Did you know that some “pests” are actually native animals, that are persecuted for trying to survive? Many of the others are the descendants of animals who were deliberately released or abandoned. Some were imported simply so Australia would seem more like “home” or so European colonists had a supply of familiar European animals they could hunt for fun. Others were shipped to our shores as sources of labour or were sent overseas with soldiers during wartime but were abandoned when cars and trucks became more widely available.
Today, they are killed in vast numbers using methods that would be illegal if done to any other species. From traps laced with deadly substances, baits injected with a poison our own government says is a chemical of national security concern, deadly gases pumped into their underground homes and viruses intended to eradicate them from existence, unwanted and unwelcome animals across Australia face a threat the scale and likes of which would easily outcompete every war humans have ever waged.
This blog explains the animals targeted, the methods used to kill them and the problems they cause – sometimes unexpectedly.
The story of Australia’s wildlife is steep in contradiction and myth . Despite a common belief that only introduced animals attract the death-sentence attached to being a “pest”, natives are not immune either .
The dingo is one of Australia’s most iconic animals. They are unique in the list of “pest” species because they were not introduced after European invasion. Though the first documented sighting of a dingo was recorded in the early 17th century, they have been present on the Australian continent for at least 5,000 years . Ever since European agricultural techniques were first introduced in Australia, governments have spent millions on “dingo control” programs .
Like dingoes, kangaroos are an Australia iconic, but this status does not prevent them from being controlled . The coordinated killing of kangaroos began “at exactly the same time” that kangaroos were first identified by invading colonists and shortly after, they were formally classified as a “pest” [6, 7].
The adorable, eucalyptus eating koala, is listed as “vulnerable to extinction” in parts of Australia, but this hasn’t stopped them from being considered a “pest” at times [8, 9]. During the approved culling, these animals are often euthanised . Interestingly enough, some areas have used sterilisation to reduce population numbers, something is is considered too expensive for other species .
The wombat was once widespread across south-eastern Queensland, New South Wales, and most of Victoria, but sadly, their populations have dwindled due to land clearing, road mortality, disease, and culling . Farmers consider them a pest, as they are known to damage fences. Thankfully, they are now protected in NSW and Victoria, but those residing in other states are not awarded the same compassion, labelling them as “pests” .
Possums are yet another species who is considered a “pest” depending on where they are found, as their diet and lifestyle is said to “damage plantations, hinder regeneration, fruit trees, and buildings” . For this reason, it is legal to have them removed and relocated. In some instances, it is legal to have a veterinarian euthanise them . In other cases, it is legal to kill possums for commercial use [16 PDF].
During European invasion, emus, like kangaroos, became a target. They were wiped out completely in Tasmania . Since then, they have been listed as a “protected” species, however, they can still legally be killed on private property with a license. This means that farmers can apply to kill emus that are found on their property .
Domestic rabbits first arrived in Australia with the European invasion of the First Fleet in 1788 . Their potential to cause damage was already known when 24 rabbits were released in Victoria to hunt for fun and “to help settlers feel more ‘at home’” [22, 23]. Soon, rabbits quickly spread at a rate of up to 10-15km a year . Hunters couldn’t keep up with them. By the late 1800s, they were described as having reached “plague proportions” . By the beginning of the 20th century, the Western Australian government erected a 1700 kilometre “rabbit-proof fence” . In a move that mirrored the ill-fated release of cane toads less than a century later, cats were once actively released to prey upon them [27, 28]. Today, they are branded as being “Australia’s most widespread and destructive environmental and agricultural feral pest” [29, 30].
Like rabbits, foxes were introduced to Australia to hunt for fun. They were imported by hunting clubs as early as 1835 so colonists could “emulate English fox-hunters” [31, 32]. Some of these groups still exist across the country . By 1845, a bounty had been placed on their heads . Today, foxes are found in most areas of Australia . The only exception is the island state of Tasmania [36, 37]. On the mainland, they continue to be targeted and killed in large numbers. They are hung from trees as strange “warnings” to others or as morbid kill-counts [38, 39]. In NSW foxes are declared “pests” and it is illegal to rescue, house, or provide veterinary care to foxes , doing so risks significant fines .
