.com. Retrieved on December 16, 2007.
6. ^ ^{a b} (Spanish) J Forero-Montana, J Betancur, J Cavelier. "Dieta del capibara Hydrochaeris hydrochaeris (cavia: Hydrochaeridae) en Caño Limón, Arauca, Colombia", Rev. biol. trop, Jun. 2003, vol.51, no.2, pp. 571–578. ISSN 0034-7744. PDF available (English translation)
7. ^ ^{a b} "Trip to South America gives new meaning to outdoors life" from inRich.com (Link last retrieved/verified 17 January 2008)
8. ^ ^{a b c d} Capybara. San Francisco Zoo. Retrieved on December 17, 2007.
9. ^ ^{a b} Capybara (Hydrochoerus hydrochaeris). Chester Zoo (UK). Retrieved on December 17, 2007
10. ^ ^{a b c d e f g h} Capybara. Bristol Zoo Gardens (UK). Retrieved on December 16, 2007.
11. ^ ^{a b c d e} Capybara Facts. Smithsonian National Zoological Park. Retrieved on December 16, 2007.
12. ^ ^{a b} The Encyclopædia Britannica (1910) Capybara (from Google Books)
13. ^ ^{a b c} Capybara. Palm Beach Zoo. Retrieved on December 17, 2007.
14. ^ http://www.waza.org/virtualzoo/factsheet.php?id=110-020-001-001&view=Rodents%20and%20Hares&main=virtualzoo
15. ^ [1] (2011).
16. ^ ^{a b c d e f} Capybara fact sheet
17. ^ Florida Fish and Wildlife Conservation Commission: Capybara - Hydrochaeris hydrochaeris
18. ^ A gnawing question answered: It's a capybara roaming Paso Robles
19. ^ ^{a b} Quintana, R. D., S. Monge, et al. (1998). "Feeding patterns of capybara Hydrochaeris hypdrochaeris (Rodentia, Hydrochaeridae) and cattle in the non-insular area of the Lower Delta of the Parana River, Argentina." Mammalia 62(1): 37-52.
20. ^ ^{a b} Barreto, G. R. and E. Herrera (1998). "Foraging patterns of capybaras in a seasonally flooded savanna of venezuela." Journal of Tropical Ecology 14(1): 87-98.
21. ^ ^{a b c d e} Lord-Rexford, D. (1994). "A descriptive account of capybara behaviour." Studies on neotropical fauna and environment. 29(1): 11-22.
22. ^ PMID 10682750
23. ^ Burton M and Burton R. The International Wildlife Encyclopedia. Marshall Cavendish, 2002 , ISBN 076147269X, p. 384
24. ^ Capybara, the master of the grasses: pest or prey Sounds and Colours. Retrieved on January 23, 2011.
25. ^ ^{a b} San Diego Zoo, Capybara, Hydrochoerus hydrochaeris: October 2008, http://library.sandiegozoo.org/factsheets/capybara/capybara.htm, retrieved 22 June 2011 
26. ^ Von Humboldt, Alexander; Bonpland, Aimé (1854) [1852], "III" (in English), Personal Narrative of the Travels to the Equinoctial Regions of America, During the years 1799 - 1804., 2, London: Henry G. Bohn, p. 521, http://books.google.com/books?id=DM8XAAAAYAAJ 
27. ^ ^{a b} Alho, C. J. R. and N. L. Rondon (1987). "Habitats, population densities, and social structure of capybaras (hydrochaeris hypdrochaeris rodentia) in the pantanal Brazil." Revista Brasileira de Zoologia 4(2): 139-149.
28. ^ ^{a b c d} Macdonald, D. W. (1981). "Dwindling resources and the social behavior of Capybaras, (Hydrochoerus hydrochaeris) (Mammalia)." Journal of Zoology 194: 371-391.
29. ^ ^{a b c d e} Herrera, E. and D. W. Macdonald (1993). "Aggression, dominance, and mating success among capybara males (Hydrochaeris hypdrochaeris)." Behavioral Ecology 4(2): 114-119.
30. ^ Murphey, R. M., J. S. Mariano, et al. (1985). "Behavioral observations in a capybara colony (Hydrochaeris hypdrochaeris)." Applied Animal Behaviour Science 14: 89-98.
31. ^ ^{a b c} Macdonald, D. W., K. Krantz, et al. (1984). "Behavioral anatomical and chemical aspects of scent marking among capybaras Hydrochaeris-hypdrochaeris rodentia caviomorpha." Journal of Zoology 202(3): 341-360.
32. ^ Paula, T. A. R., H. Chiarini-Garcia, et al. (1999). "Seminiferous epithelium cycle and its duration in capybaras (Hydrochaeris hypdrochaeris)." Tissue & Cell 31(3): 327-334.
33. ^ Ellsworth, Brian. "In Days Before Easter, Venezuelans Tuck Into Rodent-Related Delicacy". New York Sun(March 24, 2005)
34. ^ http://www.ajc.com/lifestyle/rodents-of-unusual-size-289164.html