Onagers are reported to have a bad temperment, which makes them unsuitable as work-a-day domestic animals. However, the ancient Roman Legions are thought to have used these animals to pull their war machines. Onagers were previously considered a species, Equus onager, but have since been included as a subspecies of kulans, Equus hemionus.
Equus hemionus onager has strong senses with an extremely keen sense of smell. Like other members of the genus Equus, onagers have vocal, tactile and chemical communication. In addition, visual signals may be important.
Communication Channels: visual ; tactile ; acoustic ; chemical
Perception Channels: visual ; tactile ; acoustic ; chemical
IUCN estimates 144 onagers remaining with the rate of decline at 28% over the last three generations.
US Federal List: endangered
CITES: appendix ii
Although there is no apparent direct negative economic impact that this species has on humans, it is possible that these wild asses compete with livestock for water and scarce food resources.
Onagers have been hunted by humans in the past for their flesh and hides. However, in 1971, E. hemionus onager became a protected species in Iran and hunting it is prohibited year-round.
Positive Impacts: food ; body parts are source of valuable material
Grazing by E. hemionus onager impacts vegetation communities in which they live.
Onagers are herbivores that feed on the scarce plant life in the desert. Foods of these animals include grasses, bushes, herbs and foliage. Onagers receive most of their water from their food, but must remain close to a site of open water. Grazing time for onager sis usually during the cooler part of the day such as morning and evening.
Plant Foods: leaves; roots and tubers; wood, bark, or stems; seeds, grains, and nuts
Primary Diet: herbivore (Folivore )
Onagers, Equus hemionus onager, are found from Mongolia to Saudi Arabia and as far north as southern Russia and Kazakhstan. Some also inhabit northwestern India and Tibet. They have been reintroduced in Mongolia and Iran.
Biogeographic Regions: palearctic (Introduced , Native )
The flat regions of the deserts and surrounding foothills are home to E. hemionus onager. These barren deserts are a harsh environment and receive very little rainfall each year.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: desert or dune
The maximum lifespan of E. hemionus onager is reported to be approximately 40 years. However, whether this information is based on wild or captive animals is not known.
In comparison with other Asiatic wild asses, E. hemionus onager is slightly smaller with a paler coat. Onagers have a pale sandy-red colored coat with a light brown dorsal stripe. The dorsal stripe has two surrounding white strips that blend into the lighter colored hind quarters. In addition to the dorsal stripe, onagers also have a shoulder stripe. The flanks, back and underside of onagers are white. In the winter, the coat grows longer and turns grayer and the white parts become more defined. Males and females differ only slightly outwardly, with males being only slightly larger. Males stand 1.5 meters at the shoulder and are about 2 meters in length, weighing about 250 kilograms.
Average mass: males: 250 kg.
Average length: males: 2 m.
Sexual Dimorphism: male larger
Other Physical Features: endothermic ; bilateral symmetry
Equus hemionus onager has no natural predators other than humans. This species is being driven to extinction due to hunting, competition for food and water with livestock, and loss of natural habitat. Onagers have a well developed sense of smell and can detect potential predators, such as humans, from a far distance. Onagers are also very fast, with the ability to run 60 to 70 kilometers per hour over short distances, and 40 to 50 kilometers per hour for several hours at a time.
Known Predators:
A dominant stallion mates with females in the herd. In order to assure breeding status, stallions defend the territories that females move through, with dominant stallions defending the best territories.
Mating System: polygynous
During mating season in mid-June, stallions fight each other for mating rights. Females have a short estrus period of 3 to 5 days. After a year-long gestation, mares leave the herd to give birth in a safe place. A single foal is born that stays with its mother for two years. After giving birth, both mare and foal rejoin the herd, where the mother protects her foal from danger.
Pregnancy in onagers lasts 365 to 368 days. Nowak (1999) reports that lactation in female Equus hemionus (a species of wild ass in which some authorities include onagers) nurse their young for between 1 and 1.5 years. It is reasonable to assume that onagers fall within this range. Young onagers become independent around two years of age. Females are sexually mature around the age of 2, but males, at least in E. hemionus, mature about a year later.
Breeding interval: Onager mares breed every other year.
Breeding season: Onagers usually mate in mid-June.
Range number of offspring: 1 to 1.
Range gestation period: 365 to 368 days.
Range weaning age: 18 to 24 months.
Average time to independence: 2 years.
Average age at sexual or reproductive maturity (female): 2 years.
Range age at sexual or reproductive maturity (male): 2 to 4 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous
All members of the genus Equus are fairly precocial at birth, and are able to run shortly after birth. During the first two years of a foal's life, it stays with its mother. Mares protect their foals against all dangers. Nursing lasts between 1.5 and 2 years. Although specific details on the relationship between maternal dominance status and status of offsping, it is reasonable to assume that this species is like other members of the genus. If E. hemionus onager is like other horses, maternal dominance status affects status of the young within the herd. The role of males in care of offspring has not been reported.