It is estimated that nearly 4 million cats currently live across Australia as domestic companion animals protected by laws and policies [42, 43]. These protections and any duty of care vanish when they become “feral”. Estimates place their number at between 2.1 and 6.3 million, though these figures vary dramatically and there is no consensus concerning the actual number . Official estimates have been “out by tens of millions” . Yet cats are the targets of one of the largest control programs in Australia. In 2017, the government announced a plan to kill 2 million cats, despite the overwhelming inconsistencies in their estimated population [46, 47].
Like many of the animals in this list, pigs were first imported to Australia as livestock by European colonists . Individuals soon escaped and established wild populations across the country [49, 50]. Today, governments estimate that there are up to 24 million wild pigs across approximately 40% of Australia . They can be found in NSW, Queensland, the Northern Territory, and the Australian Capital Territory . They are considered a “priority pest animal” in many states, including Victoria and NSW, where they are accused of causing a slew of agricultural, economic, and environmental impacts [53, 54]. In other states, such as Queensland, they are considered an “invasive” animal and all citizens are expected and legally required to participate in their control .
Our relationship with wild horses has been described as “curious” because unlike many other animals on this list, brumbies evoke the passion of many Australians , and activists and environmentalists often clash [57, 58]. Centuries after they were imported and set hoof on Australian soil, politicians continue to engage in a heated debate about the issue, the alleged impact they have on the environment, and the ethics of killing an animal many Australians regard as an iconic part of our national heritage [59, 60]. Some political parties promote the continuation of lethal control, while others have committed to banning certain techniques and an expansion into research on non-lethal methods . Some governments enforce a “zero-tolerance policy” on their presence . They continue to be routinely targeted and shot in the thousands by marksmen in helicopters .
Deer are native species in all continents except Antarctica and Australia . They were originally introduced here in the 19th century so settlers could hunt them for fun . In over 170 years, 22 species of deer have been imported to Australia, and only six of these are found in the wild today . They have a contested “semi-protected” status which many other declared “pest” species do not enjoy . This had led some to call them “the protected pest” . This protection, however, is limited . Recreational hunting has been the main method used in attempts to reduce the number of wild deer . They are considered to compete with farmed animals for resources and are blamed for causing damage to the ecosystem . Studies, however, have found that “perceptions of damage caused by deer are often overestimated or wildly exaggerated”. In fact, some of the damage deer are blamed for is actually caused by native Australian animals .
Donkeys were first introduced to Australia in significant numbers in 1866 when they were used as pack and draught animals . Despite being invaluable to early colonists, they were soon replaced by motor vehicles and abandoned in large numbers [74, 75]. Studies have found that the same qualities that made donkeys useful to humans allowed them to “flourish” when they were let loose . Donkeys are now found in north-western, western and central Australia . As they offer little to no value to humans, they are widely considered “pests”. For this, donkeys are one of “the most used, and abused, animals in history” .
Goats arrived in 1788 with the First Fleet . The wild populations that exist across the country today are the descendants of animals who were brought to Australia as “a convenient livestock animal” but escaped captivity . Most were farmed for their meat and milk . Others, such as those brought to South Australia in 1837, were intended to provide fibre . Soon, Angora and Cashmere were imported to start a commercial goat fibre industry . Today, wild goats are found in all states and territories with the exception of the Northern Territory . They are considered to be “pests” because they can impact agriculture and the environment . Like donkeys, wild goat populations have thrived in areas where habitats have been modified for farmed animals . Unlike donkeys, however, they have commercial value and are taken from the wild to be killed and sold as meat .
Even though they are not native, Australia is home to the largest herd of camels in the world . They were originally imported during the 19th century and were used for transport and labour . Like the donkey, the invention and development of motor vehicles meant camels were no longer needed . Thousands were deliberately released into the wild . In 2008, estimates placed the number of wild camels at one million . A year later, $19 million in management funds were allocated to controlling their population . Wild camels are caught and used for entertainment purposes, such as camel racing, rides for tourism, and for the production of milk and meat [94, 95].
