The Onager (Equus hemiomus onager) is listed as Critically Endangered A3bcd as there is a possibility of a 90% population reduction within 3 generations (c. 24 years; 7.5 years is one generation) due to climate change and the risk of political unrest, both of which will impact access to water and forage. The current population increase is due to human intervention in the form of legal protected status, occurrence in a protected area, and provision of supplementary food and water. If any of these things were to change, the population would quickly reduce. 
This subspecies would also be considered Vulnerable under D1, as there are currently <1,000 mature individuals in 1 location.

The only population of onagers (Equus hemionus onager) resides within the Bahram-e-Goor Protected Area in southern Iran. The onagers are primarily found in the Qatrouiyeh National Park, which is within the Bahram-e-Goor Protected Area, exhibiting free movement between the park and the protected area (Esmaeili et al. 2024). Occasional and seasonal movement of small groups of onagers into farmlands surrounding the protected area, extending as far as the Qarreh Tappe No-hunting area (which overlaps Bahram-e-Goor and extends up to 50 km away) in Yazd Province and Shahr-e-Babak in Kerman Province has been reported (personal comm. Iranian Department of Environment).

Previously the onager had a widespread distribution in Fars, Yazd, Isfahan, and Kerman provinces and was historically distributed in the following locations: Herat, Marvast, Bafgh, Mehriz, Taft, and Abarkouh in Yazd Province, Shahrebabak in Kerman Province, Shahreza and Khoor-o-Biabanak in Isfahan Province, and Izadkhast, Abadeh, Bavanat, Shiraz, Sepidan and Neyriz in Fars Province (Nehir et al. 2012). 

The indigenous Asiatic wild ass population in the Touran Biosphere Reserve, along with the limited number of reintroduced animals in the Kalmand Protected Area, Siah-Kooh NP, and Kavir NP (all originating from the Touran Biosphere Reserve), are recognized as natural hybrids of E. h. onager and E. h. kulan (Kaczensky et al. 2018). By no means should the importance of the natural hybrid populations of E. h. onager and E. h. kulan in north-central Iran seen as inferior to the “pure” subpopulations / ecotypes; in the past these populations were continuous but had to adapt to different ecological drivers over the large expanse of their range.

Equus hemionus onager exists as a single autochthonous population primarily located within the Qatrouiyeh National Park and the surrounding Bahram-e-Goor protected area in south-central Iran. Some individuals from this population are occasionally found seasonally in the adjacent Qarreh Tappe No-hunting area in Yazd Province and Shahr-e-Babak plains in Kerman Province. The population in Bahram-e-Goor was estimated at 1,131 individuals in 2022, with 20 to 50 individuals in the adjacent protected areas in 2023 (Iranian Department of Environment pers. comm. 2023).

In 2023 the Bahram-e-Goor population was estimated to number approximately 1,200 onager (720 mature individuals – assuming 60% mature individuals, see E. hemionus assessment for justification). This population has exhibited a positive trend in growth since 1997, notably following enhancements made to the protected area's core zone, which was designated as Qatrouiyeh National Park in 2008. The intrinsic growth rate (r) from 1995 to 2021 was 0.08, based on annual total counts conducted by the Iranian Department of Environment (Esmaeili et al. 2023a). The total population size of onager in Bahram-e-Goor increased from around 100 in 1997 to around 1,200 in 2023. A population model projected an increasing population over the next 30 years incorporating a maximum survival rate for adult age class. Nevertheless, if for any reason the survival rate of mature individuals drops then sustainability of the population will be challenged (Nowzari 2011, Nowzari 2019). 

Using distance sampling over two consecutive years (2009-2010) in Qatrouyeh National Park, the 326 km² core area of the Bahram-e-Goor population, the onager population was estimated at 302 (95% CI 213–429; Nowzari 2011), which is a much higher concentration that in the rest of the PA. A population model projected an increasing population over the next 30 years incorporating a maximum survival rate for adult age class (Nowzari 2011). The Department of Environment’s rangers count the population each year by direct observation (attempting a total count). Monitoring of the population over 10 years (2008-2018) showed an increasing population, with a population growth rate r of 0.09 and 0.14 during 1998-2008 and 2008-2018, respectively (Nowzari 2019). Comparing these Distance sampling estimates with those reported previously based on total counts, suggests an expanding population for QNP. However, the model predicted that if for any reason the survival rate of mature individuals drops then sustainability of the population will be challenged (Nowzari 2019).

