Pacas: Agoutidae

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PACAS: Agoutidae

PHYSICAL CHARACTERISTICS

There are two species of paca: Agouti paca, commonly known as the paca, and Agouti taczanowskii, commonly known as the mountain paca. Though the genus name Agouti may be confusing, pacas and agoutis (family Dasyproctidae) are not in the same family. Pacas are among the largest of all rodents, with a head and body length of 20 to 30.5 inches (50 to 77.4 centimeters) and weight of 13.2 to 31 pounds (6 to 14 kilograms.) Their tail length is 5 to 9 inches (13 to 23 centimeters).

The paca resembles the mountain paca in most features, except the paca is slightly larger, has thinner and harsher fur, shorter nostrils, larger eyes, and thicker claws.

In both species, the upper body fur varies from reddish brown to dark chocolate or smoke-gray. There is a pattern of white or pale yellow irregular spots on the sides, arranged in rows of two to seven. The average number of rows is four. One or two upper rows are shorter and limited to the rear half of the body. Two or more middle rows run from the neck to the rump.

GEOGRAPHIC RANGE

Pacas are found from southern Mexico to northern Argentina. Their range includes Belize, Bolivia, Brazil, Colombia, Costa Rica, Cuba, Ecuador, El Salvador, French Guiana, Guatemala, Guyana, Honduras, Nicaragua, Panama, Paraguay, Peru, Suriname, and Venezuela.

HABITAT

Pacas primarily live in tropical rainforests but are also found in a wide variety of forest habitats, including mangrove swamps, deciduous and semi-deciduous forest, dense upland scrub, and narrow growth along river banks.

DIET

Both species of paca eat mainly fruit but their diet changes throughout its range and based on the seasons. Other foods include roots, seeds, leaves, buds, and flowers. In the wild, pacas are herbivores, meaning they eat only plants. In captivity, they are omnivores, meaning they eat both plants and flesh. Pacas in zoos eat fruits, vegetables, raw meat, lizards, and insects.

BEHAVIOR AND REPRODUCTION

Pacas are nocturnal, meaning that they are most active at night, and solitary animals. In the wild, they have sometimes been seen active in the early morning and late afternoon. During the day, they sleep in a den dug under tree roots or rock outcroppings, or in hollows in trees, usually along riverbanks or hillsides. The den usually has several entrances or exits concealed by leaves.

Pacas are capable swimmers and when they feel threatened, take to the water where they can remain submerged for up to fifteen minutes. They have an acute sense of smell and hearing. They walk along fixed trails, but should a trail become disturbed by humans or other animals, they will abandon it.

Pacas breed year-round. Females are sexually mature, able to mate, at nine months, while males are sexually mature at one year. The gestation, or pregnancy, period is 114 to 119 days. Females have one or two litters of young a year, each usually with one baby but in rare instances, two babies.

NAME CHANGE

In the 1700s, the scientific name for the paca was Cuniculus brisson and in the twentieth century it was called Odobenus brisson. In the early twentieth century, it was known by the common name of coelogenys. The paca is called conejo pintado in Panama, tepezcuintle in Costa Rica, guardatinajas in Mexico, hee in Suriname, and lapa in Venezuela. Paca is the common name in Brazil and Argentina.

PACAS AND PEOPLE

Pacas are hunted by humans for their meat and are often killed by farmers who see them as agricultural pests. However, pacas are important dispersers of seeds from the Attalea oleifera palm tree in the Brazilian Atlantic Forest, and Virola surina-mensis, a commercial timber tree.

CONSERVATION STATUS

Pacas and mountain pacas are not listed as threatened by the IUCN. However, several wildlife surveys show their numbers in the wild are dwindling, due to extensive hunting and habitat destruction by humans.

PACA (Agouti paca): SPECIES ACCOUNT

Physical characteristics: The paca has a head and body length of 20 to 20.5 inches (50 to 77.4 centimeters) and a weight of 13 to 31 pounds (6 to 14 kilograms). They have course, slick, glossy fur that is gray, red, black, or brown on the upper body and white on the lower body. They may also have four horizontal rows of cream, gray, or white spots or marks on their sides. Pacas have four toes on their front paws and five on their back feet. They also have a somewhat arched back.

Geographic range: Pacas live in east-central Mexico to Paraguay, including Belize, Brazil, Colombia, Costa Rica, El Salvador, French Guiana, Guatemala, Guyana, Honduras, Nicaragua, Panama, Suriname, and Venezuela.

Habitat: Pacas live primarily in rainforests near rivers and streams. They can also be found in seasonally dry areas, swamps, and deciduous forests bordering water sources.

Diet: Pacas are herbivores that feed on leaves, stems, roots, seeds, and fruit, especially avocados and mangos. Pacas do not climb trees so they depend on tree-climbing animals such as monkeys, to drop fruit from trees.

Behavior and reproduction: Pacas are nocturnal, meaning they are most active at night. During the day, they sleep in a den dug under tree roots or rock outcroppings, usually along riverbanks or hillsides. The den usually has several entrances and exits concealed by leaves. Pacas are capable swimmers and take to the water when they feel threatened. They have an acute sense of smell and hearing.

The paca is monogamous and territorial, with a mated pair sharing a territory, which can be up to 8.6 acres (3.5 hectares). However, their territories are not exclusive and may overlap with other pairs of pacas.

Female pacas usually have one litter of babies a year but can have two or three. A litter contains one or two babies. Their gestation period, the time they carry their young in the womb, is 114 to 119 days.

Pacas and people: Pacas are hunted by humans for their meat. They are often killed by farmers who see them as pests.

Conservation status: Pacas are not listed as threatened by the IUCN. ∎

FOR MORE INFORMATION

Books:

Domestication and Husbandry of the Paca (Agouti paca) (FAO Conservation Guide: 26). United Nations, NY: Food and Agriculture Organization of the United Nations (FAO), 1995.

Eisenberg, J. F., and K. H. Redford. Mammals of the Neotropics. Vol. 3, The Central Tropics: Ecuador, Peru, Bolivia, Brazil. Chicago: University of Chicago Press, 1999.

Macdonald, David. The New Encyclopedia of Mammals. Oxford, U.K.: Oxford University Press, 2001.

Nowak, Ronald M. Walker's Mammals of the World, 6th ed. Baltimore: Johns Hopkins University Press, 1999.

Periodicals:

Laska, M., et al. "Food Preferences and Nutrient Composition in Captive Pacas, Agouti paca (Rodentia, Dasyproctidae)." Mammalian Biology (January 2003): 31–41.

Pérez, Elizabeth M. "Agouti paca." Mammalian Species (December 1992): 1–7.

Pimentel, Domingos S., and Marcelo Tabarelli. "Seed Dispersal of the Palm Attalea oleifera in a Remnant of the Brazilian Atlantic Forest." Biotropica (March 2004): 74–84.

Ramirez–Pulido, Jose, et al. "New Records of Agouti paca (Linnaeus) from the Mexican State of Puebla." The Texas Journal of Science (August 2001): 285.