A range of techniques have been developed to limit or control the alleged impacts caused by these animals. The majority of these methods of lethal. Many of them cause significant suffering – even those that may not appear lethal often present deadly threats to a range of species. Many control programs do not conduct population assessments before or after killing. This limits the ability to provide reliable data on the true effectiveness of lethal control. For example, a Parks Victoria employee explained that “we don’t have a particular target [because] with pest animals it’s not about targets, it’s just about reducing as many as you possibly can” . This attitude translates into a blind reliance on death as the only method of population control and ignores any of the other impacts operations may have.
Fences, barriers and boundaries
Until the gold rushes coaxed them elsewhere, many early colonial Australian farmers tended to their flocks as traditional shepherds . When the scale of their operations made this impossible, fences were erected and used in their absence . When farmers realised that new technologies diminished the need for their on-site labour, flocks were “left to fend for themselves”, often in large open paddocks .
Originally erected in the 1880s as Australia’s famous “rabbit-proof fence”, today the “Dog Fence” is the largest barrier fence found anywhere in the world [100, 101]. It is primarily used to protect sheep from dingoes .
There has been a range of unintended consequences tied to the use of barrier or exclusion fencing . Each kilometre of the “Dog Fence”, including the roads that run alongside it, occupies an environmental “footprint” of around 2 hectares . RSPCA Australia explains that though there may be some benefits to fencing, including a decrease in predation, “there are also animal welfare impacts on animals on the outside of the fence”, including injury, distress and death caused by starvation, thirst or exposure. They can also “halt natural wildlife movement patterns” and impact biodiversity by reducing the possibility of animals separated by the fence from interacting . Studies have also found that the barrier “has altered the ecosystems of Australia’s outback” and caused significant ecological ripple-effects [106, 107]. The removal of predators, particularly apex predators like the dingo, can lead to rapid increases in herbivores . This dramatically impacts the environment, mostly vegetation and soil quality [109, 110].
Poisoning and viruses
In Australia, poisons are used to kill animals considered to be a threat to agriculture . According to one contemporary account, “humans are using toxic compounds in a useful fashion to control their environment to their benefit” . Do these alleged benefits outweigh the impact they have on the animals and do they really do what we are told they do?
Sodium fluoroacetate, commonly referred to as compound 1080 or simply ‘ten-eighty’, is “one of the most toxic substances” known to exist anywhere in the world . It is so noxious that there is no known antidote [114, 115].
Assessments of 1080 have concluded that it causes “severe suffering” . A study published by an RSPCA Australia scientist in the journal Animal Welfare concluded that 1080 “should not be considered a humane poison” . According to the RSPCA, the symptoms of 1080 poisoning include anxiety, frenzied behaviour, hypersensitivity, failure to respond, retching, vomiting, screaming, shaking, uncontrolled urinating or defecating, convulsions, fits, seizures, difficulty breathing, coma and death . Aside from these welfare issues caused by the symptoms of 1080 poisoning, victims may injure themselves during periods of lucidity . For welfare reasons, veterinarian advice is immediate euthanasia because there is nothing that can be done to save the victim once it is ingested [120, 121]. As it is lethal to all air-breathing animals, it poses a threat to any animal unlucky enough to “take the bait” – including companion animals and native species [122, 123, 124]. It also poses a secondary threat to animals who scavenge the bodies of poisoned animals or those who ingest poisoned vomit .
Due to growing public concern about the use of 1080, new poisons have been developed – one of these is PAPP (para-amino-propiophenone). PAPP was originally investigated as a potential antidote for humans poisoned with cyanide . In 2016, it was developed to kill dingoes and foxes  and has since been used to kill cats . It reduces the amount of oxygen in the blood by disrupting the level of haemoglobin and causes unconsciousness and death by lack of oxygen supply to the brain and the heart .
