The term "feral" means an animal that had been domesticated but has escaped into the wild and is not causing a problem. We sometimes refer to foxes as "feral" but this is a misnomer as the fox had never been domesticated or 'tamed'. There are feral populations of pigs, cats, dogs, goats, deer and camels in the wild in Australia. A term that captures all of these and the fox is "introduced species", although not all introduced species are causing problems. It is true to say, however, that introduced animals have changed the Australian environment forever.
Dingo Canis lupus dingo
The dingo was the first feral animal in Australia, brought to Australia by Indonesian seafarers. Dingoes became widespread due to their agile, cunning nature making them highly successful hunters. One of the main causes of the Tasmanian Devil disappearing from mainland Australia was the dingo's hunting skills. Tasmanian devils are mainly carrion feeders, however the fierce competition for food from the dingo effectively banished the Tasmanian devil to Tasmania.
Fox Vulpes vulpes
Foxes were deliberately released in Australia in the 1860s and 1870s . They were released in Victoria for hunting. Their success was on the back of the rabbit, which had been introduced several years before. Foxes are well known for their intelligence. The fox population in Australia today has been estimated at an incredible 30 million! That's about 10 million more foxes than people. Foxes are estimated to kill 7 billion animals per year in Australia. Predation by foxes is listed by the New South Wales National Parks and Wildlife Service as a Key Threatening Process for biodiversity. The fox is the largest terrestrial carnivore on mainland Australia. Not only does the fox kill and eat wildlife but, depending on the season, they eat ripe fruits and insects which means there is less food for native mammals and birds to feed on. Both sexes in the fox are sexually mature by the age of one year, which means it does not take long for populations of the fox to grow.
Cat Felis catus
Cats are thought to have been in Australia for several hundred years. They may have been released on the northwest coast in the 1600's by Dutch seafarers. They were kept on boats to keep down rodent numbers during long trips. Feral cats and also domestic cats do a great deal of damage to our Australian wildlife. If a cat is abandoned or runs away it does not take long for them to breed with other cats. The cats then hunt and kill wildlife for food.
Many cat owners do not know what their cats get up to during the day and, especially, at night. Domestic cats are also a problem as cats have the hunting instinct and will never lose it.
Cats are keen, agile hunters and easily hunt and kill our unsuspecting native birds and mammals. Feral cats have proven very hardy animals being found in all areas of Australia even in the desert. Approximately 30 years ago around 200 cats were shot at a tip in Central Australia, due to the drought they were searching for food. Studies have shown that up to 7 species of reptile have been found in a cat's stomach at one time. They feed on invertebrates, reptiles, amphibians, mammals and birds. This is disturbing as the animals the cat is feeding on is taking food from the native animals and disrupts the food chain. Please keep your cat inside as much as possible and especially overnight.
If your cat must be outside at some time, please ensure it has a bell around it's neck so that the small creatures that it hunts at least have some warning they are being stalked by a cat.
Rabbit Oryctolagus cuniculus
Rabbits are cute but destructive. They were introduced from Europe around 1860 where it was a controlled herbivore. The rabbit is a herbivore which means it eats plant material and vegetation. It grazes primarily on grass and its populations usually are increased near water. Due to the number of rabbits and their grazing behaviour, rabbits are a problem due to their changing plant community composition. Although foxes, cats and myxomatosis have had an affect on rabbit numbers, there would need to be an 85% mortality rate of rabbits to neutralise their massive reproductive rate.