Chacoan Mara

Dolichotis salinicola was formerly included in the genus Pediolagus as Pediolagus salinicola. A number of common names have been used to refer to this species, including Chacoan mara, dwarf mara, dwarf Patagonian cavy, dwarf Patagonian hare, and salt-desert cavy. In Spanish, it is called conejo del palo, which roughly translates to shrub rabbit.

Communication through scent is very important for this species. In captivity, Chacoan maras have been observed to saturate a site with their urine and anal gland secretions. Those sites then become their preferred locations for sandbathing as they provide all members of the group with the same scent. Individuals also urinate on one another as an additional way to share their scent. In addition to scent markings, Chacoan maras make a variety of vocalizations, many of which are very similar to those made by Patagonian maras. For example, young produce a “wheet” call when following and a “whine” when threatening conspecifics. When approached by conspecific rival, Chacoan maras may emit a prolonged wheet that generally drops to a low intensity grunt.

Communication Channels: acoustic ; chemical

Other Communication Modes: pheromones ; scent marks

Perception Channels: visual ; tactile ; acoustic ; chemical

According to the IUCN Red List of Threatened Species, Dolichotis salinicola is a species of least concern with no known major threats. This status is based on the species’ wide distribution, presumed large population, and because it is unlikely to be declining at a fast rate. Dolichotis salinicola is found in protected areas within Argentina, Bolivia and Paraguay.

US Federal List: no special status

CITES: no special status

IUCN Red List of Threatened Species: least concern

There are no known adverse effects of Chacoan maras on humans.

Chacoan maras are popular game animals throughout their geographic range. Indigenous hunters exploit them for food and for their pelts. The pelts of Patagonian maras, a close relative to Chacoan maras, have been made into bedspreads and rugs and sold in stores specializing in regional goods.

Positive Impacts: food ; body parts are source of valuable material

As common herbivores in the eastern Salta province, Chacoan maras are sometimes found in high densities and may have a significant impact on the local environment. Potential impacts may include overgrazing and the destruction of seedlings, which together prevent the forest regeneration. As herbivores, however, they may also be important seed dispersers. Chacoan maras are an important prey species for a number of medium to large bodied predators. Although limited information is available on parasites specific to Chacoan maras, they are known to host the tick species Amblyomma pseudoparvum.

Commensal/Parasitic Species:

• hard ticks (Amblyomma pseudoparvum)

Chacoan maras primarily forage on leaves and forbs, but also consume woody plants, grasses, fruits, seeds, and succulent species such as cacti and bromeliads. They most often forage on forbs and grasses during the rainy season, with cacti and bromeliads making up a majority of their diet during the dry season.

Plant Foods: leaves; seeds, grains, and nuts; fruit; flowers

Primary Diet: herbivore (Folivore )

Dolichotis salinicola ranges from the Chaco of Paraguay and the southernmost portion of Bolivia, south into northwestern Argentina and its Cordoba Province.

Biogeographic Regions: neotropical (Native )

Chacoan maras are endemic to the Chaco, a large area in Paraguay consisting of arid forests, thorny scrublands, wetlands, and seasonal rivers and streams. They are primarily found in low, flat, thorn scrub habitat, but also may be found in dry forests. They are often found at elevations ranging from 400 to 800 m throughout the Chaco.

Range elevation: 400 to 800 m.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: savanna or grassland ; scrub forest

Little information is available regarding the lifespan or longevity of Chacoan maras.

These rodents are relatively large compared to other caviids and resemble rabbits due to their long, thin legs, moderately large, broad, pointed ears, and long, stout vibrissae. They weigh 1.8 to 2.3 kg and range from 420 to 485 mm in head-body length, with their tail adding an additional 19 to 30 mm. They also have large hind feet that measure 91 to 30 mm, and they have nails rather than claws at the end of each digit. The ears range from 58 to 64 mm in length.

The pelage of Chacoan maras is short and smooth, with brownish gray to darker gray fur on their backs that is lightly speckled. Their sides are typically lighter in color, ranging from dark gray to white, and the neck and abdomen are also white. White patches can also be found on their foreheads and behind their eyes. Juveniles differ slightly in color than adults, in that they may have reddish-yellow coloration mixed in with the gray on their backs. Additionally, juveniles lack a third color on their flanks, as found on the adults.

Range mass: 1.8 to 2.3 kg.

Range length: 420 to 485 mm.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Major predators of Dolichotis salinicola include jaguars, pumas, and Pampas foxes. The coloration of their pelage helps camouflage them from predators and they often try evade predators by outrunning them. Young are born under the protection of dense vegetation and can run a high speeds a few hours after birth.

Known Predators:

• jaguars (Panthera onca)
• pumas (Felis concolor)
• Pampas foxes (Lycalopex gymnocerus)

Anti-predator Adaptations: cryptic

Little is known about the mating behavior of this species. Apart from activities related to reproduction, female and male Chacoan maras have little to no contact with one another. Even during estrus, females have been observed resisting or withdrawing from males.