Animals poisoned with PAPP collapse and are eventually incapacitated – it is what they endure before they die that is significantly concerning. The time between ingestion and the onset of symptoms can be anywhere between 43 minutes and 15 hours . The symptoms a victim experiences include nausea, vomiting, incoordination, tremors, elevated respiratory and heart rates and haemorrhages from orifices . The time between collapse and insensibility can be anywhere between 30 minutes and 8 hours . During this time, they face a range of potential welfare impacts, including predation from crows, dogs, foxes or other predators, injury, exposure and distress .
Strychnine is “very toxic to mammals, birds, and aquatic organisms” . It is used to kill declared “pest” species or inconvenient animals across Australia. Like 1080, there is no known antidote to strychnine poisoning . It functions by locking onto receptors which control the muscles. When one muscle contracts, the corresponding muscle should relax. Strychnine blocks this transmission and causes both to “contract violently” . These muscles include those responsible for respiration, preventing the victim from breathing . Ultimately, death is caused by suffocation or “sheer exhaustion” [138, 139]. In some states, strychnine is used by applying it to a cloth which is then attached to the jaws of traps to kill dingoes (“wild dogs”). It is then ingested by dingoes as they attempt to free themselves of traps . It is also laced in grain baits to kill wild emus .
Similar conclusions have been reached about the use of 1080 and strychnine . It causes “excruciatingly painful spasms” and “violent convulsions” because it interferes with their proper functioning . Studies have concluded that it can take up to 24 hours or longer for a victim to die and “death by strychnine ingestion is inhumane” . The World Organisation for Animal Health (OIE) considers strychnine poisoning to be “unacceptable on animal welfare grounds” .
Pindone is an anticoagulant used to kill rabbits . It is applied to cereals, oats or carrot baits; the most common baits are carrots and oats [147, 148]. Baits are laid in small piles in areas with known rabbit populations and are replaced every two days until the amount eaten each time drops .
Studies have concluded that pindone poses welfare impacts greater than other poisons currently used to kill rabbits . This conclusion has led reviews to conclude that pindone poisoning causes extreme suffering . Symptoms of pindone poisoning include difficulty moving and breathing, coughing, bruising, bleeding from various bodily orifices, including the nose, mouth, eyes and anus [152, 153, 154]. Symptoms usually appear six days after a bait is eaten, though it can take up to 14 . Rabbits who ingest a sub-lethal dose of pindone may recover, but they experience anaemia, lameness, bruising and bleeding in vital organs, such as the lungs .
There is no reliable information about how pindone breaks down in poisoned animals and it may pose a secondary threat to scavengers who consume their carcasses . Pindone is an anticoagulant, which interferes with the ability of the body to clot blood, a range of other animals are at risk during a baiting program [158, 159]. During the initial baiting period, these include animals who may take the baits themselves. Others can be killed if they scavenge the carcass of an animal poisoned during the first baiting phase .
Gassing, warren ripping and explosives
Unlike other techniques which are used to kill a wide range of species, gassing, warren ripping, and explosives are usually reserved for rabbits. Occasionally den fumigation and ripping is used to kill foxes . Gassing is described as “the most effective method of reducing rabbit numbers where burrows are accessible” . During the 1960s, exhaust fumes from cars were fed into rabbit warrens . This technique, referred to as “fumigation”, is used to kill rabbits across Australia today using different techniques . Modern techniques use carbon monoxide or phosphine gas which disrupt the central nervous system and respiratory function . “Ripping” refers to using heavy machinery, such as tractors, to destroy the underground homes (dens) of rabbits or foxes . Sometimes warrens or dens are destroyed using explosives .
Gassing using various fumes causes significant suffering . Blasting with explosives is considered “more humane” if it causes complete collapse even though there have been no studies “formally assess the effectiveness or humaneness” of the method [169, 170]. If the explosives are not placed in a position which causes complete collapse, some rabbits can become trapped in partially destroyed tunnels and suffocate or die from “blast-related injuries that were not immediately lethal” .
Hunting / Shooting
There are three main groups of animals hunted in NSW. These are introduced game species, native birds and introduced “pest” or “feral” animals. Hunters use a range of weapons, including firearms, bows and knives . In most states, it is legal to hunt some species with dogs (“pig dogging”) . Across the country, many millions of animals are killed in government and private control programs each year.
