Onager Asiatic cheetahs, and possibly bears, though they may have mostly preyed only on onager foals. In India, mugger crocodiles can be great threats to onagers during migratory river crossings. Currently, the biggest predator for onagers are gray wolves. About 23% of prey proportion of gray wolves were on the Asian wild ass. However, like most equids, they are known to have antipredator protection. Groups of stallions cooperate and try to chase off predators. If threatened, onagers defend themselves and violently kick at the incoming predator. The greatest threat facing the onager is poaching for meat and hides, and in some
Onager (weapon) could be winched back again. The onagers of the Roman Empire were mainly used for besieging forts or settlements. They would often be armed with large stones that could be covered with a combustible substance and set alight. The onager was used from the 4th century AD until the 6th century AD. The late-fourth century author Ammianus Marcellinus describes 'onager' as a neologism for scorpions and relates various incidents in which the engines fire both rocks and arrow-shaped missiles. The late-fourth or early-fifth century military writer Vegetius stipulates that a legion ought to field ten onagers, one for each cohort.