Little information is available on the reproductive cycle of this species. Gestation lasts 2 months (77 days in captivity) and females bear 2 to 5 young per litter, with an average of 1.5 young per litter. Pups weigh approximately 199 g at birth.

Parturition is thought to occur in secluded areas throughout their range, such as under a thorn bush. Newborn Chacoan maras are precocial and can run a few hours after birth. Pups begin following adults a few days after parturition. In order to quickly acquire their natal groups scent, pups often roll around at the group’s urination site shortly after birth. Weaning begins around four weeks old.

Range number of offspring: 2 to 5.

Average number of offspring: 1.5.

Range gestation period: 2 (low) months.

Range weaning age: 4 weeks (low) minutes.

Key Reproductive Features: iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous

Little physical contact has been observed between adult and juvenile Chacoan maras. For example, females nurse their young in a sitting posture for bouts lasting an average of five minutes. Nursing occurs in open, exposed areas. Males generally do not participate in parental care, however, they do seem to tolerate young, which is evidenced through their resting and occasionally playing with juveniles. Scanet marking and play help integrate juveniles into the social unit.

Parental Investment: precocial ; female parental care ; pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female)

The Chacoan mara occurs in the Chaco of Paraguay, northwest Argentina as far south as Cordoba Province and the southernmost portion of Bolivia. It occurs at elevations @ 400-800 m above sea level in Bolivia. It occurs in the arid Chaco and is typically found in dry, low, flat thorn scrub, but also may be found in grasslands and dry thorny forests. It probably lives in primary and secondary habitat. It is a relatively large caviid and resembles a rabbit due to its long, thin legs, moderately large, broad, pointed ears and long, stout vibrissae. It weighs 1.8-2.3 kg and ranges from 420-485 mm in head-body length with their tail adding 19-30 mm. The large hind feet measure 91-130 mm and have nails rather than claws at the end of each digit. The ears range from 58-64 mm long. The pelage is short and smooth, with brownish gray to darker gray, lightly speckled fur on the back. The sides are typically lighter in color, ranging from dark gray to white, and the neck and abdomen are white. There are white patches on the foreheads and behind their eyes. Juveniles may have reddish-yellow coloration mixed in with the gray on the backs. They lack a third colour on their flanks, as found on adults. It lives in groups of up to four. It digs large burrows to sleep in at night. The burrows have extensive piles of dirt outside the entrances. The coloration of its pelage helps camouflage it from predators and it often tries to evade predators by outrunning them. Maras communicate through scent. Captives may saturate a site with their urine and anal gland secretions. Those sites become their preferred locations for sandbathing as they provide all members of the group with the same scent. Individuals also urinate on one another to share their scent. The maras make various vocalizations, many being very similar to those made by Patagonian maras. When approached by conspecific rival, they may emit a prolonged wheet that generally drops to a low intensity grunt. The home range varies from 33.3 to 197.5 ha, with a mean of 97.9 ha (1). The mara primarily forages on leaves and forbs in the rainy season, but also consumes woody plants, grasses, fruits seeds, and succulent species such as cacti and bromeliads, especially in the dry season. It eats nearly any available vegetation. As a common herbivore in the eastern Salta province, the mara may live in high densities and have a significant impact on the local environment. This may include overgrazing and destroying seedlings, which prevent the forest regeneration. It they may be an important seed disperser and is an important prey species for several predators, including jaguars, pumas and pampas foxes. It is host to a parasitic tick. Apart from activities related to reproduction, females and males little to no contact with one another. Even during oestrus, females may resist or withdraw from males. Females give birth to 1-5 young after @ 2 months or 77 days under the protection of thorn bush or other dense vegetation in secluded areas. Pups weigh @ 199 g at birth. They are precocial and can run at high speeds a few hours later and follow adults a few days later. They produce a “wheet” call when following and a “whine” when threatening conspecifics. In order to quickly acquire their natal group's scent, pups often roll around at the group’s urination site shortly after birth; scent marking and play help integrate juveniles into the social unit. There is little physical contact between adults and juveniles. Females nurse their young in a sitting posture in open, exposed for bouts lasting @ 5 minutes. Males generally do not participate in parental care, but seem to tolerate young and may rest and occasionally play with juveniles. Weaning begins around four weeks old. The Red List Category is "Least Concern" due to the mara's wide distribution, presumed large population and as it is unlikely to be declining fast enough to qualify for listing in a threatened category. There are no known major threats. The mara occurs in protected areas within Argentina, Bolivia and Paraguay. It is common where it is found. It has no known adverse effects on humans. It is a popular game animal throughout itsr geographic range. Indigenous hunters exploit it for food and for its pelt.

The Chacoan mara (Pediolagus salinicola) or Chacoan cavy is a relatively large South American rodent of the cavy family. They are a close relative of the better known Patagonian mara. The Chacoan mara is the sole member of the genus Pediolagus.