There are two main types of shooting practiced across Australia: ground and aerial. Ground shooting is widely used across the country to kill a range of species, including donkeys, camels, goats, horses, pigs, foxes, birds, rabbits, deer and dingoes [174, 175]. It is carried out by official government control officers, landholders and professional or licenced shooters across the country . Aerial shooting involves the use of firearms from helicopters. It is most often used to kill horses, donkeys, goats, camels, and pigs after other methods, such as trapping and mustering, have been applied .
Recreational hunting is killing animals for “sport” or enjoyment. This is usually done by firearm, arrow, or knife . Bowhunting is legal in NSW and Victoria [179, 180]. Knives are usually used to kill animals who are already incapacitated, such as pigs taken down by dogs in “pig-dogging” . Recreational hunting is usually justified by claims that it removes unwanted wildlife, including “pest” animals from the environment and aids or enhances other conservation efforts [182, 183, 184, 185]. Studies have found “insufficient evidence to support or disprove arguments that contemporary recreational hunting programs are effective at controlling introduced mammal populations” and that current programs “offer little” to prove its value as a control tool .
Shots to the “kill zone” (i.e., vital areas which cause immediate death) are often considered humane as they result in rapid unconsciousness and death [187, 188]. The area is not the same for every animal [189, 190, 191]. The size of the target required to effectively and immediately kill most animals is “not much larger in size” than a small apple . There are many difficulties associated with ensuring that an accurate shot is made . Under most policies, wounded animals must be quickly located and killed . Some animals, however, can travel for a long distance after being shot before finally dying .
Hunting with dogs
“Pig dogging” is a form of hunting which uses dogs to assist in finding, pursuing and restraining wild pigs . It is legal in NSW, though there are some conditions in other states [197, 198]. Though it is a controversial method, it is described as “a popular recreational and commercial activity” by the NSW Department of Primary Industries (DPI) . Piglets have been videoed being released by hunters in an effort to ensure their presence for upcoming hunting expeditions . Despite being illegal, this practice directly contradicts claims repeatedly made by hunters that their killing is an act of conservation .
Under NSW law a person must not “cause, procure, permit, encourage or incite a fight in which one or more animals are pitted against another animal or animals” . Despite this, pig dogging remains legal. Dogs used when hunting pigs can suffer “severe injuries” . Sometimes the wounds they sustain when attempting to take the pigs down are fatal. Other injuries are treated by the hunters instead of providing them with proper veterinary care . Some studies have found that dogs intended as “pig-dogs” are bred “surplus to requirements” in a manner similar to overbreeding in other entertainment industries, such as greyhound racing . Like greyhounds, dogs not considered suitable because their nature is incompatible with killing pigs are killed as “wastage” . If they are suitable and they are used to kill pigs, they can be branded as a threat or a “future danger to the public or [other] animals” and be killed (“euthanased”) .
Hunt clubs and “fox drives”
Though hunting foxes with dogs on horseback was outlawed in Scotland in 2002 and banned in England and Wales in 2004, it is still legal in some parts of Australia [208, 209, 210, 211, 212]. Though rare and dwindling in numbers, some groups which practice “fox drives” have existed in Australia for over 160 years [213, 214, 215]. These groups “flush out” foxes who are then followed by a pack of hunters, sometimes on horseback . These are known as “fox drives”. The foxes can be chased by dogs or a second group of hunters who “drive” them to hunters armed with firearms, usually shotguns . When using people to scare foxes from their hiding spots, one group of hunters assemble in a line approximately 50 metres apart. Another group, known as “beaters”, are positioned in a strategic area so that when the foxes attempt to escape they “drive” them towards the armed hunters .
According to the Australian RSPCA, recreational hunting causes “inevitable pain and suffering” and it “is not an effective form of pest management” . Their policy states that “recreational hunting or the act of stalking or pursuing an animal and then killing it for sport cannot be justified” despite any “skills, knowledge or motivation” the hunter may have . Our recent blog on kangaroos showed that non-commercial or recreational hunting leads to far more cruelty and a far higher degree of inhumane killing due to the lack of regulation and competency testing required. The same may be said of the hunting of introduced or “pest” animal species. In some states, such as NSW, you do not need to hold such a licence if you intend to kill “feral” or “pest” animals. These animals include foxes, as well as rabbits, deer, goats, rabbits, cats and “wild dogs” (dingoes) .
