Pig (feral) (Sus scrofa)

  • Photograph of the side of the head and shoulder of a black feral pig lying on the ground
    Feral pig
  • Photograph of a small group of feral pigs standing in the corner of a fenced enclosure
    Feral pigs can damage sugarcane, wheat, banana and strawberry crops

General information

The feral pig is one of the most widespread and damaging pest animals in Queensland. Feral pigs in Australia are descendants of various subspecies of the domestic pig. Accidental and deliberate releases of domestic and semi-feral pigs, and subsequent breeding have resulted in a large feral pig population.

You can participate in a national mapping project by reporting feral pig populations.

The feral pig is a declared Class 2 pest animal under Queensland legislation. It is the responsibility of landholders to control feral pigs on their land.

Scientific name

Sus scrofa

Description
  • Typically smaller, leaner and more muscular than domestic pigs with well developed shoulders and necks, and smaller, shorter hindquarters.
  • Body usually covered in sparse, coarse hair.
  • Longer, larger snout and tusks; straighter tail; smaller, mostly pricked ears; and much narrower back than domestic pigs.
  • Mostly black, buff-coloured or spotted black and white.
  • Generally shy and nocturnal, but can be active any time of the day.
  • Juveniles may be striped, while old boars (razorbacks) have massive heads and shoulders, and a raised, prominent backbone.
Habitat
  • Inhabits about 40% of Australia from subalpine grasslands to monsoonal floodplains.
  • Greatest concentrations on the larger drainage basins, and swamp areas of the coast and inland.
Distribution
  • Found in most areas of Queensland.
  • Estimated up to 24 million feral pigs in Australia.
Life cycle
  • Females and juveniles usually live in small family groups.
  • Adult males are typically solitary.
  • Produce two litters of 4-10 piglets a year in good conditions.
  • Weaned after 2-3 months.
  • Population, in good conditions, may double in 12 months.
Crops affected
  • Seed, grain, fruit and vegetable crops.
Impacts

Environmental

  • Spread weeds.
  • Degrade waterholes and wetlands.
  • Cause soil erosion.
  • Prey on a wide range of native species including small mammals.
  • Significantly impact marine turtle populations by eating eggs.
  • Can carry diseases that affect native animals.

Economic

  • Damage almost all crops from sowing to harvest.
  • Feed on seed, grain, fruit and vegetable crops.
  • Damage pastures by grazing and rooting.
  • Prey on lambs.
  • Can carry diseases and parasites that affect stock.

Social

  • Carry many diseases that affect people.
Control
  • Difficult to control in some situations.
  • Effective control requires an integrated, collaborative approach where all stakeholders participate in planning and implementation of a management plan.
  • Various control methods including shooting, poisoning, trapping and fencing with appropriate land management practices are most effective.
Trapping
  • Trapping is an important technique that is most useful in populated areas, on smaller properties (<5000ha), and where there are low pig numbers. Trapping can be particularly useful in ´mopping up´ survivors from poisoning programs. It is most successful when food resources are limited.
  • Trigger mechanisms for pig traps can be made pig-specific and therefore pose little danger to other wild or domestic animals.

Poisoning

  • Poisoning is usually the most efficient and effective control method for reducing a pig population.
  • Depending on the circumstances and bait type used, poison bait may be distributed from the air or the ground.
  • Sodium fluoroacetate (1080) is recommended, but can only be supplied through persons authorised under the Health Act. Contact your local government for more information.
  • Pre-feeding is the most important step in ground-poisoning operations. To maximise effectiveness, free feeding with non-poisoned bait should be performed for several days prior to laying poisoned baits.
  • Pig-specific feeding stations (e.g. Hoghopper) may be of use to reduce non-target species access to bait, where required.

Shooting and the use of dogs

  • Shooting pigs by helicopter is most effective where pigs exist in reasonable numbers and are observable from the air. It is usually too costly for low-density populations.
  • In the dry tropics, aerial shooting has been shown to be the most cost effective method of control.
  • Ground shooting is generally not effective in reducing the pig population unless intense shooting is undertaken on a small, isolated and accessible population of pigs.
  • Dogs may be particularly useful to remove the few remaining pigs left after poisoning and trapping campaigns. Dogs are able to locate and flush pigs out of areas of thick cover. Dogs should not be used to hold or attack pigs.
  • Do not use dogs or shoot in areas before or during poisoning or trapping operations.

Fencing

  • Though an expensive option, fencing can successfully reduce pig damage. Research has indicated that the most successful pig-proof fences are also the most expensive.
  • The most effective pig-proof fences use fabricated sheep mesh held close to the ground by plain or barbed wire and supported on steel posts.
  • Electrifying a conventional fence greatly improves its effectiveness if used before pigs have established a path through the fence.
  • Pigs are known to charge and try to breach an electric fence. Unless the fence incorporates fabricated netting they often successfully breach the fence.
  • For crop protection or to avoid lamb predation, pig-proof fences need to be constructed before the pigs become a problem. Once pigs have adjusted to feeding in a particular paddock fencing may be ineffective.
  • Constant maintenance is required to ensure that any damage can be quickly repaired and the fence remains a barrier to pigs.
Declaration details
  • A declared Class 2 species under the Land Protection (Pest and Stock Route Management) Act 2002.
  • Introduction, feeding, keeping, releasing and supplying is prohibited without a permit issued by Biosecurity Queensland.
  • Landholders are required to control declared pests on their property.

Last updated 07 August 2014