Parental Investment: precocial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Protecting: Female); maternal position in the dominance hierarchy affects status of young
The onager or Persian onager (Equus hemionus onager) is one of the four extant subspecies of Asiatic wild ass, although the relationships with its close relatives are in need more study to confirm its placement.The onager is a donkey-like small horse native to Iran and introduced to Saudi Arabia, where it lives in deserts foraging on grasses and branches out to eat woodier plant material in dry seasons.
The population size of E. h. onager is vastly reduced from that of 100 years ago, when it ranged throughout Iran.In 2007, a census estimated a total of about 600 individuals living in two separate and genetically isolated populations, in the small, geographically separated protected areas of Touran and Bahramgor.An additional five individuals were introduced into Saudi Arabia in 2003, but this managed population has not expanded since.In Israel, fourteen E. h. onager and E. h. kulan individuals were successfully introduced into a 4500 km2 area by the Israel Nature Reserves Authority; these individuals hybridized and the population expanded to a count of 100 individuals by 1982.Ongoing monitoring of this hybrid population examines the population increase as a function of behavior, habitat use, social system and changes in vegetation, with the purpose of establishing a management plan for these animals.About 30 captive individuals are kept in AZA institutions in North America; in 2010 the collaborative conservation association C2S2 produced two onager foals by artificial insemination of stored sperm, a first for any wild equid (The Wilds 2013).
Onagers are threatened by poaching, especially for meat, overgrazing, limited access to water and increased human activities (such as removing shrub growth on which onagers rely for food). Scientists suggest that increased understanding of basic behaviour, ecology and systematics studies to clarify the subspecies designation of E. h. onager would increase our ability to protect this population.
(Moehlman, Shah and Feh 2008; Boone 2002; Feh et al. 2002; Saltz et al. 2000 )
The Persian onager (Equus hemionus onager), also called the Persian wild ass or Persian zebra, is a subspecies[3] of onager (Asiatic wild ass) native to Iran (Persia). It is listed as Endangered,[1] with no more than 600 individuals left in the wild and only 30 individuals living within North American institutions.
The Persian onager is also simply named gur (گور) meaning "zebra" in Persian. "Onager" is from the Greek ὄναγρος (onagros), meaning "wild ass".
Sometimes, the term "onager" is reserved specifically for this subspecies.[3] However, as the whole species of the Asiatic wild ass is known simply as onager, it now also serves as the Persian wild ass's scientific name, as well (Equus hemionus onager). Information on the basic biology of the subspecies and how it differs from others is lacking, which hampers conservation efforts.[3]
Onagers used to be numerous from the Middle East to China. However, until the 19th century, their population has been reduced from several thousand to a few thousand. Currently, more than 600 Persian onagers are living in the wild.
Persian wild asses are known to inhabit mountain steppes, semidesert, or desert plains. They are usually found in desert steppes. Their largest population is found in Khar Turan National Park.
The Persian onager is listed as endangered by IUCN Red List, as it is close to extinction. Currently, poaching for meat and hides, competition with livestock, and drought are the greatest threats to this species.
Asiatic wild asses are legally highly protected; hunting them is forbidden. The European Endangered Species Programme reserved for European Association of Zoos and Aquaria is helping save the Persian onager from extinction, by breeding them in captivity and reintroducing them to their former ranges, including in new locations once inhabited by Syrian onagers in Saudi Arabia, Israel, and Ukraine.
On August 30, 2014, Iranian officials reported that three Persian onagers were born in Khar Turan National Park reserve near Shahroud in Semnan province, where it also has the largest populations of the equids.[4]
A few Persian onagers are breeding in various zoos of Europe and the Middle East, such as Chester, Whipsnade, and Yotvata. The Smithsonian Conservation Biology Institute in Front Royal, Virginia, also breeds Persian onagers, including two born in June 2015. The first ever artificial insemination of any wild equid was in this species, and resulted in two Persian Onager foals at the Wilds conservation center in Southeastern Ohio, in collaboration with experts from the Smithsonian Conservation Biology Institute.
Since 2003, Persian onagers have been introduced in Saudi Arabia, where the Syrian wild ass (E. h. hemippus) once lived. Introduced Persian onagers live in deserts foraging on grasses and branches or woodier plant material in dry seasons.[5]
In 1968, 11 Persian and Turkmenian onagers were flown from their countries to Israel in exchange for mountain gazelles. These were bred in captivity at the Hai Bar Yotvata wildlife sanctuary. Together, they bred a few Persian/Turkmenian hybrids in Israel. Offspring were introduced into the wild in the Negev Mountains area, intended to replace the local subspecies gone extinct. The introduced onagers have since established a stable population around 200 individuals.
The Persian onager (Equus hemionus onager), also called the Persian wild ass or Persian zebra, is a subspecies of onager (Asiatic wild ass) native to Iran (Persia). It is listed as Endangered, with no more than 600 individuals left in the wild and only 30 individuals living within North American institutions.
