Order: Rodentia – Rats, mice, gopher, chinchilla, beaver, porcupine
Family: Caviidae – cavies, guinea pigs
Scientific Name: Dolichotis patagonum
Description: The Patagonian cavy is a large, long-legged rodent that resembles a small deer. The upperparts are gray to brown, and the underparts are white. They have a white patch on the neck and white fur on the rump, similar to the rump patches of many deer and antelope. Their head is large, with a long muzzle and large eyes and ears. The tail is very short. Their hind feet have 3 digits each, and each digit has a large hoof-like claw. The forefeet have 4 digits, each with a sharp claw for digging. Cavies reach 2 ½ feet in length and weigh up to 35 pounds.
Home Range: Natural range is Argentina in South America; a population has been introduced into Brittany, France
Habitat Type: Pampas and arid areas with coarse grass or scattered shrubs
Reproduction: Patagonian cavies form life-long pair bonds. Most pairs breed communally, gathering at a “settlement” to give birth and rear their young. A settlement is a system of burrows within a clearing, and can be used by as many as 29 pairs. In Argentina, most pairs produce only one litter each year, occasionally two. Gestation is approximately 3 months. There are 1-3 young per litter, (usually 2) and most litters are born in August-November (spring in the southern hemisphere). Females give birth outside of a burrow entrance. The young are born completely furred, with their eyes and ears open. They can walk within minutes of birth, and they enter the burrow on their own. The mother visits the burrow at least once each day to allow her young to suckle. Her mammae are located on her sides, so that she can sit upright and stay alert for predators while her young are suckling. Mothers try to nurse only their own young, but they cannot always fend off the others – in this way, orphaned young may still be able to survive in the communal dens. The young begin to eat solid food within a few days, but they remain in the den for up to 4 months, emerging only to suckle or graze. Young are weaned at about 11 weeks. Females can reproduce when they are 8 months old.
Diet in the Wild: Grass, low shrubs, and any other vegetation available
Diet in the Zoo: Grass that grows naturally in their yard, ADF 16 pellets, and fruits and vegetables
General Information: Patagonian cavies occupy a similar ecological niche to our North American jackrabbit. They are terrestrial and diurnal. They may find shelter in vegetation or in burrows of other animals, but in their open habitat their speed is their most important defense. They can gallop quickly: one was clocked running beside a car at 27 miles per hour for more than a ½ mile. They are capable of bursts of speed up to 35 miles per hour. When they are excited (but not yet alarmed enough to run) they use a form of locomotion called stotting, bouncing on all four legs at once. They walk when undisturbed, or hop like a rabbit. When they are not moving, they sometimes sit with their front feet tucked under them, similar to a small cat. They use their forepaws to wipe their face.
Although the basic social unit is the mated pair, they join together in colonies (called troops) of up to 70 individuals. Males establish a dominance hierarchy in the troop by intimidating or fighting with other males. Each male defends his mate and the area around her from other males. In captivity cavies are usually silent, but a number of different calls and whistles have been recorded from wild colonies.
Conservation Status: This species is declining in the wild due to habitat destruction and competition with the European hare, which has been introduced into Argentina and can reproduce more quickly than the cavy. Listed on IUCN Red List as Near Threatened.
Predators: Foxes, wild cats, and birds of prey. They are also hunted by farmers, who consider them to be pests.
Animal: The Definitive Visual Guide to the World’s Wildlife. 2001. D. Burnie and D.E. Wilson. Dorling Kindersly, London and New York. p.158.
Encyclopedia of Mammals. 1998. E. Gould and G. McKay. Academic Press, San Diego. p. 226.
“Argentina’s Running Rodent” ZooNooz, San Diego Zoo newsletter. December 1997. K.W. Fink.
Walker’s Mammals of the World, Ed. 6, Vol. 2. 1999. R.M. Nowak. Johns Hopkins University Press, Baltimore. pp. 1670-1672.