Fumigation for rabbit control is the introduction of poisonous gas into a warren. It is one of the best control methods to use where low numbers of rabbits live in a few widely scattered warrens. The threat to non-target animals is minimal. This article gives instructions for fumigation. It should be read in conjunction with registered product labels and directions for use.
When to use fumigation
Fumigation can be used effectively:
- as a follow-up technique to poisoning and warren ripping
- for spot treatment of small, isolated rabbit infestations
- where ripping is undesirable, because of the risk of soil erosion or damage to conservation areas
- where the poisons 1080 (sodium fluoroacetate) and pindone cannot be used because of the risk to non-target species, or where poison baits are unwanted
- when the rabbit distribution has declined under temporary harsh climatic conditions and rabbits are surviving in a few isolated pockets.
Fumigation may sometimes be used in areas where access is limited, such as fence lines, around trees and on river banks but it may be difficult to find and seal all the warren entrances in these situations.
Fumigation can be carried out at any time of year but it has the best long-term effect if done shortly before the start of the rabbit breeding season. Fumigation is not suitable when most of the rabbits are living above-ground rather than in warrens. This is likely in areas of scrub where there is a dense understorey, especially in coastal districts.
Static fumigation is done by placing fumigant tablets down each warren entrance. The main fumigant used is phosphine, which is released from aluminium phosphide tablets by reaction with moisture.
Chloropicrin was previously used but its use has been discontinued due to environmental and human safety concerns, and it is considered to be highly inhumane.
For phosphine fumigation to work effectively, the gas must build up quickly to lethal concentration throughout the warren. This will not happen if the gas is released from the tablet slowly - under these circumstances rabbits may have time to dig their way out. The speed of release of phosphine depends on the amount of moisture in contact with the tablet. To ensure fast phosphine production, always wrap the tablets in moist paper just before putting them in the warren.
Method of application
- Step 1. Make enough noise or work the area with dogs to encourage rabbits to go underground.
- Step 2. Cut back around the hole to provide adequate depth for the soil plug to close the opening later.
- Step 3. While wearing PVC gloves, place one or two aluminium phosphide tablets wrapped in moist paper at least 60cm down a tunnel.
- Step 4. Place a ball of crumpled paper down the opening. This will prevent loose dirt from covering the fumigant tablets. Block the entrance with a mallee root or something similar.
- Step 5. Fill the opening with soil and trample down to give a good seal.
- Step 6. Repeat steps 2-4 until all warren entrances are sealed.
Always start downwind and work your way into the wind to avoid accidentally inhaling any gas.
Inspect the warrens one week after treatment and retreat if necessary.
Phosphine generating products are produced under several brand names and are available to primary producers from rural merchandise suppliers.
Be careful with phosphine
Phosphine is lethal to all forms of life. Read the label and follow the manufacturer’s instructions carefully. Phosphine is extremely dangerous in enclosed spaces such as vehicle cabins.
Always open the phosphine container in the open air – not in a shed or the car. Stand upwind of the container and hold it away from your face when opening or applying the tablets. Never open the container close to flammable materials.
Wear PVC gloves and breathing protection (combined dust and gas cartridge and respirator). Wash your hands afterwards.
If poisoning occurs, contact a doctor or the Poisons Information Centre (131 126). Do not give direct mouth to mouth resuscitation if swallowed. To protect rescuer use Air-viva, Oxy-viva or one-way mask. Resuscitate in a well-ventilated area.
For further information on rabbits and rabbit control, search our website, or contact the Pest and Disease Information Service.