The best time to combat rabbits is now
Best practice rabbit control should involve a sequence of multiple control methods which, in southern Australia, is best carried out in late summer-autumn, prior to their breeding. Land managers should not view the rabbit haemorrhagic disease virus (RHDV) biocide as a ‘silver bullet’.
Did you know?
- European rabbits are Australia’s most widespread and destructive agricultural and environmental vertebrate pest.
- In general, about 9–12 rabbits/ha is equivalent to one DSE (dry sheep equivalent).
- With no control, one pair of rabbits may become 184 pairs in just 18 months in good conditions.
Infesting two-thirds of Australia, and almost all wool-growing regions, rabbits cost Australia on average $197 million a year in lost farm productivity. They affect wool-growing productivity due to lower stocking rates and/or reduced sheep weight gains, wool cuts and birth rates.
Rabbits are also implicated in greater lambing losses through supporting increased fox populations and lamb predation rates, and livestock leg injury or breakage in rabbit burrows. They can be a host for parasites and diseases, and are linked to increases in weeds.
Rabbits are the single biggest menace to threatened native species; they are a key threat to 322 nationally listed threatened species of native plants and animals. Their digging and browsing can also result in slope instability and soil erosion.
Effective management of rabbits is essential to protect agriculture and the environment. Since the early 1970s, integrated pest management (IPM) has been recommended as a means to not only efficiently reduce rabbit numbers, but also achieve their complete elimination at local scale, reducing the need and cost to frequently reapply control.
IPM is not just about applying multiple controls; they must be applied in a sequence and at a time of the year that makes economic and ecological sense.
Apply multiple control methods in sequence
The sequence of control methods is critical for achieving a high level of rabbit management.
Furthermore, the control methods should be applied in as short a time sequence as feasibly possible, although sufficient time must be given for the first applied control method to have impact before the second control method is applied.
1. Population knockdown
The first step is to reduce the rabbit population from medium–high densities down to a manageable level. This is usually done by biological control (via natural outbreak or deliberate release) and/or chemical control (e.g. a poison baiting program) during the non-breeding season.
Although myxoma virus is no longer produced commercially, myxomatosis is still important for rabbit control in Australia.
RHDV is the current biological control and can be deliberately released in some areas, subject to state and territory legislation.
If RHD or myxomatosis are already present, then poison baiting should be delayed to allow the disease to reduce rabbit numbers. If rabbit density is low then extensive control can be started straight away.
2. Extensive control
The next part of the control program should destroy all source areas (where rabbits are living) and reduce rabbits to very low numbers. Control activities include warren ripping and destruction/removal of harbours which provide rabbits with shelter, such as fallen logs, building debris or dense vegetation. Where the use of heavy machinery is not an option for warren ripping, alternative techniques such as explosives may be used.
Extensive control ensures that the rabbit population cannot recover quickly but it must be done thoroughly to ensure success. If any warrens or harbour are not destroyed, rabbit numbers will simply build up again. Sometimes rabbits can also dig back in and ‘re-open’ warrens if ripping is not done thoroughly (deep or wide enough) and the collapse of the warren structure is inadequate.
3. Mop-up activities
There are usually small numbers of rabbits that survive extensive control, so advanced control is necessary for long-term management. This is where follow-up techniques such as warren fumigation, shooting and trapping are used in rabbit-active areas.
Timing is crucial
Applying control activities at the right time of the year is as important as the sequence through which controls are applied.
The implementation of integrated rabbit management in late summer-autumn (February-May), immediately prior to breeding and before winter rains begin, is a well-established recommendation for rabbit control.
This is consistent with when rabbit numbers are naturally at their lowest in their annual cycle and food is short, making rabbits more likely to consume baits treated with RHDV, pindone or 1080. This timing also facilitates effective warren ripping in light soils by improving the flow of soil into burrows to ensure their collapse.
It is important to note that RHDV should only be released when young rabbits are not present. This is because they do not develop acute disease and are immunised rather than killed by RHDV infection, thereby exacerbating Australia’s rabbit problem.
Therefore, RHDV should NOT be released across southern agricultural Australia between July and December (i.e. when young rabbits are likely to be present) unless land managers are confident rabbits are not breeding and young rabbits are not present. The optimal time of release is generally considered to be the end of summer or start of autumn (February, March, April), before any major autumn rainfall that might kickstart rabbit breeding.
The AWI co-funded, 36-page Glovebox Guide for Managing Rabbits provides useful information on best practice rabbit management for farmers and other land managers. Access the guide and other rabbit control related information on the PestSmart website at www.pestsmart.org.au.
Top photo credit: John Schilling.
This article appeared in the Autumn 2025 edition of AWI’s Beyond the Bale magazine that was published in March 2025. Reproduction of the article is encouraged.
