Rabbits
Wild rabbits in Australia
Wild Rabbits are deemed under the Australian law to be pests (vertebrae pests). They are mainly killed by methods that would be considered inhumane and illegal under anti-cruelty laws if they were applied to companion animals.
It is lawful in Australia for rabbits to be poisoned, infected with disease, hunted, or caught in steel-jawed traps. Species deemed as 'pests' may be excluded from the operation of the anti-cruelty acts and be regulated through a Code of Practice, or their harm may be authorised by another piece of legislation. The most common rabbit control options aim to eliminate rabbits using poisons, fumigants or other specialised methods such as warren ripping, shooting or trapping.
The following are the control agents used against rabbits which also affect companion animals:
Biocontrol agents
Myxematosis
In 1950 the CSIRO released the myxoma virus. Myxoma is a disease that is known among vets to cause immense suffering to the animal. Affected rabbits can take a fortnight to die and treatment is futile, which is why euthanasia is usually recommended.
Classic myxomatosis symptoms start with runny eyes. The genitals are also usually swollen. It quickly progresses to become severe conjunctivitis which causes blindness, along with lumpy swellings on the head and on the body. The eyes become swollen shut due to excessive amounts of thick pus discharge.
If an unvaccinated pet rabbit catches myxomatosis, it will almost certainly die. Vaccination is a vital part of protective measures which are urged to be taken by vets outside Australia. Although myxoma vaccines exist in the UK and Europe, they are not allowed in Australia.
Calicivirus
In 1996 the Rabbit Haemorrhagic Disease Virus (RHDV1), a calicivirus, was brought to Australia as a rabbit biocontrol agent.
The disease infects many organs including the lungs, gut and liver of the rabbit. This in turn causes acute liver damage which can kill the rabbit within 48-72 hours. There is currently one vaccine released in Australia used on domesticated pet rabbits, known commercially as Cylap HVD. This vaccine however is not 100% effective and does not protect against the RHDV2 strain of the rabbit calicivirus which was discovered in Canberra in 2015, and later confirmed in Victoria and NSW.
A new Korean strain of calicivirus, K5 virus, has been released in Autumn 2017. Cylap HVD vaccine is recommended for pet rabbits. However, as with the RHDV1, it is not guaranteed to protect the rabbits from infection or death.
Poisons
Rabbits who ingest Pindone show signs of lethargy, depression followed by anorexia, anaemia, and bleeding. Bleeding around the nose, mouth, eyes and anus with bloody faeces are common symptoms. Pain and discomfort set in due to bleeding of the internal organs. These symptoms last 10-14 days before death. Pindone restricts the routine synthesis of vitamin K-dependent blood clotting factors in the liver which damages the normal daily function and repair to blood vessels.
Common signs of 1080 poisoning in rabbits include lethargy, laboured respiration and increased sensitivity to noise and disturbance. Convulsions occur accompanied by gasping and squealing. Death follows 3-4 hours later.
1080 is toxic to a wide range of species including birds, mammals and reptiles. The poisoning of non-target species can occur either directly by eating baits intended for rabbits (primary poisoning) or through the scavenging of tissues from a poisoned animal (secondary poisoning).
Warren destruction: 'ripping,' explosives, fumigation
In many areas of Australia, rabbits depend on warrens for shelter from climatic extremes, predator avoidance and also for successful breeding. Warrens are destroyed using ripping or, in rocky or inaccessible areas, explosives. Rabbit warrens will also be 'fumigated' with toxic gases. Since rabbits do not readily dig new warrens, rabbit populations do not persist in areas where warrens are effectively destroyed and re-colonisation is made less likely. These methods also lead to the death or severe injury to rabbits who are in the warren at the time.
Warrens are destroyed using a tractor or bulldozer fitted with single or multiple-tined rippers.
Blasting is used to destroy warrens in areas that are inaccessible to ripping (e.g. rocky areas, under trees, along rivers and in steep sandbanks) and in areas where ripping is undesirable because of the risk of soil erosion. Correct blasting does not leave any craters, but lifts the subsoil and drops it back into place compressing the warren system in the process.
Fumigation involves the introduction of toxic fumes into a warren where it is inhaled by rabbits leading to their death. There are two types of fumigation: pressure fumigation, in which the fumigant gases or vapours are generated outside the warren and forced into the warren under pressure, usually from a pump and; diffusion fumigation, where tablets are placed in active burrows and the gas generated is allowed to diffuse through the warren.
Other methods
Rabbits are also frequently shot by hunters and farmers and can be legally caught in leghold traps on private land.
