The Przewalski horse: reintroduction hazards (Part 12)

For thousands of years, Przewalski horses withstood a multitude of natural and anthropogenic hazards on the East Asian grasslands, but eventually died out under the combined pressure of environmental stressors of the 19th-20th centuries. Today, reintroduced Takhis are learning to cope with old and new hazards on their reintroduction sites. While some environmental stressors disappeared (military activitieshunting), others exacerbated (overgrazing, land degradation, desertification) and new ones emerged (e.g. road erosion, mining). Reintroduced individuals bear on their shoulders the long term survival of the species, but their relatively low numbers still make them particularly vulnerable to such threats.

Livestock overload and overgrazing

Flag of the Mongolian People's Republic

Flag of the Mongolian People’s Republic

Takhis died out under communism in the Mongolian People’s Republic in 1969 and were brought back to their native land at a time of transition to a free-market economy in the early 1990’s. Until the 20th century, the Mongolian steppe, which covers 80% of the country’s land area[1], had always been exploited by herdsmen through transhumant pastoralism, the most adequate way of using the land under the ruthless regional climate. Collectivization never suppressed this effective traditional system, but herders’ mobility on the steppes became tightly controlled from 1950[2]. As ancient pastoral customs were replaced by statutory regulations and state support increased in the form of subsidies and supplies to compensate the loss of mobility (winter forage, consumer good, transport, risk management and marketing services, etc.), nomads progressively Continue reading

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The Przewalski horse: overview of reintroduction initiatives (Part 11)

The idea of reintroducing Przewalski horses in the wild in East Asia, their last known historic range, materialized in the late 1970’s and the first release of horses took place in the early 1990’s. As of today, reintroduction was achieved in two out of three and one out of three Mongolian and Chinese proposed sites, respectively.

Hustai National Park Logo

Hustai National Park‘s symbolic logo representing Takhis

Inge and Jan Bouman, together with Mongolian scientist Tserendeleg Jachin, were the pioneers of Takhi reintroduction. They created the Foundation for the Preservation and Protection of the Przewalski Horse[1] in Rotterdam in 1977 and launched the Khustain Nuruu Project. It took over a decade to enhance the genetics of Takhis, which had become largely inbred in captivity. In 1991, the Mongolian government established Hustai National Park for the purpose of Takhi reintroduction; it was then approved UNESCO Biosphere Reserve in 2002. Situated 100 km south-west of Ulaanbataar, the 50,000 ha area (excluding buffer zones and transition areas) was chosen for the quality and abundance of its wildlife. The horses enrolled in the project were bred in Holland and kept in semi-wild reserves where they could freely interact and form social bonds before being flown to Mongolia. Between 1992 and 2000, 84 Takhis aged 3-5 landed at Hustai and the first individuals were released into the wild in the summer of 1994.

Przewalski Horses in the wild at Hustai National Park

Przewalski Horses in the wild at Hustai National Park / Credit: Kelsey Rideout

Nowadays, some 300 horses divided in 30 harems inhabit the park[2]. The objective is to reach a population of 350, which would ensure the sustainability of the species and remains Continue reading

The Przewalski horse: being wild in the wild (Part 10)

Reintroducing Takhis in East Asia is a long term process with a threefold objective: establish viable populations in parts of the horse’s historic range, restore degraded steppe ecosystems and foster socio-economic development, which in turn would guarantee the long term success of reintroduction.

When the first reintroduction program was launched in the late 1970’s, the Przewalski horses had been living in captivity for almost a century. To return to their native steppe, they first had to learn to be wild again. In addition to reducing genetic diversity, captivity had made the horses entirely dependent on men for their survival and inhibited their most basic instincts. In this context, reintroduction would be a marathon and a complex learning process for the horses.
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The Przewalski horse: walking on thin ice (Part 9)

“Twenty years ago a subspecies of wild horses, the Asian Przewalski horse, became extinct in the wild. There were still specimens in zoos but ten generations of inbreeding had weakened them and instead of infinite grasslands they knew only iron fences. The animals were merely a shadow of their former selves.”[1] It is with these words that Prince Bernhard of The Netherlands described the poor and seemingly hopeless condition of the species in the aftermath of its extirpation in the wild. Following this event, Przewalski horses experienced a dramatic population bottleneck. As the species survived through just a few captive individuals, the loss of founder genes became a terrible threat to their viability. Should they be saved, prompt action was required: breeding a healthy population through inter-zoo exchanges was a matter of urgency. From 1979, various conservation programs Continue reading

The Przewalski horse: the end of a wild journey (Part 8)

During most of the Holocene, men and Przewalski horses sustained a predator-prey relationship, and men gradually intruded, fragmented and degraded the grasslands where these animals lived. Takhis were eventually dislodged from the Mongolian and Chinese steppes though the details of this lengthy, complex and unmonitored process remain largely unknown. What is clear is that anthropogenic and climatic pressure became unbearable to the horses during the first half of the 20th century[1], depleteting the species below recovery level.

