Pig
Sus scrofa
Feral pig (Sus scrofa)
With coarse hair and solid build, the feral pig is one of Australia’s most destructive
environmental and agricultural pests.
European settlers introduced the pig for food. Often allowed to roam free, it was not long before this animal had established populations in the wild.
The feral pig is now found in every state of Australia except Tasmania, causing widespread damage to natural ecosystems.
What does it look like?
A male pig can weigh up to 175kg, a female 110kg. If a feral pig is a colour apart from black, it is probably a cross-breed with domestic stock.
The feral pig has smaller and narrower hindquarters than domestic breeds. Its coarse mane bristles when the animal is stressed.
Where does it live?
Pigs are found in most habitats, except for dry inland areas. This is because the pig needs a reliable supply of food, water and shelter to survive.
Pig group sizes can vary depending on environmental conditions and control measures. In north Queensland, groups can number more than 60!
What does it eat?
Pigs eat plants and meat and are opportunistic feeders. They eat mostly grass but they will also much on fruit, roots, beetles, reptiles, crocodile eggs, young rabbits and other small animals.
The pig needs to drink daily in hot weather.
How does it breed?
Pigs breed throughout the year in favourable conditions. Breeding peaks from May to October.
Females can breed from seven months of age and have one or two litters a year of four to six piglets.
The female will build a nest of grass and tunnel inside to give birth. A lot of piglets can die, depending on food and weather.
But this doesn’t affect numbers in the long term, as pigs are sometimes able to double their population in one year!
Impact
The feral pig damages natural habitats through wallowing and rooting for food in watercourses and swamps.
It does this to keep cool in hot weather, but the pig destroys natural plants that prevent erosion and provide food and nesting sites for native animals.
An aggressive competitor for food with native animals in tropical rainforests, the pig is also an agricultural pest.
The feral pig competes with domestic livestock for food and damages crops such as cereal, sugarcane and corn. It also damages fences in some areas.
In Queensland, pig damage can be seen in many national parks.
It eats young lambs, removing up to 40 percent of livestock in some areas. This costs the sheep industry millions of dollars a year.
Disease is a concern, as pigs in many parts of the country are carriers of Murray Valley encephalitis and Ross River fever.
If any exotic diseases entered Australia, the pig could cause severe problems as an infectious reservoir or transmitter of disease.
Pigs can be dangerous animals! If you encounter one in the bush, stay well back.
How can it be controlled?
Shooting, mustering, trapping and poisoning are used to control feral pigs.
Feral pigs are used for their meat with exports to European countries. Landholders often leave pig traps permanently around signs of pig activity.
The dingo acts as a predator in Queensland, the Northern Territory and Western Australia, but it’s not known whether pig numbers are limited.
Unfortunately, feral pigs can recover from control techniques quickly because of their high reproductive rate. Some people’s activities are also making things worse.
Some hunters have even deliberately released piglets and young pigs into scrub in rural areas! This has not helped control efforts and pig distribution has increased rapidly since the 1970s.
Research is currently determining best practice management and control techniques which will help to get rid of this destructive pest.
Last updated: 24 August 2006
