An extensive 14-year survey to record koala sightings in Campbelltown in south-western Sydney is an excellent indicator that koalas are likely to exist in other parts of western Sydney, according to Associate Professor Robert Close, a wildlife scientist at the University of Western Sydney.
In a research paper called 'Southern Sydney's urban koalas: community research and education at Campbelltown', Dr Steven Ward and Associate Professor Close have found that shale-sandstone transition forest is the preferred vegetation for koalas within the Georges River catchment.
"There is only a small population of around 200 koalas in Campbelltown and we have found that these koalas do particularly well in areas which have shale-sandstone soil, which is the type of soil present in a narrow strip of land between the urban areas of Campbelltown and the Georges River."
Areas with Cumberland Plain vegetation are also very likely to have been koala habitat. Such vegetation exists at the ADI site at Penrith, Associate Professor Close says.
"These areas have shale soils which are potential locations where koalas could make a comeback on the edges of the Sydney basin," he says.
"Suitable habitat still exists elsewhere such as Kurrajong, lower and upper Blue Mountains - and we've had a few koala sightings in these areas. "National Parks and Wildlife Service surveys have recently discovered koala colonies in the Warragamba catchment and we know there are koalas in Kuringai Chase and in the Avon Dam area.
"We began looking for koalas in Campbelltown and we've expanded our interest all around western Sydney and we have an ongoing interest in koalas in Avalon/Palm Beach. Avalon had a colony until 1970s and then numbers plummeted. With the help of residents we are hoping to locate and tag any remaining animals in Avalon.
"So we have koalas in several localities around the Sydney basin, even though vegetation has already been extensively cleared. What remains of Cumberland Plain and shale-sandstone transition forests needs to be preserved along with any vegetation corridors linking the remnants.
"The ADI site is a large expanse of vegetation, and almost untouched for many years. This area presents a challenge as it is closed to the public. However, we plan to approach the Delfin Lend Lease for their involvement in allowing us, as experienced koala researchers, to visit the site and look for the presence of koalas in the area."
Associate Professor Close believes that planting trees in residential areas is worthwhile in already cleared areas, especially planting local feed trees such as the Grey gum, Eucalyptus punctata, and the River red gum, E. tereticornis. These are large trees and local councils need to take the initiative and plant these trees where there is suitable space.
"There is the potential for koala numbers to recover where there is suitable vegetation - even when the population seems to have been lost. We are getting more sightings in the Kurrajong and Colo River areas - green belts could be a key in keeping vegetation links to enhance the chances for population to increase or recover."
Major problems with development are not just the land clearing but additional impacts such as erosion, weeds, altered fire regimes and deaths from vehicles and dogs.
"We need intelligent development of already cleared areas - intelligent development is replanting local natives, controlling dogs, rubbish and trail-bike riders and restoring the natural under-storey."
"Restoring degraded urban bushland and maintaining a suitable fire-regime that balances the needs of the bush with the risk to people and property is a difficult task. That's why current and future land development presents a real danger for any wildlife that may exist in these areas.
"We need stricter controls on development near native habitats to decrease the rate of habitat loss.
"Conserving any remaining vegetation and maintaining links to other populations in western Sydney through native vegetation links is crucial to the long-term survival of native animals.
"Residents across western Sydney can report any koala sightings. I encourage anyone who has seen koalas on the fringes of the ADI site and anywhere on the edges of the Sydney Basin to contact the University of Western Sydney koala hotline on (02) 9962 9996."
To mark National Save the Koala Day (July 30) and Koala month, Associate Professor Close will give a talk on 'Koalas Conservation and Survival ' at the Avalon Community Centre on Friday evening, from 7.30pm on July 30.
He will discuss the history of koalas in the Sydney basin, the 'vanishing colony' at Pittwater and how his research team is working with the community to discover if there are any koalas left.
The Coastal Environment Centre and Pittwater Council will host the event.
For more details about the talk, contact Cathy Hemery on 99706905.
Senior Media Officer
02 9678 7086, 0414 308 701
To: Story list
This page is maintained by the UWS Media Unit.