The Cumberland Livestock Health and Pest Authority is set to undertake a broad scale release of rabbit hemorrhagic disease (RHD) across the northern Sydney region in a major effort aimed at reducing the ecological impact of urban rabbit populations.

The release of RHD, also known as rabbit calicivirus, will take place in late February when there is improved likelihood of the virus spreading via flies and mosquitoes.

Working with the Cumberland LHPA on the project is the National Parks and Wildlife Service and local councils including Manly, Ku-Ring-Gai, Pittwater, Warringah, Ryde, Parramatta, The Hills, Hornsby, Lane Cove, Taronga Zoo and Sydney Harbour Trust – all of which are areas with significant rabbit populations.

Ranger for the Cumberland LHPA and project leader, Steve Parker says there has been a scientific approach to the project to help ensure its success.

"For the release of RHD to work the environmental conditions need to be favourable and there should be no (or very low) resistance to the disease in the rabbit population," Mr Parker said.

"During early summer, we took blood samples from a number of rabbits across the region to test for RHD antibodies.

"Once we found the results were all negative, we planned our release date based on the prevalence of vectors – late February is a good time due to the increased number of flies and mosquitoes to spread the virus."

The virus will be released on carrot baits throughout bushland reserves and national parks in the northern Sydney region, from Parramatta to Pittwater.

"This is an area where baiting rabbits with poisons such as Pindone is normally restricted, but with RHD we are not limited to these confines as RHD will not affect other animals or humans," said Mr Parker.

Domestic rabbit owners are urged to have their rabbits vaccinated for RHD annually.

Mr Parker is optimistic that the release of RHD will be successful in lowering wild rabbit numbers in the target area, greatly reducing the environmental impact of these pests.

"We undertook a similar project last year in the same region which resulted in a significant reduction in rabbit numbers," Mr Parker said.

The project fits within the guidelines of the Sydney North Rabbit Management Plan 2007-2010.