It is believed that there are between 13 million and 23 million feral pigs spread across Victoria, New South Wales, Queensland and Northern Australia.
Feral pigs need water daily, so they are usually found close to water.
They reproduce quickly as young pigs reach sexual maturity at around seven to 12 months. They can produce one or two litters each year.
Feral pigs are one of Australia's most serious feral pests.
The key threats from feral pigs are predation, habitat destruction, competition and disease.
Pigs root for food - uprooting the ground for plant material - which is very destructive to the environment.
Rooting may cause any or all of the following impacts:
- disrupt the seed bank
- disturb vegetation
- change the soil composition
- spread weeds
- spread the seeds of exotic plants
- increase erosion and soil sedimentation
- destroy the habitat of native species.
Pigs compete with native species for food as they eat a variety of plants, small animals and invertebrates.
Pigs will trample and hunt for eggs, which has impacted some native turtles and is assumed to affect the eggs and young of some birds.
Feral pigs can cause damage to farms by destroying crops, damaging irrigation systems and infrastructure and reducing seedling recruitment.
They are responsible for large losses of sugarcane and have been known to kill and eat a large number of newborn lambs.
They can also spread diseases including brucellosis, psuedorabies, leptospirosis, foot-and-mouth disease and Japanese encephalitis, and the fungus Phytophthora cinnamomi.
There are a number of ways to control feral pigs including any of the following:
- baited trapping - this is most successful for small numbers if traps are placed around waterholes
- aerial culling
- poison with 1080 - this can be effective for small numbers, though it is hard work, time consuming and there is a risk of poisoning protected animals
Last updated: 18 April 2016