We are familiar with the two major categories of animals - domestic and wild animals. Domestic animals like cats, dogs, cows, sheep, goats and few others are tamed by humans for different purposes. On the other hand, we can see wild animals only at zoos or forests. There is yet another species called feral animals popular especially in Australia. There are about 51 bird species and 18 mammal species that have established significant feral population.
Feral animals are those animals that were once domesticated but not anymore. They start to live in the wild like wild animals. Domesticated animals become feral when they are abandoned or they escape on their own. They start to survive in the wild without assistance. They establish a self sustaining population independent of humans. Feral animals normally include livestock such as goats, pigs, cats, wild horses and dogs.
Feral animals become invasive creatures posing threat to the natural environment. Some are cryptic, largely nocturnal and hard to catch which means their population cannot be controlled. They may occupy any habitat ranging from rainforests to desert. They speed up soil erosion depleting natural vegetation, increasing the spread of weeds. Thereby they tend to remove food and shelter of other native animals. Certain animals can carry the same common diseases as domestic animals. Feral animals are capable of hunting the native farm animals.