The Cuniculus paca, formerly known as Agouti paca is in the Order Rodentia under the Family Cuniculidae, which contains only one other species, the mountain paca (A. taczanowskii) (Wainwright 2007). The paca was formerly in the same family as the agouti in the Family Dasyproctidae.
Being the largest rodent in Costa Rica (Henderson 2002), the paca can be 70cm in length and weigh up to 9kg (28in., 20lbs.). The males are larger than females. The hind tracks are about 5cm wide and the skull length is about 19cm (Wainwright 2007). C. pacas are similar to the agouti and tapir, having a pig-like body shape with the upper reddish brown parts marked with horizontal rows of cream-colored spots along the sides. They are strictly nocturnal terrestrial mammals that live in burrows and hollow logs during the day (Smith 1983). As a defense mechanism against predators and to intimidate same-species rivals, the pacas can produce loud sounds of amplified grunts, growls, barks, and tooth-grinding noises. This is possible due to the unusually swollen zygomatic arch (the cheek bone) that acts as a resonating chamber, which is unique to mammals. Young pacas make a meowing sound until about a month old (Wainwright 2007).
Pacas are found in the neotropical regions of the Americas. They range from northeastern Mexico to Paraguay, Northern Argentina, and all the way down to southeastern Brazil. They likely do not inhabit any further north than the tropical subdeciduous forest of the Sierra Madre Oriental in northern Mexico. They have also been introduced in Algeria and Cuba. Paca are common and widely populated in the northern extent of their range, but are sparsely dispersed in the southern areas. There are 5 subspecies of pacas: the main subspecies present throughout this range is the Cuniculus paca paca.
Biogeographic Regions: nearctic (Native ); palearctic (Introduced ); neotropical (Native )
Pacas range from southeastern Mexico to northern Paraguay. They primarily live near streams in rainforest habitats. In Costa Rica, they are uncommon but found most on both the Pacific and Caribbean slopes from sea level up to 3,000m (10,000ft) (Wainwright 2007).
There are two species of pacas under the genus. There is the lowland or spotted paca and the mountain paca. Healthy adult lowland pacas, whether male or female, weigh in at about 6 to 12 kg, with males typically being slightly larger. Average adult length ranges from between 65 to 82 cm in males and 60 to 70 cm in females. They are a reddish-brown to darker brown color dorsally and have several rows of whitish spots down each side. Their underside is a lighter brown. Pacas are practically tailless, with short legs and a large, blunt head which make them slow and cumbersome on land, however they are quite good swimmers. They have four digits on their forefeet and 5 on their hindfeet. Cheek teeth are high-crowned (hypsodont), with a dental formula of incisors 1/1, canines 0/0, premolars 1/1, and molars 3/3 equaling 20, for a total of 40 teeth. They have a very broad zygomatic arch, which is coupled with concavities in the maxillary bones to form a reasonating chamber. The lowland paca is closely related to the mountain paca. Mountain pacas are typically smaller and have a thicker coat. There are also a number of differences in the morphology of the skull between the two species. Mountain pacas when compared with lowland pacas, have a less convex surface on the jugal bone. The infraorbital canal is also wider on the mountain pacas, and the suborbital process is more noticeable. Also, the nasal is more robust and longer, and the foramen is wider and deeper. Studies show that basal metabolic rates of lowland pacas average 0.44 with a standard deviation of 0.006 cubic cm of oxygen per g h (n=10, N=1) in subadult pacas averaging 4.5 kg, and about 0.30 with a standard deviation of 0.010 cubic cm of oxygen per g h (n=14, N=1) in adult pacas averaging 9 kg. This difference in metabolic rate is likely caused by higher activity levels while in captivity of the younger pacas. Body temperature typically remains around 37.0 with a standard deviation of 0.10°C (n=46, N=2) while at temperatures under 30°C. Pacas also have a high thermo conductance, reflective of their relatively thin coat. Subadults have a thermo conductance of around 0.037 with a standard deviation of 0.0005 cubic cm of oxygen per g h °C (n=24, N=1), while adults had a value of around 0.031±0.0012 cubic cm of oxygen per g h °C (n=8, N=1).
