be assessed by establishing the
effectiveness , cost effectiveness, safety to non-targets and practicality of the method.
- When feral pig control is planned, managers need to know how much control (effort per
unit area which varies depending on the efficiency of the method utilised and feral pig
density) to apply to achieve the required level of damage mitigation. In an ideal world, a
manager would have calibrated the relationships between control effort or cost and the
change in pig densities this would achieve and the resulting changes in the condition or
numbers of the valued resources being impacted by the pigs. However, this information is
rarely available a priori for managers, who are left with the difficult decision on how
much to spend to monitor their success or failure. If they spend too much of their budget
to achieve certainty, they restrict their ability to do more pig control. But, if they spend
nothing or too little on monitoring they run the risk that they did not achieve the goals of
the operation, the impacts remain unacceptable but they are unaware of this. The approach
to gain certainty depends on the scale and context of the pig control program, but
inadequately designed monitoring is usually money wasted. For most ‘conservation’ programs run by government agencies that cover many control operations about 15% of
the total budget appears to be the appropriate proportion to invest in monitoring. Whether
all sites need the same level of monitoring depends on how confidently managers can
extrapolate between sites and the quality of monitoring at priority or representative sites.
Research to understand the relationships between control effort/cost, pig densities and
impacts should be supplemented by planned adaptive management experiments using
differences in control operations to identify better management. When eradication is the
aim the only critical measure of success is the absence of pigs.
- Aerial shooting, ground baiting (warfarin and 1080), trapping and aerial baiting are all
highly effective control tools where appropriately used in suitable habitats.
- Other control tools such as fencing and the Judas pig technique can be effective but can
also be expensive and have high logistical requirements. Habitat modification and the
effects of hunting and harvesting on conservation values have not been researched to any
extent in Australia. Aerial baiting with single-dose meat baits may have high non-target
impacts in some circumstances.
- The humaneness of a control tool is an important consideration to avoid suffering of feral
- Many of the currently available, yet effective feral pig control tools, may potentially
impact on feral pig welfare in some way (minor to marked). However, the management of
feral pigs is an imperative due to the level of feral pig impacts on the welfare of other
animals and humans, and on the sustainability of natural resources. Therefore it is the
responsibility of land managers to minimise the suffering of feral pigs by utilising the
most humane yet effective control tool in a given situation. Support of research into new
tools which are demonstrably more humane and effective than some established methods
should also be encouraged.
- The assessment of the humaneness of a control tool can be assessed with the five step
humaneness review framework developed by Littin & O’Connor (2002) to assess the
humaneness of vertebrate pest control toxins in New Zealand. However, the data
necessary to definitively assess the humaneness of most control tools is incomplete, and in
most cases, data available are primarily concerned with efficacy.
- The available evidence suggests that warfarin, yellow phosphorus and hunting with dogs
may impact on feral pig welfare in a moderate or marked manner. However, the evidence
is incomplete. It is recommended that warfarin and yellow phosphorus be phased out of
use over the short to medium term.
- The available evidence suggests that 1080 and the Judas pig technique may produce minor
welfare compromises in feral pigs. However, the evidence is incom