RABBIT WARREN MAPPING – A JOINT PROJECT
It’s 7am on a surprisingly chilly morning in late Summer. We’re up on the shoulder of Mount Ainslie, armed with a precious GPS unit, orange tape, folder, thermos (old softies, we are) and ready for a long wait, if necessary.
Yes, it’s a stakeout! Somewhere on, or near this shoulder we know there must be a rabbit warren, from the number of recently used buck heaps. Several previous searches have failed to uncover so much as a single burrow. But we’ve got the bug! Discovering those ominous holes in the ground is deeply satisfying and yes, addictive! If we can’t locate the warrens, then we’ll lie in wait for the furry inhabitants to give us a few clues…… or so we thought! But like the early bird, the rabbits had already come and gone, breakfast over. Conceding round one to the bunnies, we resorted to another painstaking search around the area, finally locating a couple of well concealed warrens.
The rabbit warren mapping project conducted in the summer of 2008/2009 in the nature reserves of North Canberra generated a very high level of enthusiasm and commitment from volunteers. Three neighbouring ParkCare groups worked together – the Friends of Mt Majura, the Mt Ainslie Weeders and the Watson Woodland Working Group. The need for action was clearly evident. A rapid increase in the rabbit population over the past years was impacting heavily on natural regeneration and native ground cover, leading to increased weed invasion and erosion in the reserves. It was also undermining much of the revegetation work done by ParkCare groups. In a public lecture on rabbits organised by the Friends of Mt Majura (FoMM), Dr Brian Cooke of the Invasive Animals Cooperative Research Centre at the University of Canberra said that one rabbit per hectare prevents natural regeneration of palatable native species, yet we had recorded 2.57 active rabbit warrens per hectare, some with 20 odd entries, in the Majura paddocks and an average of 1.9 warrens per hectare in the total area mapped by volunteers.
In 2008 FoMM lobbied the ACT Government for funds, eventually convincing Jon Stanhope of the need for adequate funding of a rabbit control program. With rabbit control a high priority, rangers from Parks, Conservation and Lands (PCL) had begun work on locating and mapping warrens, but limitations on staff time meant a comprehensive survey was not possible. Need and opportunity came together, with PCL staff and local volunteers combining forces.
Using Google Earth, the targeted area was broken down into manageable plots usually bordered by landscape features such as tracks or fences. Since attempts to locate warrens on printed maps failed we decided to use Global Positioning Systems (GPS) to record the warrens. Some volunteers had their own GPS and additional units were borrowed from PCL, the Molonglo Catchment Group and private sources. Inexperienced volunteers were trained by those with experience and rose to the challenge of mastering a new technology. Volunteers received some valuable training from PCL staff to identify active warrens and burrows and worked in pairs or small groups on allocated plots.
The mapping process was hard work! Working largely in the heat of summer, volunteers usually set off in the early morning to scour the hillsides and gullies, their skill increasing rapidly with each expedition. Sites were located and clearly flagged with orange tape, waypoints established and detailed field notes recorded. At the end of an exhausting session, it was both sobering and yet deeply satisfying to see so much orange tape flapping from trees and undergrowth. Close to 1500 warrens were mapped, from Federal Highway in the north right through to Fairbairn Avenue in the south. After locating one particularly well concealed warren one mapper was heard to chuckle, “Aha! Now I’m starting to think like a rabbit!”
The coordination of a project such as this requires very high level organisation and management skills. From start to finish the project was managed by the coordinator of Friends of Mt Majura, the indomitable Waltraud Pix. Waltraud liaised, recruited, trained, organised, monitored, encouraged and finally, downloaded a huge amount of data. She thought of everything – and a whole lot more.
Once the mapping process was complete, the data assisted rangers and contractors to quickly locate and treat warrens with heavy machinery or fumigation. In some areas, rabbit numbers have been reduced by 85 per cent, a very satisfying result for an initial project.
A partnership such as this has benefits extending beyond the original goal. Volunteers have enjoyed the privilege of working with, and learning from PCL staff. A greater sense of collaboration has developed between the three ParkCare groups, with further combined activities already occurring. The local community has benefited through increased awareness of environmental activity in their region.
Fortunately funds are available for a second round of mapping and control in 2009/10. Our dedicated mappers can hardly wait to charge up their batteries and begin.
Mt Ainslie Weeders