Range mass: 7 to 12 kg.
Range length: 60 to 82 cm.
Average basal metabolic rate: 0.30 ± 0.010 cm3.O2/g/hr.
Sexual Dimorphism: male larger
Other Physical Features: endothermic ; bilateral symmetry
Catalog Number: USNM 65952
Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Mammals
Sex/Stage: Male; Adult
Preparation: Skin; Skull
Collector(s): E. Nelson & E. Goldman
Year Collected: 1894
Locality: Catemaco, Veracruz, Mexico, North America
Elevation (m): 305
Belizean Coast Mangroves Habitat
This species is found in the Belizean coast mangroves ecoregion (part of the larger Mesoamerican Gulf-Caribbean mangroves ecoregion), extending along the Caribbean Coast from Guatemala, and encompassing the mangrove habitat along the shores of the Bahía de Annatique; this ecoregion continues along the Belizean coast up to the border with Mexico. The Belizean coast mangroves ecoregion includes the mainland coastal fringe, but is separate from the distinct ecoregion known as the Belizean reef mangroves which are separated from the mainland. This ecoregion includes the Monterrico Reserve in Guatemala, the estuarine reaches of the Monkey River and the Placencia Peninsula. The ecoregion includes the Burdon Canal Nature Reserve in Belize City, which reach contains mangrove forests and provides habitat for a gamut of avian species and threatened crocodiles.
Pygmy or scrub mangrove forests are found in certain reaches of the Belizean mangroves. In these associations individual plants seldom surpass a height of 150 centimetres, except in circumstances where the mangroves grow on depressions filled with mangrove peat. Many of the shrub-trees are over forty years old. In these pygmy mangrove areas, nutrients appear to be limiting factors, although high salinity and high calcareous substrates may be instrumental. Chief disturbance factors are due to hurricanes and lightning strikes, both capable of causing substantial mangrove treefall. In many cases a pronounced gap is formed by lightning strikes, but such forest gaps actually engender higher sapling regrowth, due to elevated sunlight levels and slightly diminished salinity in the gaps.
Chief mangrove tree species found in this ecoregion are White Mangrove (Laguncularia racemosa), Red Mangrove (Rhizophora mangle), Black Mangrove (Avicennia germinans); the Button Mangrove (Conocarpus erectus) is a related tree associate. Red mangrove tends to occupy the more seaward niches, while Black mangrove tends to occupy the more upland niches. Other plant associates occurring in this ecoregion are Dragonsblood Tree (Pterocarpus officinalis), Guiana-chestnut (Pachira aquatica) and Golden Leatherfern (Acrostichum aureum).
In addition to hydrological stabilisation leading to overall permanence of the shallow sea bottom, the Belizean coastal zone mangrove roots and seagrass blades provides abundant nutrients and shelter for a gamut of juvenile marine organisms. A notable marine mammal found in the shallow seas offshore is the threatened West Indian Manatee (Trichecus manatus), who subsists on the rich Turtle Grass (Thalassia hemprichii) stands found on the shallow sea floor.
Wood borers are generally more damaging to the mangroves than leaf herbivores. The most damaging leaf herbivores to the mangrove foliage are Lepidoptera larvae. Other prominent herbivores present in the ecoregion include the gasteropod Littorina angulifera and the Mangrove Tree Crab, Aratus pisonii.
Many avian species from further north winter in the Belizean coast mangroves, which boast availability of freshwater inflow during the dry season. Example bird species within or visiting this ecoregion include the Yucatan Parrot (Amazona xantholora), , Yucatan Jay (Cyanocorax yucatanicus), Black Catbird (Dumetella glabrirostris) and the Great Kiskadee (Pitangus sulfuratus)
Upland fauna of the ecoregion include paca (Agouti paca), coatimundi (Nasua narica), Baird’s Tapir (Tapirus bairdii), with Black Howler Monkey (Alouatta caraya) occurring in the riverine mangroves in the Sarstoon-Temash National Park. The Mantled Howler Monkey (Alouatta palliata) can be observed along the mangrove fringes of the Monkey River mouth and other portions of this mangrove ecoregion.
