By Cody Krause
Geographic Range
Cuniculus taczanowskii is found in the higher elevation mountain ranges of Colombia, Ecuador, Peru, and Venezuela. (Eisenberg and Redford, 1992; Emmons, 1990; Lorentsen, 2005; Nowak, 1999)
Biogeographic Regions:
neotropical 
(native ).
Habitat
(6560 to 11480 ft)
Mountain pacas live at elevations of 2000 to 3500 meters with most individuals found between 2000 and 3050 meters. They are terrestrial but live near rivers or swampy areas in dense forest thickets. They often use water to escape when in danger as they are good swimmers. They are nocturnal and spend the daytime in underground burrows they construct which are up to 5 meters deep. (Donegan et al., 2004; Eisenberg and Redford, 1992; Emmons, 1990; IUCN, 2006; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996; The National Academies Press, 1991)
These animals are found in the following types of habitat:
temperate ; terrestrial .
Wetlands: swamp .
Other:
agricultural ; riparian .
Physical Description
(13.2 to 26.4 lbs)
(23.62 to 32.28 in; avg. 27.56 in)
Mountain pacas are large rodents, resembling large guinea pigs with an average weight of 9 kg and a length of 70 cm. Females are slightly smaller than males. They have short legs and rotund bodies with large heads and eyes. The skull is easily recognized, with an exceptionally large zygomatic arch. Pelage is red-brown to chocolate brown with two to seven white spots on the flanks; the young are born with this pelage as well. Mountain pacas have similar pelage to their close relative, Cuniculus paca, but with a denser undercoat to withstand the colder temperatures in the mountains. (Donegan et al., 2004; Eisenberg and Redford, 1992; Emmons, 1990; IUCN, 2006; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996; The National Academies Press, 1991)
Some key physical features:
endothermic ; homoiothermic; bilateral symmetry .
Sexual dimorphism: male larger.
Reproduction
Mountain pacas give birth up to two times each year.
Seasonality of mating is not known in mountain pacas.
Mountain pacas have a monogamous mating system, although males and females live alone. Mates live in separate dens which are normally in close proximity. Other mating behaviors are unknown. (Donegan et al., 2004; Eisenberg and Redford, 1992; Emmons, 1990; Lorentsen, 2005; Nowak, 1999)
Mating systems:
monogamous .
Mountain paca reproduction is not well studied, but is thought to be like that of Cuniculus paca (pacas) and much of the information below is based om that species. Pacas breed year round with a gestation period of around 118 days, and can give birth to two litters per year. A single offspring is usually produced with twins being rare. Young weigh 450 to 800g at birth, growing quickly to maturity at age of 1. Pacas are weaned at about 3 months old and females experience a post-partum estrous. (Donegan et al., 2004; Eisenberg and Redford, 1992; Emmons, 1990; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996)
Key reproductive features:
iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous ; post-partum estrous.
Like other mammals, female mountain pacas invest heavily in their offspring through gestation, lactation, and other care of the young. Male parental investment is not known in mountain pacas. (Donegan et al., 2004; Eisenberg and Redford, 1992; Emmons, 1990; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996)
Parental investment:
precocial ; pre-fertilization (provisioning, protecting: female); pre-hatching/birth (provisioning: female, protecting: female); pre-weaning/fledging (provisioning: female, protecting: female).
Lifespan/Longevity
There is little data on wild lifespan of mountain pacas and there are few in captivity. A lifespan of 12.5 years was recorded in the wild. (Donegan et al., 2004; Eisenberg and Redford, 1992; Emmons, 1990; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996)
Behavior
Mountain pacas are nocturnal and solitary animals. They live in burrows they construct in clay soils along river banks. Mountain pacas are found most frequently in dense forest, but are sometimes seen in open areas. Because of their size, they make a lot of noise when walking and are easily found by predators. (Donegan et al., 2004; Eisenberg and Redford, 1992; Emmons, 1990; IUCN, 2006; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996; The National Academies Press, 1991)
Home Range
Mountain pacas have small home ranges which usually overlap with the home range of their mate. Mated pairs in the closely related species Cuniculus paca will jointly defend their home ranges. (Donegan et al., 2004; Eisenberg and Redford, 1992; Emmons, 1990; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996)
Communication and Perception
Mountain pacas are not highly social animals and few vocalizations are known. They sometimes bark and grind their teeth. Like most mammals, they probably use chemical cues in communication. (Eisenberg and Redford, 1992; Emmons, 1990; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996)
Food Habits
Mountain pacas are opportunistic frugivores. They feed primarily on fruits and nuts, sometimes eating small grains. They often bring their food to a central midden in their large, fur-lined cheek pouches. Mountain pacas are important seed dispersal agents of many fruiting tree species. (Eisenberg and Redford, 1992; Emmons, 1990; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996)
Plant Foods:
leaves; seeds, grains, and nuts; fruit.
Foraging Behaviors:
stores or caches food .
Predation
- humans (Homo sapiens)
- jaguars (Panthera onca)
- large snakes (Serpentes)
Mountain pacas avoid predation by being nocturnal and cryptically colored. Their brown, spotted pelage allows them to blend in with the forest undergrowth. They are also good swimmers and usually escape to the water or their den when being chased by a predator. (Donegan et al., 2004; Eisenberg and Redford, 1992; Emmons, 1990; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996)
Anti-predator adaptations::
cryptic .
Ecosystem Roles
Mountain pacas are important seed dispersers in their forested habitats. They prey mainly on fruit and nuts and will carry them in their cheek pouches to other locations where they then eat or drop them, causing dispersal of the plant seed. (Donegan et al., 2004; Eisenberg and Redford, 1992; Emmons, 1990; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996)
Key ways these animals impact their ecosystem:
disperses seeds.
Economic Importance for Humans: Negative
Mountain pacas cause few problems for humans. They have been known to cause some crop damage to fruit and nut crops in some areas. (Donegan et al., 2004; Eisenberg and Redford, 1992; Emmons, 1990; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996; The National Academies Press, 1991)
Ways that these animals might be a problem for humans:
crop pest.
Economic Importance for Humans: Positive
Mountain pacas are hunted extensively for food. Hunts occur at night with spotlights and with dogs by day. The meat is veal-like and fetches high market prices. Paca farms have been suggested as a sustainable and economically viable business. (Donegan et al., 2004; Eisenberg and Redford, 1992; Emmons, 1990; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996)
Ways that people benefit from these animals:
food .
Conservation Status
IUCN Red List: [link]:
Lower Risk - Near Threatened.
US Federal List: [link]:
No special status.
CITES: [link]:
Appendix III.
State of Michigan List: [link]:
No special status.
Mountain pacas are listed as "low risk" by the IUCN. In some areas they are rare because of hunting pressures, in other areas populations are high, up to 90 per square km. Reserves protect mountain pacas from hunting in some areas. (Donegan et al., 2004; Eisenberg and Redford, 1992; Emmons, 1990; IUCN, 2006; Lorentsen, 2005; Nowak, 1999; Ojasti, 1996; The National Academies Press, 1991)
For More Information
Find Cuniculus taczanowskii information at
Contributors
Tanya Dewey (editor), Animal Diversity Web, University of Michigan Museum of Zoology.
Cody Krause (author), University of Wisconsin Stevens Point. Chris Yahnke (editor, instructor), University of Wisconsin Stevens Point.
