The pampas deer is a South American herding deer that is critically endangered. Due to high genetic variability, pampas deer are among the most polymorphic mammals. Their hide is made up of brown fur that is lighter on the inside of their legs and underside. They have white spots under the throat and on the lips, and their coloration does not change with the season.
Origin of the species and description
Pampas deer belong to the New World deer family, which is another term for all South American deer species. Until recently, only three subspecies of pampas deer have been found: O. bezoarticus bezoarticus found in Brazil, O. bezoarticus celer in Argentina, and O. bezoarticus leucogaster in southwestern Brazil, northeastern Argentina, and southeastern Bolivia.
The existence of two different subspecies of pampas deer endemic to Uruguay, O. bezoarticus arerunguaensis (Salto, northwestern Uruguay) and O. bezoarticus uruguayensis (Sierra de Agios, southeastern Uruguay) has been described based on cytogenetic, molecular and morphometric data.
Video: Pampas deer
Male pampas deer are somewhat larger than females. Free males reach a length of 130 cm (from the tip of the muzzle to the base of the tail) with a length of 75 cm at shoulder level and a tail length of 15 cm. They weigh approximately 35 kg. However, data from captive-bred animals indicate several smaller animals: males are approximately 90-100 cm long, 65-70 cm shoulder height, and weigh 30-35 kg.
Fun fact: Male pampas deer have a special gland in their hind hooves that produces an odor that can be detected at a distance of up to 1.5 km.
The antlers of the pampas deer are medium in size compared to other deer, hard and thin. The horns reach 30 cm in length, have three points, a point of eyebrows and a back, and a longer forked branch. Females reach 85 cm in length and 65 cm in shoulder height, while their body weight is 20-25 kg. Males tend to be darker than females. The males have horns while the females have whorls that look like mini horn stubs. The upper prong of the male’s horn is divided, but the anterior main prong — only one solid part.
Appearance and Features
The predominant color of the upper parts and limbs of the pampas deer — reddish brown or yellowish gray. The muzzle and tail are slightly darker. The color of the hair on the back is richer than towards the limbs. Creamy areas occur in tufts on the legs, inside the ears, around the eyes, chest, throat, on the underside of the body, and on the underside of the tail. There is no noticeable difference between the summer and winter colors of pampas deer. The color of newborn individuals & # 8212; chestnut with a row of white spots on each side of the back and a second line from the shoulders to the hips. The spots disappear by about 2 months, leaving a rufous juvenile layer.
Interesting fact: The light brown coloration of the pampas deer allows it to blend in perfectly with the environment. They have patches of white around the eyes, lips and along the throat area. Their tail is short and fluffy. The fact that they also have a white spot under their tail explains why they are often confused with white-tailed deer.
The pampas deer is a small species with slight sexual dimorphism. Males present small, light, three-pronged antlers that go through an annual shedding cycle in August or September, with a new set grown by December. The lower anterior tooth of the horn is not divided, unlike the upper one. In females, curls of hair look like tiny horn stumps.
Males and females have different positions during urination. Males have a strong odor secreted by glands in their hind hooves, which can be detected at a distance of up to 1.5 km. Compared to other ruminants, males have small testicles compared to their body size.
Where do pampas deer live?
The pampas deer once inhabited the natural grasslands of eastern South America, located between 5 and 40 degrees latitude. Now its distribution is limited to the local population. Pampas deer are native to South America and are also found in Argentina, Bolivia, Brazil, Paraguay, and Uruguay. Their habitat includes water, hills, and grass that is tall enough to hide deer. Many pampas deer live in the wetlands of the Pantanal and other areas of the annual flood cycle.
There are three subspecies of pampas deer:
- O.b. bezoarticus — native to central and eastern Brazil, south of the Amazon and Uruguay, and is a pale reddish brown;
- O.b. leucogaster — lives in the southwestern region of Brazil to the southeastern part of Bolivia, Paraguay and northern Argentina and is yellow-brown in color;
- O.b. celer — lives in southern Argentina. It is an endangered species and the rarest pampas deer.