Other aquatic reptiian species within the ecoregion include Morelet's Crocodile (Crocodylus moreletti), Green Turtle (Chelonia mydas), Hawksbill Sea Turtle (Eretmochelys imbricata), Loggerhead Sea Turtle (Caretta caretta), and Kemp’s Ridley (Lepidochelys kempi).
Rio Negro-Rio San Sun Mangroves Habitat
This taxon occurs in the Rio Negro-Rio San Sun mangroves, which consists of a disjunctive coastal ecoregion in parts of Costa Rica, extending to the north slightly into Nicaragua and south marginally into Panama. Furthermore, this species is not necessarily restricted to this ecoregion. Mangroves are sparse in this ecoregion, and are chiefly found in estuarine lagoons and small patches at river mouths growing in association with certain freshwater palm species such as the Yolillo Palm (Raphia taedigera), which taxon has some saline soil tolerance, and is deemed a basic element of the mangrove forest here. These mangrove communities are also part of a mosaic of several habitats that include mixed rainforest, wooded swamps, coastal wetlands, estuarine lagoons, sand backshores and beaches, sea-grasses, and coral reefs.
The paucity of mangroves here is a result of the robust influx of freshwater to the coastline ocean zone of this ecoregion. Among the highest rates of rainfall in the world, this ecoregion receives over six metres (m) a year at the Nicaragua/ Costa Rica national border. Peak rainfall occurs in the warmest months, usually between May and September. A relatively dry season occurs from January to April, which months coincides with stronger tradewinds. Tides are semi-diurnal and have a range of less than one half metre.
Mangroves play an important role in trapping sediments from land that are detrimental to the development of both coral reefs and sea grasses that are associated with them. Mangrove species including Rhizopora mangle, Avicennia germinans, Laguncularia racemosa, Conocarpus erecta and R. harrisonii grow alone the salinity gradient in appropriate areas. Uncommon occurrences of Pelliciera rhizophorae and other plant species associated with mangroves include Leather ferns Acrostichum spp., which also invade cut-over mangrove stands and provide some protection against erosion. In this particular ecoregion, the mangroves are associated with the indicator species, freshwater palm, Raphia taedigera. Other mangrove associated species are Guiana-chestnut ( Pachira aquatica) and Dragonsblood Tree (Pterocarpus officinalis).
Reptiles include the Basilisk Lizard (Basiliscus basiliscus), Caiman (Caiman crocodilus), Green Sea Turtle (Chelonia mydas), Leatherback Turtle (Dermochelys coriacea) and Green Iguana (Iguana iguana). The beaches along the coast within this ecoregion near Tortuguero are some of the most important for nesting green turtles. The offshore seagrass beds, which are among the most extensive in the world, are a source of food and refuge for the endangered Green Sea Turtle (Chelonia mydas). Several species of frogs of the family Dendrobatidae are found in this mangrove ecoregion as well other anuran species and some endemic salamander taxa.
Mammal species found in this highly diverse ecoregion include: Lowland Paca (Agouti paca), primates such as Mantled Howler Monkey (Alouatta palliata), Geoffrey's Spider Monkey (Ateles geoffroyi), White-faced Capuchin (Cebus capucinus), Brown-throated Sloth (Bradypus variegatus), Silky Anteater (Cyclopes didactylus) and Nine-banded Armadillo (Dasypus novemcintus). Also found in this ecoregion are carnivores such as Ocelot (Leopardus pardalis), Central American Otter (Lutra annectens), Jaguar (Panthera onca), Northern Racooon (Procyoon lotor), and Crab-eating Racoon (P. cancrivorus).
