Trapping is one of the most common techniques used to control feral pigs in Australia. In the Wet Tropics of Queensland, where non-target native species are abundant, trapping is regarded as the safest and most appropriate method. However, it can be labour intensive and is not practical for a large scale control in grazing areas due to the substantial costs associated with obtaining equipment (building or purchasing traps) and carrying out regular maintenance. It is also difficult to achieve a rapid reduction in pig populations using trapping. Nonetheless, it is a useful technique for areas where poison baiting or shooting is not feasible, such as near towns. Trapping can also be used to manage pigs at relatively low densities or to protect areas for high-value crops.
“Trapping success depends on several key components such as timing, location, bait material and free feeding”
Panel, silo and box traps are the different types of traps currently available. A panel trap is a series of weldmesh panels wired together and supported with steel posts at the corners and panel centres. The size and shape of the panel trap can be changed by removing or adding panels so that rocks and stumps are avoided. Panel traps are relatively easy to construct, dismantle and transport.
A silo trap is built from a continuous mesh and is stronger than the panel trap while being flexible enough to prevent pigs from climbing out or breaking the mesh.
Silo traps are more suitable for semi-permanent trap sites because they are more difficult to construct, dismantle and transport than the other designs.
A box trap is portable and designed to fit onto the back of a standard 4WD tray back. It is particularly useful on smaller properties. The easy relocation of box traps makes them ideal for feral pig control, as seasonal movement of pigs caused by changing food availability means that traps often need to be moved to where the pigs are. Steel posts used at the corners of the box trap also prevent pigs from lifting the trap. Refer to Feral pig control2 for more details about these different trap designs.
Trapping is a process, not an event. Trapping success depends on several key components such as timing, location, bait material and free feeding. Trapping is most successful when alternative food resources are limited. An ideal trapping site is in the vicinity of recent pig activity, which tends to be in shaded areas of thick cover close to a water source. Trap sites should also be accessible by vehicle so pest controllers can carry large amounts of bait to the trap.
To maximise the probability of pigs encountering traps, sufficient numbers of traps need to be distributed in a given area. Mitchell recommends that traps be set out in a circuit to make daily checking easy2.
Grain (wheat, oats or barley with molasses or Carasweet® added) is often used as bait material. To improve bait attractiveness to pigs, grain may be soaked in water for at least 3-5 days to ferment. This will produce a strong odour and pigs will be more likely to find the bait. In some jurisdictions (eg Qld), it is illegal to directly feed animal meat or meat by- products to feral pigs. Operators will need to use a large amount of bait each time the trap is set (around 10-20 kg), so it is best to use materials that are readily available at little or no cost (eg discarded bananas in North Queensland).
The success of trapping also depends on free-feeding before setting a trap. The goal of free feeding is to accustom pigs to the new food source and attract them to the trap site, and importantly, to get all of the pigs in a group conditioned to entering and leaving the trap unharmed. Some pigs are trap-shy, especially older pigs and pigs that have been previously trapped and released. Usually one to two weeks of free feeding is necessary before the entire group will enter the trap.
Once bait is continually being taken from a site, trap materials should be left for 2-3 days so that pigs become familiar with the smell of the steel mesh. The trap can then be partially erected with the gate open and poisoned bait placed inside the trap. If pigs hesitate to enter the trap at first, some bait material should be placed outside the door or laid in a trail leading to the trap. Aromatic attractants such as vanilla essence, aniseed and creosote or sump oil, can also be added to bait materials. A few different bait types such as bananas, mangoes, pumpkins or rockmelons, can also be used if readily available.
Traps can also be incorporated into existing fence lines to funnel pigs toward the traps. The use of dogs will be counterproductive while trapping because they push pigs away from traps. Human activity at the trap sites should also be kept to a minimum. Ideally, remote cameras should be used to ensure the entire mob is readily feeding from the trap before it is set.
Once traps are set, animal welfare considerations need to be addressed. It is important to inspect them daily to release non-target animals as quickly as possible if they are trapped. Trapped pigs should also be removed as quickly and humanely as possible to prevent dehydration and heat/cold stress. Captured pigs need to be approached in a calm and quiet manner to prevent their unnecessary agitation, panic, stress and risk of injury. When shooting captured pigs inside the trap, only head shots are acceptable. The pig needs to be shot when it is motionless – never shoot when the head is moving. Smaller calibre rifles (eg .22 magnum rimfire with hollow/soft point ammunition) are recommended for euthanasia of pigs at short range (<5 m). For large pigs over 40 kg, 12 gauge shotguns may be used with shot sizes of SG or SSG. BB cartridges are suitable for small pigs less than 40 kg. The range should be as short as possible to maximise the impact of the shot and minimise the risk of misdirection. Shooting should only be performed by skilled operators with experience using firearms, and who hold the appropriate licences and accreditation. Firearms users must also comply with relevant legislation requirements for storage and transportation of firearms and ammunition.
Mitchell J (2011). Feral pig control. NQ Dry Tropics, Townsville, Queensland.
Sharp T (2012). Standard Operating Procedure (PIG001): Trapping of feral pigs. Invasive Animals Cooperative Re- search Centre, Canberra.
Invasive Animals Ltd has taken care to validate the accuracy of the information at the date of publication [January 2014]. This information has been prepared with care but it is provided “as is”, without warranty of any kind, to the extent permitted by law.
|Author||Centre for Invasive Species Solutions|
|Publisher||Centre for Invasive Species Solutions|
|ISBN/ISSN||PestSmart code: FPFS5|
|Region||Australia - national|
|Documents||FPFS5: Trapping for feral pig control in Australia [640kb PDF]|
|Links||PestSmart Toolkit for Feral Pigs: www.pestsmart.org.au/pest-animal-species/feral-pig/|