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Brazilian Guinea Pig

Cavia aperea

French: Cobaye du Brésil / German: Gemeines Meerschweinchen / Spanish: Cobaya comun

Taxonomy. Cavia aperea Erxleben, 1777,

“Brazil, Pernambuco.”

Seven subspecies are recognized.

Subspecies and Distribution.

C.a.apereaErxleben,1777 —EBrazil.

C.a.anolaimaeJ.A.Allen,1916 —highelevationsoftheEasternAndesrangeinColombiaandVenezuela,andtheCordilleradeMéridainNWVenezuela.

C.a.guianaeThomas,1901— NAmazonBasininColombia,Venezuela,theGuianas,andNBrazil.

C. a.hypoleucaCabrera,1953 —ParaguayandNArgentina.

C.a.nanahmas, 1917— EslopeoftheAndesandYungasmontaneforestsofC Bolivia;thereisareportedrecordforSEPeru,howeverthisNlimitofthedistributionisconsideredunresolved.

C.a.pamparumThomas,1901 —SBrazil,Uruguay,andEArgentina.

C. a. rosida Thomas, 1917 — the Serra do Mar in E Parana State, SE Brazil.

Descriptive notes. Head-body 215-395 mm, ear 19-23 mm, hindfoot 38-46 mm; weight 500-790 g. Greatest lengths of skull are 52-73 mm. Male Brazilian Guinea Pigs are heavier than females. The seven subspecies vary in external measurements, color, and morphology; nana is the smallest subspecies and the nominate aperea is the largest. General characteristics are olive-brown dorsum, flecked with brown and black, and paler venter that varies from whitish to yellowish gray. General body form is very reminiscent of the domestic Guinea pig (C. porcellus).

Habitat. Dry grasslands, upland savannas, moist savanna, cerrado woodland with shrub cover, and even gallery forests. Brazilian Guinea Pigs also occur in agricultural areas and along roadsides and railway right-of-ways. It does not burrow but constructs tunnels and runways in vegetation.

Food and Feeding. Brazilian Guinea Pigs are grazers and depend heavily on grasses. They also eat inflorescences and seeds.

Breeding. Brazilian Guinea Pigs breed year-round, and females can have five liters/ year under ideal conditions. Gestation is c.62 days, and litter sizes are 1-5 young (average 2-3). Newborns weigh ¢.60 g and are highly precocial. Females reach sexual maturity at c.2 months and males at ¢.3 months.

Activity patterns. Brazilian Guinea Pigs are diurnal, with peaks in morning and early evening. They are active year-round.

Movements, Home range and Social organization. Population ecology and social behavior of the Brazilian Guinea Pig have been widely studied. Home range size is highly variable, much like morphology. Home ranges of males vary from 165 m* to 1387 m* across studies; home ranges of females are significantly smaller but equally variable. Male home ranges overlap multiple female home ranges, but males maintain relatively exclusive home ranges among themselves. Density estimates range from 12-5 ind/ha in Brazil to 38 ind/ha in Argentina. Both sexes form strong linear dominance hierarchies, and males can control access to multiple females via male—male aggression. Males therefore exhibit female defense polygyny and form either a pair bond or control access to multiple females. Rate of multiple paternities is low.

Status and Conservation. Classified as Least Concern on The IUCN Red List. It is abundant throughout a very large distribution and tolerates a moderate amount of habitat modification.

Bibliography. Adrian & Sachser (2011), Canevari & Vaccaro (2007), Dunnum (2015), Dunnum & Salazar-Bravo (2010a), Eisenberg & Redford (1999), Redford & Eisenberg (1992), Rood (1970, 1972), Woods & Kilpatrick (2005).