Moist Pacific Coast Mangroves Habitat
This taxon occurs in the Moist Pacific Coast mangroves, an ecoregion along the Pacific coast of Costa Rica with a considerable number of embayments that provide shelter from wind and waves, thus favouring mangrove establishment. Tidal fluctuations also directly influence the mangrove ecosystem health in this zone. The Moist Pacific Coast mangroves ecoregion has a mean tidal amplitude of three and one half metres,
Many of the streams and rivers, which help create this mangrove ecoregion, flow down from the Talamanca Mountain Range. Because of the resulting high mountain sediment loading, coral reefs are sparse along the Pacific coastal zone of Central America, and thus reef zones are chiefly found offshore near islands. In this region, coral reefs are associated with the mangroves at the Isla del Caño Biological Reserve, seventeen kilometres from the mainland coast near the Térraba-Sierpe Mangrove Reserve. The Térraba-Sierpe, found at the mouths of the Térraba and Sierpe Rivers, is considered a wetland of international importance.
Because of high moisture availability, the salinity gradient is more moderate than in the more northern ecoregion such as the Southern dry Pacific Coast ecoregion. Resulting mangrove vegetation is mixed with that of marshland species such as Dragonsblood Tree (Pterocarpus officinalis), Campnosperma panamensis, Guinea Bactris (Bactris guineensis), and is adjacent to Yolillo Palm (Raphia taedigera) swamp forest, which provides shelter for White-tailed Deer (Odocoileus virginianus) and Mantled Howler Monkeys (Alouatta palliata). Mangrove tree and shrub taxa include Red Mangrove (Rhizophora mangle), Mangle Caballero (R. harrisonii) R. racemosa (up to 45 metres in canopy height), Black Mangrove (Avicennia germinans) and Mangle Salado (A. bicolor), a mangrove tree restricted to the Pacific coastline of Mesoamerica.
Two endemic birds listed by IUCN as threatened in conservation status are found in the mangroves of this ecoregion, one being the Mangrove Hummingbird (Amazilia boucardi EN), whose favourite flower is the Tea Mangrove (Pelliciera rhizophorae), the sole mangrove plant pollinated by a vertebrate. Another endemic avain species to the ecoregion is the Yellow-billed Cotinga (Carpodectes antoniae EN). Other birds clearly associated with the mangrove habitat include Roseate Spoonbill (Ajaia ajaja), Gray-necked Wood Rail (Aramides cajanea), Rufous-necked Wood Rail (A. axillaris), Mangrove Black-hawk (Buteogallus anthracinus subtilis),Striated Heron (Butorides striata), Muscovy Duck (Cairina moschata), Boat-billed Heron (Cochlearius cochlearius), American White Ibis (Eudocimus albus), Amazon Kingfisher (Chloroceryle amazona), Mangrove Cuckoo (Coccyzus minor), Yellow Warbler (Setophaga petechia), and Black-necked Stilt (Himantopus mexicanus VU) among other avian taxa.
Mammals although not as numerous as birds, include species such as the Lowland Paca (Agouti paca), Mantled Howler Monkey (Alouatta palliata), White-throated Capuchin (Cebus capucinus), Silky Anteater (Cyclopes didactylus), Central American Otter (Lontra longicaudis annectens), White-tailed Deer (Odocoileus virginianus), feeds on leaves within A. bicolor and L. racemosa forests. Two raccoons: Northern Raccoon (Procyon lotor) and Crab-eating Raccoon (P. cancrivorus) can be found, both on the ground and in the canopy consuming crabs and mollusks. The Mexican Collared Anteater (Tamandua mexicana) is also found in the Moist Pacific Coast mangroves.
There are a number of amphibians in the ecoregion, including the anuran taxa: Almirante Robber Frog (Craugastor talamancae); Chiriqui Glass Frog (Cochranella pulverata); Forrer's Grass Frog (Lithobates forreri), who is found along the Pacific versant, and is at the southern limit of its range in this ecoregion. Example salamanders found in the ecoregion are the Colombian Worm Salamander (Oedipina parvipes) and the Gamboa Worm Salamander (Oedipina complex), a lowland organism that is found in the northern end of its range in the ecoregion. Reptiles including the Common Basilisk Lizard (Basiliscus basiliscus), Boa Constrictor (Boa constrictor), American Crocodile (Crocodilus acutus), Spectacled Caiman (Caiman crocodilus), Black Spiny-tailed Iguana (Ctenosaura similis) and Common Green Iguana (Iguana iguana) thrive in this mangrove ecoregion.
