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Feral populations

In some areas domestic donkeys have returned to the wild and established feral populations such as those of the burro of North America and the Asinara donkey of Sardinia, Italy, both of which have protected status. Feral donkeys can also cause problems, notably in environments that have evolved free of any form of equid, such as Hawaii. In Australia, where there may be 5 million feral donkeys, they are regarded as an invasive pest and have a serious impact on the environment. They may compete with livestock and native animals for resources, spread weeds and diseases, foul or damage watering holes and cause erosion.