The feral goat is the domestic goat (Capra aegagrus hircus) when it has become established in the wild. Feral goats occur in Australia, New Zealand, Ireland, Great Britain, Hawaii, Brazil, Honduras, Lebanon, Panama, Madagascar, Comoro Islands, Mauritius, Réunion, Irian Jaya, Papua New Guinea, the Galapagos, Cuba and in many other parts of the world. When feral goats reach large populations in habitats which are not adapted to them, they may become an invasive species with serious negative effects, such as removing native scrub, trees and other vegetation. However, in other circumstances they may become a natural component of the habitat, even replacing locally extinct wild goats. Home range use and movement patterns of non-native feral goats in a tropical island montane dry landscape. Feral goats are sometimes used for conservation grazing, to control the spread of undesirable scrub or weeds in open natural habitats such as chalk grassland and heathland.
Goats were first introduced into Australia in 1788. Since then they have become feral and are now causing an estimated economic loss of $25 million per year as well as environmental degradation.