Sex-specific survival rates with females living longer than males were evident in kulan and onager but not in kiang and Somali wild ass, pointing towards different life-history strategies even among closely related taxa.
We investigate three Asiatic wild ass subspecies (kulan, Equus hemionus kulan, onager, E.
These studbooks include data on > 1800 kulan, 900 onager, 350 kiang, and 620 Somali wild ass individuals.
Accordingly, first reproduction took place at an age of three years in kulan males, two years in kulan females, three years in onager males, two years in onager females, two years in kiang males, three years in kiang females, four years in male and two years in female Somali wild asses.
Reproductive phase tended to be negatively related to post-reproductive phase in kulan and onager, and to birth rate within the reproductive phase in one out of four cases (plus two according tendencies).
Additionally, birth rate throughout the entire lifespan was significantly negatively associated with the length of the post-reproductive in kulan and onager.
Unfortu-nately, the wild equines of the Mongolian steppe--such as Przewalski's horse, or kartag (Equus przewalskii), and the kulan
Mongolian ass (Equus hemionus hemionus)--are in danger of extinction.