Canberra Nature Parks south district ranger Nina Bruns said warren numbers had fallen by more than two-thirds at Mount Ainslie and Mount Majura in the past two years.

''Mount Ainslie and Mount Majura was one of the really problem areas we had, and about two years ago our ParkCare volunteers mapped over 900 warrens,'' she said.

''This year we have found only 250.''

Ms Bruns said different districts used different methods, with seasonal factors also relevant.

''We usually do baiting during the summer months because rabbits are more likely to eat a juicy carrot when it's dry, and in winter we use fumigation of the warrens when the rabbits are more underground and after the breeding season,'' she said.

From now until early winter, rabbit control work including baiting using poisoned carrots, oats and cages will be conducted in parks and reserves in Canberra's north and south.

Ms Bruns said numbers of killed or current rabbits were not known, as sick rabbits would go into their warrens before dying and decomposing.

She said the carrot bait was dried blue so it was not attractive to birds, but pets including dogs should be kept away.

''It would get sick but it would be fine with an injection … (we) haven't had pet incidents that I'm aware of,'' she said.

ACT Parks and Conservation Service director Daniel Iglesias said rabbits created erosion and if left uncontrolled invaded the surrounding area, including backyards.

''Rabbits are a serious environmental pest, eating down the ground layer vegetation so it no longer provides food and shelter for various other species such as reptiles and ground-feeding birds.''

He said to date the government's rabbit control program had received strong support from the local ParkCare groups.

''Volunteers from numerous ParkCare groups have spent over 1000 hours mapping warrens across numerous reserves using handheld GPS devices,'' he said.

''This allowed government staff and contractors to move through the reserves using nationally recognised techniques to control the rabbit population.''

Following many years of targeted controls, the current work is part of a $150,000 ACT government program to cut populations in nature reserves in 2012-13.

Signs will be put in place at the entries to areas where rabbit control is being undertaken and on baiting cages to alert people.

Mr Iglesias said users of these areas are requested not to touch or interfere with poisoned carrots, oats or caged bait stations.

He said control work does not pose a risk to public safety but domestic animals should be kept away from the control areas.

Southside locations

Northside locations