Pacas like a variety of habitats, typically being found in tropical evergreen and tropical subdeciduous forests. They have also apparently been found in pine-oak, cloud forests, and mangroves. Different studies have found a wide range of population density estimates, ranging all the way from over 90 individuals per sq km to as low as 6 individuals per sq km in areas with hunting pressures. These rodents can be found around disturbed habitats, and often construct burrows around riparian zones near water, however these sites can be prone to flooding. In patchy habitat areas, pacas use undisturbed zones of forest as dispersal corridors. Agricultural plantations of fruit-bearing crops often produce a simulated agroforest environment, which is often adjacent to natural forest. Pacas and other forest-dwelling species will use this corridor to disperse across their range. Their population density and range is typically determined by the presence of fruit-bearing trees, and the abundance of fruit on the forest floor. Other factors influencing their population density include abundance of predators, type of forest, presence of water, and availability of denning locations.
Range elevation: Sea Level to 2,300 m.
Average elevation: Below 1,600 m.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: forest ; rainforest
Habitat and Ecology
Cuniculus paca's habitat ranges from the riparian forest in Guanacaste, Costa Rica to moist and wet forests in the Caribbean and southern Pacific regions. Pacas can survive in forest fragments, farmland, and edges of cities where there are thickets to provide for adequate hiding places (Henderson 2002). They nest in dens in or around forests, usually near streams or other fresh water because they take refuge in water when their den is attacked by an aggressor (Wainwright 2007). Although they are common in relatively undisturbed forests, local densities of pacas vary year to year due to local variation in annual seed crop production from forest trees (Smith 1983).
Often along steep banks, Pacas nest in dens that a re roughly 3-9 m(10-30ft), 20cm wide (8in) and are made from digging or modifying other animal dens. Known to Costa Rican hunters as uzu, the burrows have one main entrance and one or more secret exits that are stuffed with leaves to conceal and used as an escape route when necessary (Wainwright 2007).
Pacas are frugivores, feeding mainly on fallen fruits, but will eat a wide variety of plant material including seeds, leaves, and tubers. Typically these rodents forage close to their denning grounds, and tend to limit their activity to a couple of small centers. Home range and activity will shift with fruit availability, often changing feeding locations around late August. Pacas will feed on native or foreign species of fruit. They prefer high energy foods such as mangos or avocados. They may eat the whole fruit, or may discard certain pieces of it. Pacas have been known to eat the seeds in addition to the fleshy part of the fruit. In a study done on captive pacas, spotted pacas were shown to have fruit preferences choosing with high energy contents, with mango (Mangifera indica), papaya (Carica papaya), and avocado (Persea americana) being some of the preferred foods. Introduced species such as jack-fruit (Artocarpus integrifolia) and buri (Polyandrococus caudensis) are also eaten. Some examples of vegetation the paca will not eat include flowering plants (Ocotea sps. and Terminalia sp), and palm trees (Irartea deltoidea). In the season between November and March, when there is a general shortage of fruit on the forest floor, pacas will browse on leaves and live off their fat reserves.
Plant Foods: leaves; roots and tubers; seeds, grains, and nuts; fruit
Primary Diet: herbivore (Folivore , Frugivore , Granivore )
Pacas forage fallen fruits and seeds at night and carry them to sheltered feeding spots. They may disperse a few seeds but not as much as the agouti (Janzen 1983). Favorite foods include cedro macho seeds, guavas, avocados, and mangoes. When food is scarce pacas rely on seedlings, leaves, and roots. To cope with their partly herbivorous diet, Cuniculus pacas are larger and longer large intestines than agoutis because foliage is a relatively low-energy food source and is slow and space-consuming to digest. They are also coprophagous, which means they eat their fecal pellets to extract important nutrients that was not available during the food's first passage (Wainwright 2007). Pacas may also visit gardens to eat corn, watermelons, or squash (Henderson 2002).
