Rabbit biocontrol: RHDV1 K5 national release

The national release of a Korean strain of Rabbit Haemorrhagic Disease Virus, known as RHDV1 K5 took place during the first week of March 2017.

This is the first time in 20 years that a new rabbit biocontrol agent has been released into Australia. More than 600 release sites were selected nationally. The virus was released at 110 sites in Western Australia.

The release of this new rabbit virus strain is part of a 20 year national biocontrol plan for rabbits.

Locations where RHDV1 K5 was released

As of June 2017, there have been confirmed cases of RHDV1 K5 in Bridgetown, Donnybrook, Milyeannup National Park, Esperance, Mandurah and Albany. 

Nationally, preliminary analysis based on pre and post rabbit counts from 52 release sites, has shown a 42 per cent average reduction in wild rabbit numbers at sites where RHDV1 K5 was released.

RHDV1 K5 is not a new virus. RHDV1 K5 is a naturally occurring Korean variant of the Rabbit Haemorrhagic Disease Virus (RHDV). Its release is expected to ‘boost’ current management and help slow down the increase in rabbit numbers.

RHDV1 K5 is highly contagious, can be spread by insect vectors, and other animals feeding on infected carcasses may excrete the virus.

Domestic rabbit owners are advised to seek advice from their local veterinarian and use protective biosecurity measures to help keep their rabbits safe from infection. The Australian Veterinary Association website and DAFWA’s RHDV1 K5 web pages provide further advice on vaccinations and other protective measures.

You can help

Landholders are asked to help maximise outcomes from the virus release by undertaking follow-up conventional control, coordinating any future releases at a landscape level, report rabbit sightings, and submit samples from dead rabbits for testing.

RHDV1 K5 is now available as a commercial product to authorised users, however landholders are asked to wait for late Spring or Autumn before releasing the virus.

Training and virus distribution

Winter is not best practice period for release. Late Spring and Autumn are ideal conditions for deliberate releases of RHDV1 K5, when insect activity is high, but when there are also a low proportion of very young rabbits present. 

The supply and use of RHDV1 K5 in WA to authorised users was enabled under the Biosecurity and Agriculture Management Regulations Amendment 2017 (Government Gazette Friday, 3 February 2017). Under the regulations, anyone who will be handling and mixing the liquid suspension virus must complete on-line training to become authorised users of RHDV. RHDV1-K5 Authorisation Training is available from DAFWA’s Client Online Training website.

Coordinated, landscape scale release of rabbit biological control viruses will maximise effectiveness and produce greater results than patchy, individual landholder releases. DAFWA recommends land managers contact their local biosecurity group before applying for the virus to coordinate a release or to determine if a release has already occurred within their area. Biosecurity group contact details are available within the online RHDV1 K5 training package. 

Submit reports and dead rabbit samples

The Invasive Animals Cooperative Research Centre (CRC) expects RHDV activity to increase in the coming months and the RHD Boost research team encourages landholders to report any rabbit sightings or signs of disease, and submit samples from dead rabbits.

A national approach is in place for the collection and testing of all potential RHDV+ rabbit samples. This process allows for national coordination of data, samples, messages and provides all labs access to the samples they need. This will continue for at least the next two years, and hopefully longer.

Online information can be provided (once you have a sample or samples) via the FeralScan website or the FeralScan smartphone app – available via iTunes and GooglePlay.

For any questions or technical support regarding these processes please contact Emma Sawyers on 02 6391 3834 or rhdboost@invasiveanimals.com.

Carry out integrated control

The release of RHDV1 K5 is part of a 20 year national biocontrol plan for rabbits. It will not result in a 90% reduction of pest rabbit populations, as seen with other biocontrol releases.

It is critical then that landholders undertake an integrated and complementary pest management approach, with conventional control measures put in place following release of the virus. This could include starting a conversation with neighbours with the aim of integrated best practice rabbit control at a landscape scale.

Land managers must also consider concurrent control for predators such as foxes (potentially looking for alternative food sources in the absence of rabbits). A reminder to carry out Integrated Pest Management is included on the virus product label directions and in the online RHDV1 K5 training package.

video series on best practice rabbit control has been released by the Invasive Animals CRC to increase skills in control programs. The videos include instructional ‘how-to’ videos to demonstrate control procedures such as poison baiting, baiting with biocontrol agents, rabbit warren fumigation, rabbit warren ripping and harbour destruction. It also includes video instructions for the RabbitScan (FeralScan) app and information on the RHDV1 K5 release.

Page last updated: Wednesday, 21 June 2017 - 5:05pm