Macedon Ranges Conservation Society

Except from:

Macedon Ranges Conservation Newsletter - September 2002.

 

Koala surveys conducted over 30 years on and around Mt Macedon have shown that populations of Koalas has declined by 85% by 2002 (MRCS).

While the exact reasons for this decline can yet to be conclusively demonstrated, it is likely that increased human development and the resultant loss of habitat, increased vehicular traffic and increased dog populations are likely to be significant factors.

The situations has become such that every area of the Shire now supporting Koalas is critical. By all indications, numbers are still declining, and unfortunately, this is looking alarmingly like a local extinction process.

Koala counts in the early 1970’s recorded up to 270 Koalas in the Macedon Range. In 1979 only 107 were found – half the numbers seen 7 years earlier! After Ash Wednesday a count in 1984 recorded equally low numbers especially in the Regional park.

Our count in 1994 confirmed this spiralling downward trend with only 41 animals counted despite twice the numbers of searchers following the same tracks.

This last count was in 1997 and the MRCS has decided to organise another count in November. A lot of effort goes into planning to be and running this event. There are about 60 tracks to be walked in the Mount Macedon area by volunteers who walk in twos or small groups so obviously many people are needed on the day.

Pressures on the Koala in the last 10 years include increase in fuel reduction burning, clearing for trees for development, dogs, a Koala disease and an alarming increase in the numbers killed on roads.

 


 

 

  Macedon Ranges Conservation Society newsletter -September/October 2004.

 

MRCS surveys since 1970 have shown an alarming decline in Koala numbers in the Macedon Ranges. Recent surveys indicate that the koala population has levelled off at less than a quarter of the numbers in the first surveys. The causes of this decline are unknown but we suspect that something is interfering with the breeding of the koalas. It is now uncommon to see females with young on back. This decline seems to be most apparent on the western side of the range which has become more closely settled.

                                                                                                                                                                                                                    Results of MRCS surveys of koala numbers in the Macedon Ranges.

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New bench mark needed.

The surveys to date have used volunteer walks or drivers to count koalas observed on 75 designated routes on a particular day. In addition, residents were asked to report koalas seen on their properties the same day. This technique can give an estimate of total numbers only when there is a relatively high population density.

With current low numbers, this method becomes unreliable with uncontrollable variables giving misleading results. The 2002 result can’t be interpreted as showing an increase in koala numbers. Another problem is that many of the 75 standard routes are now inaccessible due to overgrowth of vegetation and residential development.

To obtain valid and reliable results we need to have a small number of trained observers carry out more frequent surveys using scientific sampling methods. We can still involve wider community by continuing with the survey of property owners.