Predators of the Cuniculus paca include humans and mammals. The Speothos venaticus (nocturnal bush dog) is an adapted predator of the paca but they are able to escape by jumping into bodies of water and staying immersed for a considerable time (Smith 1983). They are able to jump high distances off the ground because their tibia is almost as long as the femur (Wainwright 2007). Pacas can also effectively escape in the extreme dark by leaping away from the predator then “freezing”, staying absolutely motionless for up to 45 minutes. The major predator of the paca are humans because they are the number one preferred game animal due to their easy capture, “excellent meat, and freedom from odor” (Janzen 1983).
Pacas and other herbivores (frugivores) have important influences on plant communities. Distribution and species richness of many plants are influenced by the actions of these mammals, meaning community composition and diversity are also affected. For some fruiting plant species (e.g. Attalea oleifera and Hymenaea courbaril) pacas are crucial in the regeneration of the species. The loss of pacas may result in loss of these tree species. Pacas are seed predators, they will eat the pods of many tree species (e.g. Hymenaea courbaril), and will effectively disperse the seeds throughout the forest. This action is important in the development of old-growth neotropical forests. Pacas could also be considered ecosystem engineers, because they dig burrows that other species use.
Pacas serve as an intermediate host for parasites (Echinoccus vogeli). This parasite develops in the liver of pacas, and can also develop in humans. In pacas, these parasites are only harmful if the parasite causes infections and any harm in people is a result of parasite-host incompatibility. Men who regularly ingest paca meat can succumb to human leptospirosis, a result of the presence of disease causing microorganisms (Leptospira interrogans). Leptospirosis can result in rashes, fevers, muscle pain, and in some cases afflictions of the liver and kidney. Pacas also commonly serves as a host for a variety of flea species (e.g. Rhipsideigma lugubris).
Ecosystem Impact: disperses seeds; creates habitat
- parasites (Echinoccus vogeli)
- leptospirosis (Leptospira interrogans)
- fleas (Rhipsideigma lugubris)
Hunting pressure is estimated in certain areas to result in roughly 150 animals being harvested per year in a 500 sq km area. (0.4 pacas per sq km). Hunting by farmers has increased even more so due to their tendency to damage crops. Pacas use their ability to swim as an escape method from predators. Pacas are preyed on by a number of predators such as the jaguar and the cougar. Bush dogs are also predators of paca, and it is believed the presence of paca is influences the geographic distribution of these canids.
- humans (Homo sapien)
- jaguars (Panthera onca)
- cougars (Puma concolor)
- bush dogs (Spethos venaticus)
Anti-predator Adaptations: cryptic
Life History and Behavior
Lowland pacas, like most mammals, perceive their environment mainly through auditory and olfactory. However, they also have very advanced visual systems, due to their nocturnal lifestyle. These rodents have retinal ganglion cells and a tapetum lucidum that enhances their vision at night, allowing them to see well in darkness. This gives them an advantage over other similar diurnal species during times of low lunar illumination. Pacas have modified zygomatic arches and maxillary bones to produce a call unique to this species. The maxillaries have concavities that are coupled with the modified cheek structure to form a resonating chamber. When air is pushed through the chamber, a low rumbling sound is produced.
Communication Channels: visual ; acoustic
Other Communication Modes: mimicry
Perception Channels: visual ; tactile ; acoustic ; chemical
The maximum lifespan for pacas in the wild is thought to be about 12.5 years, and the survival rate is estimated to be 80 percent. During the months between November and March there is often a shortage of food for the pacas. This time period is thought to be the limiting factor affecting population sizes of pacas. More often than not, the cause of death is being consumed by a predator, but pacas may be in a weakened state due to lack of food availability.
Status: wild: 12.5 (high) years.
Status: captivity: 12.5 (high) years.
Lifespan, longevity, and ageing
Cuniculus pacas in the wild can live up to 13 years and in captivity at least 16 years (Wainwright 2007).
Lowland pacas are monogamous, with a pair of adult pacas mating for life, and usually inhabiting a home range of around 3 hectares. Males need to establish dominance over the females. The male establishes dominance and reinforces the pair bond by urinating on the female (enurination), who may become very aggressive if she is not receptive to this behavior. They may form a loose family group consisting of the male, female, and their offspring.
