Goat
Capra hircus
Feral goats (Capra hircus)
A convenient livestock animal for early European settlers, the goat has become one of the most environmentally destructive feral animals in Australia.
Introduced to Australia with the First Fleet in 1788, the goat was valued by settlers for its meat and milk, with some breeds also providing mohair.
On Queensland's offshore islands, goats were released as a source of food for lighthouse keepers.
Its ability to thrive on rough grazing and also to reproduce rapidly endeared this animal to European settlers.
But some of these goats were released or escaped, forming feral herds. This animal now causes immense environmental damage and is found in Queensland, New South Wales, South Australia and Western Australia.
What does it look like?
Distinctive in appearance, the goat is relatively small. Males weigh about 40kg, females about 27kg.
Both the male and female goat have distinctive curved horns. Their coat varies widely in colour, and can be quite shaggy depending on the breed.
Where does it live?
Feral goats live in rocky or hilly country in semi-arid rangelands.
Very mobile, the goat travels freely through most fences in pastoral areas and easily invades areas from which it has been removed.
They like Australia's dry pastoral areas used for sheep grazing because water is available here and there are few dingoes.
What does it eat?
The goat is a herbivore and eats most plant matter, including leaves, twigs, roots, fruits and bark.
It likes trees and shrubs more than grass and will try and get the highest quality food. It needs to drink during dry spells.
The goat eats most plants in pastoral areas, even plants that are avoided by sheep and cattle.
How does it breed?
Goats become sexually mature at an early age and usually have one or two kids each pregnancy. Gestation is five months.
With a regular supply of food, many feral goats can have two litters within a year. Females with a kid are often pregnant.
Without control measures, a goat population can increase by 75 percent in a year.
Impact
Early pastoralists, townspeople and miners took the goat with them into inland Australia. During the 19th century, sailors also released many goats onto islands and the mainland for emergency food supplies.
Feral herds were set up and goats now compete with native animals and domestic livestock for food, water and shelter.
Goats have had a major impact on native plants and cause damage to habitat and natural pasture. Estimates of goat populations vary widely with a total population possibly 2-3 million.
In very high numbers, the goat is environmentally devastating. It eats nearly all plant life below 1.8m.
Its hooves break the soil which, combined with destroyed plant life, makes the soil more vulnerable to erosion.
Goats have caused much damage on Queensland islands. Eradication programs have been implemented on some islands, including Moreton Island.
The goat has been blamed for the decline of native animals such as the yellow-footed rock-wallaby. When forced out of rock shelters by the goat, the yellow-footed rock-wallaby is easy prey for foxes and wedge-tailed eagles.
The goat can also carry many internal and external parasites, some of which can affect sheep. It also carries foot rot which is very hard to remove from sheep if goats are nearby.
How can it be controlled?
Goat populations are kept under control to some extent through mustering, trapping and shooting. Where common, the dingo can also adequately control the goat.
But high rates of reproduction and the goat's mobility means control is difficult. If the goat was to ever reach its full reproductive potential, it would breed in numbers that would turn most of its habitat to near desert.
Thanks to control measures, this hasn't happened. In fact, the goat is one of the few feral animals for which eradication can be considered.
As goats join herds, isolated groups on islands or surrounding farmland can be destroyed at reasonable cost.
A technique called 'Judas' goat is used to track down feral goat herds. For this, a radio transmitter is attached to a trapped goat, which then leads a hunter to a feral goat herd.
This is far more effective than people trying to track down a herd and allows a hunter to find the last pockets of a goat population.
Last updated: 24 August 2006