The donkey that we all know, that intelligent and docile horse that has been used so much as a work animal in the fields, is a domestic subspecies that originally descends from wild populations.
As far as we know, there were three subspecies of wild asses. The Algerian wild ass became extinct at the time of the Roman Empire; Of the other subspecies, the status of the Nubian wild ass is uncertain. The only one we are sure of its existence in the wild is the Somali wild ass ( Equus africanus somalicus ).
The Somali wild ass is very similar in size, carriage and appearance to the domestic ass. The main feature that allows the identification of this wild subspecies is its pattern of stripes on the legs , similar to that of zebras, which is not present in any other donkey.
It is a temporary herd animal. It forms large groups for several months, which then disperse. In their disintegrated state, the small stable groups are reduced to a female and her offspring. It reproduces once every two years , the gestation lasts from 11 to 14 months and they give birth in the rainy season.
The population is distributed in northeastern Ethiopia , in the Afar and Ogaden regions, in Eritrea , in the Dankalia region, and in western Djibouti . Although some populations in Somalia are listed, there is no recent information on them, and they may be extinct. Its main habitat is arid and semi-arid shrubs and grasslands, covering a wide range of altitudes that range from endorheic environments below sea level, such as the Dallol depression, up to 2000 meters.
Currently, the census population of Somali donkeys is about 70 individuals , the most optimistic estimates indicate that it could be up to 600, of which, a third of them would be mature. This total population is divided into several smaller groups, the largest of which barely has 17 adult individuals.
In 1977, a population density of up to 30 donkeys per 100 km2 was estimated in the Yangudi-Rassa National Park. Current estimates indicate that donkeys in the same park are already extinct, and that the global population has decreased by more than 95% since then. However, although the global trend seems to continue downward, the population in Eritrea is currently stable and could start to increase.
The main threat facing the Somali wild ass is hunting for food and supposedly medicinal purposes. In some traditions, donkey bone broth is used as a supposed remedy against tuberculosis, rheumatism or back pain.
Added to hunting is limited access to drinking water and fodder. In this regard, there are two main drivers that threaten wild ass populations: competition with livestock and climate change, which is causing an increasingly pronounced desertification of the area.
The International Union for Conservation of Nature lists the Somali wild ass as a critically endangered species . Fortunately, there is a plan to try to bring this species back before it’s too late.
The European Association of Zoos and Aquariums ( EAZA , for its acronym in English) currently manages a series of recovery programs for more than 400 endangered species, one of them being the Somali wild ass. These are ex situ conservation programmes, coordinated and managed by different EAZA member zoos.
Donkey breeding is included in this program, something that the Basel Zoo in Switzerland has achieved very successfully, and has even developed a specific protocol that includes key aspects of management, nutrition and health. Many other parks in Europe, including Spanish parks, also have populations of Somali donkeys, and often provide data or even samples that are very useful in these investigations.
In breeding, it is important that the animals have as little human imprint as possible; despite this, it is not normally possible to release them into the wild: their rearing in a controlled environment makes them very vulnerable and unable to fully develop their wild behaviour.
However, the data obtained from these investigations can help conserve natural populations , encourage their breeding and even, at a given moment, provide reproductive individuals, which enrich the genetic population if necessary.
References:
EAZA. 2021. EAZA Ex situ Programs (EEPs) . EAZA.
IUCN. 2014. Equus africanus: Moehlman, PD, Kebede, F. & Yohannes, H.: The IUCN Red List of Threatened Species 2015: e.T7949A45170994 [Data set]. International Union for Conservation of Nature. DOI: 10.2305/IUCN.UK.2015-2.RLTS.T7949A45170994.en
Pagan, O. et al. 2009. Husbandry and breeding of Somali wild ass Equus africanus somalicus at Basel Zoo, Switzerland. International Zoo Yearbook , 43(1), 198-211. DOI: 10.1111/j.1748-1090.2008.00072.x
Selwo. 2022. Somali Donkey . Selwo Adventure.
Sierra, C. 2022. Collaboration in the Somali wild ass ex situ protection program in the Selwo parks [Pers. comm.