Mating System: monogamous
Pacas typically only have one or two offspring per year, and breed year round uniformly. It is believed this is largely due to the availability of fruit year round. There have been a number of studies conducted on the reproduction specifics of pacas, and the data are very similar. Generally, the estrous cycle of females averages around 32.5 days. Gestation length is typically somewhere around 148.6 days in captivity, while in the wild it is shorter, at around 97 to 118 days. Time between birth events averages about 224.5 days in captivity, and between 172 and 191 in the wild. In captivity 55.5% of females studied had two birthing events per year with one young per event. Of these births 44.7% were female and 55.3% were male. Newborn females weighed in around 605.9 g, while males averaged about 736.7 g, with an average length of around 23 cm. Females and males typically reach sexual maturity between 8 and 12 months, with most animals being sexually mature by a year. Structure of paca populations are estimated at around 74% adults, 3% subadults 19% juveniles, 4% infants. Males and females are thought to exist in an equal ratio.
Breeding interval: Pacas breed once or twice per year.
Breeding season: Pacas breed year round uniformly.
Range number of offspring: 1 to 2.
Range gestation period: 97 to 118 days.
Average weaning age: 3 months.
Range time to independence: 2 to 6 months.
Range age at sexual or reproductive maturity (female): 8 to 12 months.
Range age at sexual or reproductive maturity (male): 8 to 12 months.
Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous
Female pacas care for young for as little as 8 weeks, all the way up to over 6 months with lactation occurring for approximately 3 months. This lactation period can also overlap with a new female pregnancies. They are highly precocial at birth, as young are born fully developed, with open eyes and the ability to run and eat solid food within a day. Young follow their mothers and learn or “imprint” on her behaviors. Newborn pacas grow quite rapidly, reaching 4 kg by about three months and 6 kg in six months.
Parental Investment: precocial ; female parental care ; pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Provisioning: Female, Protecting: Female)
Although C. pacas sleep and forage apart from their mate, they are monogamous and live over roughly 3ha (7.5 acres). Courtship involves a twisting, hopping dance during which the male tries to spray the female with urine. The female firsts avoids urine spray and may even attack the male but once sprayed with the males urine a few times, she allows him to approach. Pacas breed at any time of the year and usually produce one offspring with a gestation period of three and a half months. The females become sexually active at 9 months while the males after about a year.
Molecular Biology and Genetics
Statistics of barcoding coverage: Cuniculus paca
Public Records: 0
Specimens with Barcodes: 34
Species With Barcodes: 1
Lowland pacas are listed as a species of Least Concern according to the IUCN redlist, although there have been pockets of extirpation in the southern areas of its range due to habitat loss. The spotted paca is not a conservation concern, due to its wide distribution and large population. Some surveys suggest that there have been disturbing signs of population decline due to extensive hunting and habitat loss. However, other studies have shown that pacas are widespread in many protected areas and apart from small pockets no signs of population decline have been seen. The mixing of agricultural systems, along with primary and secondary forest has created good habitat for pacas to survive and thrive in present day neotropics. Threats to the species include loss of habitat, forest fragmentation, hunting, and introduction of domestic species.
IUCN Red List of Threatened Species: least concern
IUCN Red List Assessment
Red List Category
Red List Criteria
- 1996Lower Risk/least concern(Baillie and Groombridge 1996)
Isaac (2007) and the IUCN Red List of threatened species has the paca listed as Least Concern (LC).
Cuniculus pacas are rare or extinct over much of Costa Rica due to hunting and habitat loss. It is estimated that hunters kill almost 900 pacas each year in a 146 km squared area (56 square miles). Several small paca farms are present in Costa Rica but a few are fronts for illegal paca hunters. Paca farming could potentially be profitable and environmentally friendly (Wainwright 2007).
This rodent occurs at population densities of 84 to 93 individuals per square kilometer in suitable habitat in Colombia (Eisenberg and Redford 1999).
Relevance to Humans and Ecosystems
Pacas are considered to be a pest on crops, gardens, and plantations. When asked about mammalian species doing damage to agricultural operations, most farmers and workers mentioned the paca as a problem, rating it second after the cacao rat. Crops affected by the paca include cocoa and fruit bearing crops (e.g. jack-fruit and buri).
