Greater capybara
The capybara (Hydrochoerus hydrochaeris) is a giant cavy rodent native to South America. It is the largest living rodent and a member of the genus Hydrochoerus. Its close relatives include guinea pigs and Rock cavies, and it is more distantly related to the agouti, the chinchilla, and the nutria.
The capybara has a heavy, barrel-shaped body and short head, with reddish-brown fur on the upper part of its body that turns yellowish-brown underneath. Its sweat glands can be found on the surface of the hairy portions of its skin, an unusual trait among rodents. The animal lacks down hair, and its guard hair differs little from over hair. Capybaras have slightly webbed feet and vestigial tails. Their hind legs are slightly longer than their forelegs; they have three toes on their rear feet and four toes on their front feet. Their muzzles are blunt, with nostrils, and the eyes and ears are near the top of their heads.
The range of capybara covers a huge area, extending over much of South America to the east of the Andes, from Colombia and Venezuela southwards to northern Argentina. Capybara is found in lowland areas with close proximity to water. Preferred habitats include rainforest lakes and rivers, marshes, brackish wetlands, swamps as well as seasonally flooded grasslands and savannas.
Capybaras are social animals, forming family units of 10 - 30 animals, although group size often depends on the environment. Thus, during the dry season, when the animals gather at dwindling pools, temporary concentrations of up to 100 individuals can be observed. A typical family group of capybaras consists of one dominant male, one or more subordinate males, one or more related females as well as offspring of different ages. Meanwhile, males tend to be more solitary. Adult individuals of the group participate in defending their territory against outsiders, scent-marking their range with secretions from their scent glands. Being crepuscular, capybaras spend the daytime hours resting, and being active in the morning and evening. Where capybaras face persecution by humans, they usually tend to be nocturnal. When threatened, these animals are known to flee, either running over land or diving into the water.
Capybaras are herbivores (graminivores). As grazers, these rodents primarily consume grasses and aquatic plants, complementing their diet with bark and fruits. Being coprophagous, they are re-ingest the previous day’s food.
These animals have polygynous to polygynandrous (promiscuous) mating systems, where individuals of both sexes can mate with multiple mates. Dominant males often limit access to other males to females. Both males and females can choose mates. Mating occurs in water. If a female doesn't want to mate with the male, she can dive or come out of the water. Capybaras breed throughout the year with a peak period, occurring from May to June, which coincides with the early rainy season. The gestation period lasts for 150 days, yielding a litter of 2-8 babies. Offspring of this species are born precocial. After a short while, the babies are able to stand and walk. Within the first week of their life, they begin grazing. The mother and other related females of the group suckle the young until weaning, which occurs at 3 months old. After that, the young remain in the group of their parents until 1 year old, becoming mature by 12-18 months old.
One of the biggest threats to the overall population of this species is hunting. The animals are hunted for their meat and hide. They also attract hunters for grease, found in their thick and fatty skin, which has pharmaceutical value. Capybaras are considered to be a pest species and are killed by farmers, who believe these animals destroy cereal or fruit crops as well as compete with domestic livestock, which isn't true.
According to IUCN, the Capybara is locally common and widespread throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) on the IUCN Red List.
In certain parts of their range, these animals are the only large grazers, hugely controlling the vegetation of the area. On the other hand, capybaras are a source of food for jaguars, green anacondas, spectacled caimans, and other predators of their habitat.