Review of the management of feral animals and their impact on ...

effort on <strong>the</strong> control <strong>of</strong> <strong>feral</strong> pigs, however <strong>the</strong>y are having a problem from not
dealing effectively with immigration, <strong>and</strong> thus <strong>the</strong> control efforts are typically
not effective in <strong>the</strong> long-term. Feral pigs are controlled in National Parks <strong>and</strong>
Conservation Reserves with integrated programs using some or all <strong>of</strong> aerial <strong>and</strong>
ground shooting, poisoning (1080, warfarin), <strong>and</strong> trapping. Aerial shooting is
<strong>of</strong>ten much more effective than shooting from <strong>the</strong> ground, provided that it is
used frequently enough <strong>and</strong> on a scale sufficient to prevent immigration or
recovery through breeding. Trapping can be effective but results are variable. It
is used most <strong>of</strong>ten as a follow up after an initial knockdown <strong>of</strong> a population, or
when poisoning is impractical or in conjunction with poisoning. Ground
shooting <strong>and</strong> dogging are not used by NPWS due to ineffectiveness, although in
some jurisdictions <strong>the</strong>y are used opportunistically to follow up after initial knock
down has occurred.
NT – Limited control is undertaken in conservation reserves <strong>and</strong> National Parks using
1080 ground baiting. The Judas pig technique has been used to eradicate small
isolated <strong>feral</strong> pig populations in <strong>the</strong> past (McIllroy & Gifford 1997). Off-reserve,
<strong>the</strong>re are no formalised control programs <strong>and</strong> many l<strong>and</strong>holders invest little in
control o<strong>the</strong>r than opportunistic shooting <strong>and</strong> sport hunting. Some baiting <strong>of</strong>
carcasses with CSSP in cropping areas is also undertaken by l<strong>and</strong> managers.
QLD - The control methods used for <strong>feral</strong> pigs are strongly determined by <strong>the</strong> market
price for <strong>feral</strong> pig meat. When prices are high, hunting, harvesting <strong>and</strong> trapping
for commercial sale are <strong>the</strong> predominant techniques used. In 2001,
approximately 240 000 <strong>feral</strong> pig carcasses were processed. This is supported by
extensive 1080 ground baiting. Queensl<strong>and</strong> is also <strong>the</strong> only state in Australia
where it is legal to aerially bait for pigs <strong>and</strong> proves to be an effective measure
for broad-scale control. The non-target <strong>impact</strong>s are still somewhat unclear.
When market prices are low, efforts are increased in baiting <strong>and</strong> hunting.
SA - Feral pigs are not overly abundant in <strong>the</strong> Rangel<strong>and</strong>s <strong>of</strong> SA, occurring mainly in
<strong>the</strong> far north <strong>of</strong> <strong>the</strong> state. The majority <strong>of</strong> control undertaken is via aerial
shooting in order to cover <strong>the</strong> vast <strong>and</strong> remote l<strong>and</strong>scape.
WA – Ground baiting with 1080 laced grain is <strong>the</strong> most common form <strong>of</strong> <strong>feral</strong> pig
control used in WA. Trapping is also frequently used, <strong>and</strong> has been <strong>the</strong> primary
control method in several cooperative control projects (Higgs 2002). Aerial
shooting is used in more remote areas with sparse vegetation <strong>and</strong> in <strong>the</strong> northwest
<strong>of</strong> <strong>the</strong> state <strong>and</strong> Fitzroy river regions, recreational hunters have worked
with l<strong>and</strong> managers to reduce local <strong>feral</strong> pig numbers though annual shooting.
Management <strong>of</strong> <strong>feral</strong> pigs in <strong>the</strong> Rangel<strong>and</strong>s
Like o<strong>the</strong>r <strong>feral</strong> <strong>animals</strong> that have a market value, <strong>the</strong> level <strong>of</strong> <strong>feral</strong> pig control varies
with community attitudes <strong>and</strong> market prices. The most effective <strong>management</strong>
techniques for <strong>the</strong> Rangel<strong>and</strong>s are aerial shooting <strong>and</strong> aerial baiting. These techniques
allow cost effective control <strong>of</strong> <strong>feral</strong> pigs over <strong>the</strong> vast <strong>and</strong> remote l<strong>and</strong>scape. In more
urban regions, trapping can be a useful additional control tool that also allows for
some control-cost <strong>of</strong>f-setting. Control efforts should seek to maximise <strong>the</strong> benefit
from environmental conditions as much as possible. Control will be easier <strong>and</strong> more
effective during times <strong>of</strong> drought when <strong>feral</strong> pigs are forced to congregate around a
small number <strong>of</strong> water sources <strong>and</strong> when food is scarce. Conversely, baiting
campaigns following rain may be ineffective due to <strong>the</strong> new-growth (‘green stick’)
available to <strong>the</strong> pigs, <strong>and</strong> shooting may be more effective.
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