About a 13% decline in the extent of suitable habitats (accounting gains and losses of habitats) by the year 2050 is expected due to climate and land use change based on a modelling study (Rezvani et al. under review).

Onagers occur in desert and semi-desert habitat, primarily within the 4,100 km² Bahram-e-Goor protected area (PA). Bahram-e Goor PA is a shrub-steppe habitat characterized by patches of short-sward grasses that grow in early spring and dry up soon afterward. All onagers irrespective of age, sex or reproductive state, disproportionately frequent hill-valley habitats on windy as well as cloudy-rainy days, especially during winter months. Access to valleys appears to reduce the impact of wind and rain during the coldest periods (Nowzari et al. 2013).

Onager space use in the Bahram-e Goor Protected Area is highly influenced by the presence of livestock (Esmaeili et al. 2024, Rezvai et al. 2024). Onagers exhibit a shift in their resource selection between daytime (when livestock is present) and nighttime (when livestock is in enclosures). Within Qatrouiyeh National Park (which constitutes the 326 km² core of Bahram-e-Goor PA), onagers typically select areas close to water resources (Esmaeili et al. 2024).

Fecundity rate of females varied from 0.23 to 0.33 over two consecutive breeding years suggesting that females do not get pregnant every year; the sex ratio was close to 1 (48:52) (Nowzari et al. 2012). The survival rate of foals and yearlings estimated at 40% and 86% respectively indicating that the most critical part of onager's life is the first year (Nowzari et al. 2012).

Threats to the Onager include illegal hunting for meat and competition with livestock, primarily outside of protected areas. Crop raiding by Onager results in negative attitudes of some locals and potentially retaliation killings (Esmaeili et al. 2019). Crop raiding intensifies during dry seasons and dry years, occurring primarily at nighttime in the farmlands adjacent to the national park (Esmaeili et al. 2023b; Esmaeili et al. 2024). Water is scarce in Bahram-e-Goor and onager are increasingly dependent on artificial water points. A higher frequency of and/or prolonged periods of drought may pose a threat to the population due to lack of water and pasture availability, especially in light of competition with livestock. Climate change is likely the most important threat as it will exacerbate threats of limited availability of water and pasture competition with livestock. In addition to lack of water, faecal coliform levels were higher than the standard limit in all water sources in QNP. Infection by faecal coliform causes diarrhoea and excretion of watery faeces and gastrointestinal diseases in onagers and eventually their death (Khaksar and Nowzari, in press).

Upgrading the core zone of Bahram-e-Goor protected area to Qatrouiyeh National Park and providing water supplies and occasional supplementary forage resulted in an increase of the onager population. In contrast, the large adjacent Bahram-e-Goor protected area provides limited suitable habitat for onagers (Rezvani et al. 2024), due to the presence of livestock and insufficient anti-poaching patrols. As a result, the onager population is concentrated in Qatrouyeh National Park which constitutes only around 8% of Bahram-e-Goor PA (Esmaeili et al. 2024). Onager are currently attempting an expansion into adjacent protected areas towards the north (Rezvani et al. 2024), but this triggers concerns over conflicts with local people over crop raiding (Esmaeili et al. 2019) and Asiatic wild ass – vehicle collisions (Mohammadi et al. 2023). 

Competition with livestock, poaching, land conversion, droughts, isolation of the populations by transportation infrastructure and urban development, and lack of security in the movement routes of the species were recognized as the most important factors contributing to extinction of the onager populations where they were historically distributed in Yazd, Kerman, Isfahan, and Fars provinces (Nehrir et al. 2012).

Although the species is fully protected in Iran, some illegal trade seems to happen primarily on a national level and stems from poaching for meat and bone marrow fat, which like liver, is believed to have apparent medicinal properties. Illegal off-take, including retaliation killing for damages on agricultural plots, has been identified as a key threat outside of Qatrouiyeh National Park (Esmaili et al. 2019, 2023b).

This subspecies is listed on CITES Appendix II. The taxon has full national protection and occurs largely within protected areas. There are increasing efforts to improve monitoring of the population status and understand persisting threats. In Iran a National Action Plan was developed for the conservation of Asiatic Wild Ass in 2020. However, the plan has not yet been implemented.