There are no statistics on the number of animals trapped in Australia each year. Usually, an animal is trapped and then shot in the head with a rifle or other firearm . The traps most commonly used are cage or leg- and foot-hold traps. Cage traps use wire mesh and come in a variety of sizes depending on the animal intended for trapping . They have a spring door which is triggered by a plate or hook mechanism which shuts the entry once an animal sets foot inside . They can be disguised with sticks, leaves or other organic materials found nearby the site and are usually left outdoors so that they smell “natural” . Most policies dictate that traps must be regularly checked though it is rarely if ever governed or enforced . Because they may be set in areas in remote or rural Australia, this is considered an impossibility by the RSPCA .
Trapping results in severe physical and psychological suffering . Leg-hold traps can cause severe injury to target or non-target animals, including swelling, lacerations, and dislocations . Animals often inflict injuries on their feet and legs attempting to escape and cause damage to their teeth, lips and gums from chewing on the jaws of the trap [220, 221]. The victim can also be vulnerable to predation by other animals or succumb to exposure if left without food, water or shelter .
Bounty programs promote the killing of unwanted animals and offer cash rewards when evidence is presented as proof. Some local Councils still offer up to $25 per dingo or fox scalp [223, 224]. Some have started offering bounties for cat scalps . The reward ranges from up to $40 to $120 for a dingo or fox scalp and as little as $10 for a cat scalp [226, 227, 228]. Between 2011 and 2017, over half a million fox scalps like those in the photo below were collected in Victoria . In less than six months, over 60,000 fox scalps can be collected by the Victorian government .
Bounty hunters often use “inhumane and non-selective killing methods” which cause animals significant suffering and protracted deaths . Often, the bounty systems have little effect [232, 233, 234]. Australian studies have found that a bounty across Victoria “was not considered to cause a useful or lasting reduction in fox numbers” despite over 200,000 foxes being killed . There have been examples where bounties played a role in extinctions, however. For example, the extinction of the Tasmanian tiger was “caused in larger part by farmers and bounty hunters” . RSPCA Australia maintains that “bounty schemes should be discouraged” . International studies have found that they actually “compromise wildlife conservation efforts” .
For some time it has been widely acknowledged that over-reliance or dependency on one control technique or strategy, such as poison baiting using 1080, is “unwise” . There is a growing push for the development of humane alternatives [240, 241]. Experts ask why we continue to invest billions of dollars in the same techniques we have used for decades “when a more proactive and natural alternative exists” . That alternative depends on a range of factors. For some, the solution is nature itself. They argue that “the dingo is in fact a sorely under-utilised weapon in our feral-animal arsenal” . They cite the lower levels of other animals, particularly smaller introduced predators like foxes and cats, in areas where dingoes are abundant [244, 245]. In other situations, we can implement Trap-Neuter-Release, or sterilisation programs . According to Tatiana Samoylova, an associate research professor in Auburn’s College of Veterinary Medicine, “current control programs that focus on wild pig eradication via trapping and shooting are expensive and ineffective. Contraceptive vaccines can, over time, significantly reduce populations to manageable numbers and are more acceptable means of population control to the general public” .
Animal Liberation’s Stance
Animal Liberation promotes the adoption of the 7 principles of ethical wildlife management. These principles were developed in response to opposition to current control techniques and the fact that “commonly used control actions are inhumane, ineffective or not based on scientific evidence” .
What can you do?
After over 60 years of deadly and indiscriminate control, it is clear that killing isn’t working. Until we learn to coexist with wild animals, many more will continue to die painful, avoidable and shocking deaths by bullets, baits or any combination of the methods outlined in this blog.
While there isn’t a lot you can do, you can help us fight for these issues by being vocal, sharing content about their plight, and supporting organisations like Animal Liberation so we can continue to be a voice for these animals in parliament and lobby for change.