Lethal Control of Marsupials
About Lethal Control
Species of Tasmanian wildlife that impact on human economic activities such as forestry and farming are ‘controlled’, in most cases, using lethal methods. These methods include the use of poisons, shooting and trapping. The species that are most commonly targeted are Bennetts Wallabies, Tasmanian Pademelons and Brushtail Possums (see Issues Sheets Nos. 6). Populations breed according to available food, so the killing cycle is virtually endless unless non-lethal methods are used. Repeated killing can have a long-term impact on the social and age structures of wildlife populations (see Bennetts Wallaby Species Sheet).
Use of the cruel poison 1080 is decreasing. In 2005 the Tasmanian Government phased out the use of 1080 by Forestry Tasmania, due largely to public disgust, and began research into alternatives. The private forestry industry has also ceased using 1080 but still has legal access to it. A small number of farmers still use a significant quantity of 1080 each year. Forest industries have largely switched to shooting instead. The government ‘Tasmania Together’ target is to phase out 1080 by 2015 – this will only be reached if widely accepted alternatives are found. Unfortunately, much of the research into alternatives centres on lethal methods of protecting crops and regenerating forests.
There have been trials into ‘best practice’ shooting, night vision goggles, trapping methods, and other types of poisons such as cyanide. There is also development of a commercial industry derived from shooting and trapping.
1080 and Other Poisons
Each year sufficient carrot bait impregnated with 1080 is laid in Tasmania to poison over 300,000 wallabies, pademelons and possums. The amount used varies from year to year and depends to an extent on weather conditions.
Death by 1080 is painful, prolonged and distressing. Animals stagger around, thirsting, frightened, disoriented and convulsing, sometimes for days until they succumb to central nervous system collapse, coronary or respiratory failure or are attacked by predators they cannot fend off due to paralysis. An RSPCA Report “Incidence of Cruelty to Wallabies in Commercial and Non-Commercial Operations in Tasmania” recommended 1080 use be banned for causing excessive cruelty.
Joeys of poisoned marsupials suffer horrendous deaths from starvation, exposure, or poison in their mother’s milk. The people responsible for clearing the carcases, working under time pressure, do not check pouches so joeys may be buried alive.
Many non-target species are also affected by the cruelty of 1080, in particular Bettongs and Potoroos. People who collect the dead animals for disposal also report picking up Ring-tail Possums, Wombats, Eastern Quolls, Shrike-Thrushes, Forest Ravens, Herons, Hawks and Owls.
Most placental mammals are much more susceptible to 1080 poison than marsupials. Poisoned marsupials can wander kilometres before they die, and remain lethal until they have decomposed entirely, so pets are at risk if there has been a 1080 drop within three kilometres. Many pet dogs die in agony every year through accidental secondary poisoning. Some symptoms of secondary poisoning in dogs are hyper-sensitivity to noise, copious drooling, running about yelping, barking madly, trying to hide, trembling and hyper-extension of the limbs.
Even where 1080 is used for conservation purposes against introduced animals on the mainland, its use is contentious due to excessive cruelty to its victims. Only in Tasmania is 1080 used routinely and indiscriminately to poison tens of thousands of birds and mammals who suffer a protracted and distressing death simply tomaximise profits for a small number of primary industries.
In the Tasmanian trials spillage from bait feeders, made worse by Forest Ravens that learned to access the feeders, made bait available to non-target species. More trials were recommended but none have taken place to date.
Cyanide kills more quickly than 1080, but no less violently. Unconsciousness for wallabies in trials has averaged 12 minutes, with some taking over 20 minutes to fall unconscious. During that time they suffer horrifically from muscle spasms, gasping for breath and convulsing. The issues with orphaned joeys are the same as for 1080.
Because of its fast action cyanide is considered, in a number of countries, too hazardous for pest control and its accessibility in the landscape presents a serious biohazard.
Each year around 1.4 million Pademelons and Wallabies, and about 300,000 Possums are shot under permit. Shooting is intrinsically cruel and even the best shooters with the best equipment will wound some animals that escape to die a very slow and painful death. In reality many shooters practice poor shooting methods, such as shooting out of range, causing much higher levels of wounding.
There is a 12 month permit ‘season’ for shooting Pademelons and Wallabies in Tasmania. Shooting using a spotlight and from a stationary vehicle is prohibited without a specific permit, though landowners can easily obtain such a permit. They may then issue that permit to licensed hunters. Shooters can also obtain a commercial license so that they can sell the meat and skins of their victims. There is no set limit on the number that can be killed in mainland Tasmania. Hunting wallabies using shotguns is banned in four mainland states for commercial shooters. This is because the guns are less accurate and injured animals can escape to suffer and die from injuries, infection or starvation. However shotguns are widely used in Tasmania.
Shooters use packs of dogs to flush animals out from the undergrowth. Tasmania is the only state in Australia where it is legal to use hunting dogs for this purpose. Although it is not legal to do so, dogs are also known to maul and kill the wildlife. Hunting dogs can cause extreme distress, severe injuries and death to Bennetts Wallabies and Tasmanian Pademelons and also other protected species: Quail, Native-hens and other ground dwelling birds; Bettongs, Potoroos, Eastern Quolls, Bandicoots and Wombats. The animals panic, bolting from their hiding places at great speed which can result in broken necks and limbs from collisions with fences and the involuntary ejection of pouch young due to stress.
Hunted animals may also suffer from capture myopathy even if they escape, a condition caused by exertion and muscular stress, which is sometimes fatal. The practice of shooting is not supervised and there are anecdotal reports of joeys being fed live to dogs or being left to die of exposure.
Spotlights and vehicle noises often scare animals away make them gun-shy. To address this problem, night vision and thermal scopes have been trialled in Tasmania and are starting to be used. These allow the shooter to literally see in the dark, and shooting is done from a stationary position. Using bait to lure animals, these scopes allow the shooter to shoot far more animals at once than ever before. Silencers are also being considered as an option.
The use of leghold traps is banned in Tasmania for control of native animals. There has been research as a part of the 1080 alternatives program into using capture or box traps, holding the animal in a cage. The animals are then killed.
Trapping puts a lot of stress on trapped animals, who are confined to the trap until collected and shot. Trapped animals exhibit “acute anxiety activity”, pacing backwards and forwards up to 100 times. That they then settle down, does not mean they are calm or in any way content, merely that they have resigned themselves to their captivity for the present time, in much the same way as the human animal reacts to being imprisoned.
Trials into trapping shows the futility and carnage caused by lethal control. Over the space of 16 months 379 possums were trapped at one site on 11 separate occasions. While the first month had the highest number captured (75), the second last had the second highest number (56). Animals will continually repopulate areas where the feeding is good. Adult animals move around in search of food, or in the case of possums, it is often young animals seeking their own territory.
Against Animal Cruelty Tasmania, Tasmanian Conservation Trust & Voiceless © 2012