Negative Impacts: crop pest
Pacas are an important game animal throughout their range and are used for food quite consistently by people living in these areas. Firearms, traps, and dogs are all used to hunt pacas. Paca meat is highly sought after throughout its native range, and is considered to be an important food source. Roughly 70% of the average 10 kg paca consists of usable meat.
Positive Impacts: food
The Lowland Paca (Cuniculus paca), also known as the Spotted Paca, is a large rodent found in tropical and sub-tropical America, from East-Central Mexico to Northern Argentina. It is called paca in most of its range, but tepezcuintle in most of Mexico and Central America, jaleb in the Yucatan peninsula, conejo pintado in Panamá, guanta in Ecuador, majás or picuro in Peru, jochi pintado in Bolivia, and boruga in Colombia. It is also known as the gibnut in Belize, where it is prized as a game animal, labba in Guyana, lapa in Venezuela, and lappe on the island of Trinidad.
There is much confusion in the nomenclature of this and related species; see agouti. In particular, the popular term agouti or common agouti normally refers to species of the distinct Dasyprocta genus (such as the Central American Agouti, Dasyprocta punctata). Sometimes the word agouti is also used for a polyphyletic grouping uniting the families Cuniculidae and Dasyproctidae, which, besides the pacas and common agoutis, includes also the acouchis (Myoprocta). Cuniculus is the appropriate genus name instead of Agouti based on a 1998 ruling of the International Code of Zoological Nomenclature as the Lowland Paca's genus.
The Lowland Paca has coarse fur without underfur, dark brown to black on the upper body and white or yellowish on the underbelly. It usually has three to five rows of white spots along its sides, against a dark grey background. It has thick strong legs, with four digits in the forefeet and five in the hind feet (the first and fifth are reduced); the nails function as hooves. The tail is short and hairless. The zygomatic arch is expanded laterally and dorsally and is used as a resonating chamber - a unique feature among mammals.
An adult Lowland Paca weighs between 6 and 12 kg (13 and 26 lb). It has two litters per year, each having usually one young, sometimes two; gestation lasts 115–120 days. Pacas are sexually mature at about 1 year.
The Lowland Paca is mostly nocturnal and solitary and does not vocalize very much. It lives in forested habitats near water, preferably smaller rivers, and dig simple burrows about 2 m (6 ft 7 in) below the surface, usually with more than one exit. The Lowland Paca is a good swimmer and usually heads for the water to escape danger. It also is an incredible climber and it searches for fruit in the trees. Its diet includes leaves, stems, roots, seeds, and fruit, especially avocados, mangos and zapotes. It sometimes stores food.
Economical and ecological aspects
The Lowland Paca is considered an agricultural pest for yam, cassava, sugar cane, corn and other food crops. Its meat has excellent flavor and is highly prized. It is plentiful in protected habitats, and hence not in danger of extinction, but overall its numbers have been much reduced because of hunting and habitat destruction. It is easily bred and raised in farms, although the taste is said to be inferior (perhaps unpleasant) when farmed.
- ^ 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.). pp. 1538-1600. ISBN 978-0-8018-8221-0. OCLC 62265494. http://www.bucknell.edu/msw3/browse.asp?id=13400270.
- ^ Queirolo, D., Vieira, E., Emmons, L. & Samudio, R. (2008). Cuniculus paca. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on 5 January 2009.
- ^ http://books.google.com/books?id=9r9E_HBDAF0C&pg=PA7&lpg=PA7&dq=paca+boruga&source=bl&ots=iJKf7_ZRwz&sig=85N_UMlVKN-zmNktvXgJiSEuq_o&hl=en&ei=LhGlTOGcOo6ssAOQ6tn-Dg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBIQ6AEwAA#v=onepage&q=paca%20boruga&f=false
- ^ 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.). ISBN 978-0-8018-8221-0. OCLC 62265494. http://www.bucknell.edu/msw3/browse.asp?id=13400269.