The pampas deer occupies a wide variety of open grassland habitats at low elevations. These habitats include areas temporarily flooded with fresh or estuarine water, hilly terrain, and areas with winter drought and no permanent surface water. Much of the original pampas deer population has been modified by agriculture and other human activities.
Now you know which continent the pampas deer lives on. Let’s find out what it eats.
What does a pampas deer eat?
Pampas deer’s diet usually consists of grasses, shrubs, and green plants. They don’t consume as much grass as they browse, which are twigs, leaves, and shoots, as well as forbs, which are flowering, large-leaved, soft-stemmed plants. Pampas deer usually migrate to where the food source is greatest.
Most of the vegetation that pampas deer consume grows on moist soils. To see if deer compete with cattle for food, their excrement was studied and compared to that of cattle. In fact, they eat the same plants, only in different proportions. Pampas deer eat less grass and more grass (flowering, soft-stemmed broad-leaved plants) and also browse shoots, leaves, and twigs.
During the rainy season, 20% of their diet consists of new herbs. They move around for the availability of food, especially flowering plants. The presence of cattle increases the amount of sprouted grass that pampas deer prefer, furthering the idea that deer do not compete with cattle for food. Contrasting studies show that pampas deer avoid areas where cattle live, and when cattle are not present, home ranges are much larger.
Character and Lifestyle Features
Pampas deer — they are social animals that live in groups. These groups are not segregated by sex, and males move between groups. There are usually only 2-6 deer in a group, but in good feeding areas there can be many more. They don’t have monogamous couples and don’t have harems.
Pampas do not defend territory or mates, but show signs of dominance. They show dominance by raising their heads and trying to keep their side forward and using slow movements. When males challenge each other, they rub their horns into the vegetation and scrape them along the ground. Pampas deer rub their scent glands on plants and objects. They don’t usually fight, but just squabble with each other, and usually bite.
During the mating season, adult males compete with each other for estrous females. They destroy vegetation with their horns and rub scent glands on their heads, plants, and other objects. Aggression is manifested in pushing the horns or waving the front paws. Frequent collisions occur between males of the same size. There is no evidence of territoriality, long-term pairing, or harem formation. Several males may chase a receptive female at the same time.
Fun fact: When the pampas deer feel threatened, they hide low in the foliage and hold on, then jump 100-200 meters. If they’re alone, they might just slip away quietly. Females will pretend to limp next to males to distract a predator.
Pampas deer usually feed during the day, but are sometimes nocturnal. They are very curious and love to explore. Deer often stand on their hind legs to get food or see things. They are sessile and have no seasonal or even daily movements.
Social structure and reproduction
Little is known about the mating system of pampas deer. In Argentina, they breed from December to February. In Uruguay, their mating season runs from February to April. Pampas deer have interesting courtship behaviors that include low stretching, crouching, and leaning back. The male initiates courtship with a low tension and makes a soft sound. He clings to the female and can flick his tongue at her and look away. He stays close to the female and can follow her for a long time, sniffing her urine. Sometimes the female reacts to courtship by lying on the ground.
The females separate from the group to give birth and hide the fawn. Usually only one deer is born weighing about 2.2 kg after a gestation period of more than 7 months. Newborn deer are small and spotted, and lose their spots at around 2 months of age. At 6 weeks old, they are able to eat solid food and begin to follow their mother. Fawns stay with their mothers for at least a year and reach reproductive maturity at about one year of age. Sexual maturity in captivity can occur at 12 months.
Pampas deer — seasonal breeder. Adult males are capable of mating all year round. Females are able to give birth at 10-month intervals. Pregnant females can be distinguished noticeably 3 months before delivery. Most cubs are born in the spring (September to November), although births were recorded in almost all months.
Pampas deer natural enemies
Large cats such as cheetahs and lions prey on temperate grasslands. In North America, wolves, coyotes, and foxes prey on mice, rabbits, and pampas deer. These predators help control populations of grazing animals to prevent herders from eating all the grass and other plants in the biome.
Pampas deer are threatened by overhunting and poaching, habitat loss due to disease in domestic and wild animals, agriculture, competition with newly introduced animals, and general overexploitation. Less than 1% of their natural habitat remains.
