Climate Change And The Wombat State Forest: A Greenhouse Refuge?

By Tanya Loos

Eastern yellow robin

Where to? Eastern yellow robin (photo by Graeme Chapman)

There has been an average of a 0.6 C° rise in temperature globally in the past one hundred years, and there is an absolutely vast body of evidence out there recording the changes in habitats of f lora and fauna as a result of Climate Change. Of course, this temperature rise has been accompanied by changes in precipitation (more rain in parts of the world such as Europe and less rain in places such as our part of Australia), changes in large scale meteorological phenomena such as El Nino, the North Atlantic Oscillation and in sea level rise. All of these factors, plus the pressures of continuing habitat destruction, hunting and competition with the several billion humans, are having profound effects on global biodiversity, and even commonly seen birds and animals are declining in areas such as Europe.

Here in Australia, we are seeing changes in range, as formerly northern area birds extend their ranges southward. For example, White-headed pigeons are now observed west of Melbourne. Unfortunately these extensions in range are accompanied by a reduction in the northern part of their range. Climate Change in Australia is likely to mean a continuation of what we have already seen in the past few years, including increased drought and decline in winter rainfall, unpredictable weather such as severe storms and wind and less frosty days. In Australia there has been an increase of land surface temperature of 0.9 C°.

A recent report by Birds Australia “Birds In A Changing Climate 2007” identified the following habitats as at special risk from the effects of climate change: freshwater and wetland habitats, sub-tropical and tropical rainforests, alpine areas, woodlands, the drier, flatter areas of the continent, mallee, and coastal habitats such as saltmarshes and near coastal low lying dunes and plains.

Whew! What does that leave us with? Mid elevation or foothill forests! A study in 1995 identified a number of areas in Victoria that will probably fare better under the effects of climate change, and called these areas “greenhouse refugia”. One of these areas was in fact the Wombat Forest! Other areas are in the Otways, and Gippsland.

So what are the implications of the Wombat State Forest and its associated parks being a greenhouse refuge? Perhaps the struggling woodland birds of the plains will manage to shift their ranges and survive in the Wombat. Certainly, even now, birds that are common here such as the Rufous and Golden Whistlers, Scarlet Robin, and Buff-rumped Thornbill are not faring so well in woodland areas.

If the Wombat is regarded as a greenhouse refuge, it means that on a statewide scale, this area is actually very very important ecologically, and should be managed as such. It needs one governing body, such as Parks Victoria, and its moister and riparian areas such as Damp Forest and Sedgy Riparian Woodland EVC’s should be managed sensitively as a matter of priority.