The Patagonian mara (otherwise known as Patagonian cavy or hare) is a large rodent with a rather strange appearance. At first glance, this animal looks like a small deer with long ears, similar to these of a hare. Each of this animal's front limbs has 4 sharp claws, which are used in digging. Meanwhile, the hind legs are strong and longer, allowing the rodent to quickly flee and escape from predators.
The Patagonian maras are diurnal animals. The legs of these rodents are designed for running. They spend the greater part of the year travelling in male-female pairs and rarely form groups of more than 3 individuals. The daytime hours of these pairs are spent in daily foraging trips. They usually prefer grazing grounds that are rich with vegetation. These animals are also known to gather in settlements - large groups, living in warrens or den systems. Usually small warrens are used by a single pair, whereas big ones may be used by up to 29 pairs simultaneously. As a result, population density of this species sharply increases and groups of up to 70 individuals are formed. During active period of the day, Patagonian maras can often be seen sunbathing. When resting, they base themselves upon their haunches or fold their forelegs under their body like cats.
These rodents have a well-defined monogamous mating system, where individuals form pairs, remaining together throughout their lives. Meanwhile, males are the ones who maintain the pair-bond: they constantly guard their mates, following females wherever they go. Breeding occurs between August and January. Gestation period lasts for 90 days, yielding 2 young per litter. Babies are born near the burrow entrance. Newborn maras are well-developed and their eyes are open. Immediately after birth, the babies are able to move into the burrow that is often shared with several other pairs and their young. The babies live in this burrow, visited and suckled by their mother every day. Nursing period lasts for 75 - 78 days, after which young maras usually disperse, although some of them may remain with their parents until the following breeding season. The age of sexual maturity is 6 months old for males and 2.5 months old for females.
The overall population of this species is currently facing a serious decline due to hunting, loss of their natural habitat as well as competition with the European hares, sheep and other non-native herbivores. Some local population in Buenos Aires Province have gone extinct because of continuous hunting for their skin and habitat clearance, as a result of agricultural development.
The IUCN Red List and other sources don’t provide the number of the Patagonian maras’ total population. Numbers of this species are decreasing today, and the Patagonian mara is currently classified as Near Threatened (NT) on the IUCN Red List.
As grazing herbivores, these rodents have a huge impact of the local ecosystem. They act as seed dispersers of certain plants they consume. In addition, young of this species are key prey items for a number of predators, including birds, canids and felids.