Between 1860 and 1870, documents for the port of Buenos Aires alone show that two million pampas deer skins were shipped to Europe. Many years later, when roads were laid across the South American steppes – the pampas – cars made it easier for poachers to reach deer. They were also killed for food, for medical purposes and for sport.
The settlers brought huge agricultural expansion, over-hunting, and disease to the pampas deer with the introduction of new domestic and wild animals. Some landowners set aside part of their property for the reserve for pampas deer, and also keep livestock instead of sheep. Sheep are much more likely to graze on the ground and pose a greater threat to pampas deer.
Population and species status
According to the IUCN Red List, the total population of pampas deer is about 20,000-80,000 individuals. The largest population is in Brazil, with about 2,000 individuals in the northeastern Cerrado ecosystem and 20,000-40,000 individuals in the Pantanal.
There are also estimated populations of pampas deer species in the following areas:
- in the state of Parana, Brazil — less than 100 individuals;
- in El Tapado (Salto Department), Uruguay — 800 individuals;
- in Los Ajos (Department of Rocha), Uruguay — 300 individuals;
- in Corrientes (Department of Ituzaigo), Argentina — 170 individuals;
- in the province of San Luis, Argentina — 800-1000 individuals;
- in Bahia de Samborombom (Province of Buenos Aires), Argentina — 200 individuals;
- in Santa Fe, Argentina — less than 50 individuals.
According to various estimates, about 2,000 pampas deer remain in Argentina. This general population is geographically divided into 5 isolated population groups located in the provinces of Buenos Aires, San Luis, Corrientes and Santa Fe. The population of subspecies O.b. leucogaster found in Corrientes is the largest in the country. This subspecies has very few individuals in Santa Fe, and is not present in the other two provinces. In recognition of its importance, the province of Corrientes has declared the pampas deer a natural monument, which ensures not only the protection of the animal, but also the protection of its habitat.
The pampas deer are now classified as “endangered”, which means that they may become endangered in the future, but for now there are enough of them that they do not qualify as a threatened species.
Pampas deer conservation
The conservation team at the Ibera Natural Reserve in the Argentinean province of Corrientes is working to reverse the prevailing trends in habitat and species loss in the region by conserving and restoring local ecosystems and their characteristic flora and fauna. First on the priority list is the reintroduction of locally extirpated pampas deer to the Iberian pastures.
The Ibera Pampas Reindeer Rehabilitation Program has two main goals: firstly, to stabilize the existing population in the Aguapey region, which is adjacent to the reserve, and secondly, to re-establish a self-sustaining population in the reserve itself, thereby expanding the overall range of the deer. Since 2006, periodic censuses of the pampas deer population have been conducted to estimate the distribution and abundance of the species in the Aguapey area. At the same time, promotions were developed, meetings with cattle owners were organized, brochures, posters, almanacs and educational CDs were developed and distributed, and even a puppet show for children was organized.
With the help of Argentinean flora and fauna, a 535-hectare reserve dedicated to the conservation and distribution of the pampas deer. The reserve was named Guasutí Ñu, or Land of the Deer in the native Guarani language. This is the first protected area dedicated exclusively to the conservation of pampas deer in the Aguapeia region.
In 2009, a team of veterinarians and biologists from Argentina and Brazil completed the first capture and movement of pampas deer in Corrientes. This has served to restore the population of the species in the San Alonso Reserve, on a plot of 10,000 hectares of high-quality pasture. San Alonso is located in the Ibera Natural Reserve. The deer population here in San Alonso is the fifth known species population in the country. With the addition of San Alonso to the country’s protected lands, the area designated for strict conservation in Argentina has quadrupled.
The pampas deer used to be a frequent visitor to the grasslands of South America. In modern times, however, these flexible, medium-sized deer are limited to only a handful of communities throughout the geographic area. The pampas deer is native to Uruguay, Paraguay, Brazil, Argentina and Bolivia. Pampas deer numbers are declining and many factors are possible causes, including diseases infested by farm animals, over-hunting, and minimization of their habitat due to agricultural expansion.