Map of last sightings

Map of the last sightings prior to 1969 / Source: Status Survey and Conservation Action Plan Equids: Zebras, Asses and Horses by the IUCN

Their last known territory prior to extinction, i.e. south-eastern Mongolia, only represented a small fraction of their much broader historic range. Yet, even there, the horses were not at rest from human presence and activities and had to retreat to areas of the Gobi Desert, which provide poorer and scarcer vegetation and water holes year round. The horses were ill-adapted to this harsher environment[2] and their situation was further aggravated by the occurrence of unusually rough climatic events around this time and by poaching, in violation of the horse hunting ban of 1926. The species’ resilience quickly eroded as bands became smaller and sparser. Large groups were still commonly encountered in the early 1940’s, but by the end of the decade and during the next one fewer individuals were occasionally sighted in the region of Tachijn-Shar-Nuru (meaning the “yellow mountain of the wild horse”), south of the Mongolian Altai, on the border with Xinjiang[3] (see map). The end was near.

The Mongolian scientist N. Dovchin was the last witness to provide an official report of a wild living Takhi in 1969: he spotted a lone stallion near gun-Tamga, a natural spring situated in the same area as the previous sightings (see map). All attempts to locate Przewalski horses in this area and other parts of their known 20th century Mongolian and Chinese range were unsuccessful after this date, which became the official year of the species’ extinction in the wild.


Continue reading about the Przewalski horse: Part 1 I Part 2 I Part 3Part 4 I Part 5 I Part 6 I Part 7 I Part 9 I Part 10 I Part 11 I Part 12


REFERENCES – [1] Przewalski’s Horse: The History and Biology of an Endangered Species, by Lee Boyd, Katherine A. Houpt, 1994, pp 15-16. [2] Przewalski’s Horse: The History and Biology of an Endangered Species, by Lee Boyd, Katherine A. Houpt, 1994, pp 15-16. [3] Status and Action Plan for the Przewalski’s Horse, S. Wakefield et al., in Equids: Zebras, Asses, and Horses, Edited by Patricia Des Roses Moehlman, IUCN/SSC Equid Specialist Group IUCN, 2002, p. 83.

The Przewalski horse: the lethal transformations of the East-Asian steppe (part 7)

Concurrently to being hunted and otherwise severed from the wild, Przewalski horses were indirectly impacted by the progressive transformations of East Asian drylands throughout the Holocene period under the combined influence of various natural and anthropogenic factors[1], some of which are briefly discussed below.

East-Asian drylands

Map of East Asian drylands established based on data from the map “Land cover map of Dryland East Asia (DEA)” available here / Blank source map available here

Agricultural development and regional population growth

Domestication of most animals and plants took place between 10,000 to 5,000 years ago[2]. Animal husbandry and cultivation were broadly adopted in Eurasia[3] although greatly varied in time, space and intensity. On East Asian drylands (see above map), particularly grasslands where the horses lived, animal husbandry dominated agriculture over the past 5,000 years; the harsh climate and low soil fertility of such regions[4] generally made cultivation difficult.

As population grew, so did agriculture, but contrasting trends in population growth resulted in different levels of agricultural intensification on the vast drylands. Continue reading

The Przewalski horse: Potential historic range (Part 6)

The goal here is not to draw the horses’ precise range at any given time during the Holocene, which is rather impossible, but to estimate their potential presence on the steppes over the past 4,000 years based on the written sources quoted in Part 4 and Part 5, the list of which is probably not exhaustive. The account of the Machurian mass hunt cannot be used due to the lack of spatial indications and the immensity of the Manchu empire in c. 1650.

The various geographical locations matching the written sources (in color) are superimposed on the borders of East-Asian drylands (in wine color) which encompass areas of prime Takhi grassland habitat. A detailed map of the vegetation contained within these border is available here.

The maps are shown in chronological order.

These various sources and corresponding maps hint at a widespread Takhi presence on the East-asian steppe, beyond in areas of Southern Siberia and possibly in portions of the Shang Civilization’s territory during a substantial part of the Holocene.


The original source map for these various maps is available here. The maps were established based on the following sources:


Continue reading about the Przewalski horse: Part 1Part 2 I Part 3 I Part 4 I Part 5 I Part 7 I Part 8 I Part 9 I Part 10 I Part 11 I Part 12