Melissa Fyfe, Environment Reporter, May 10, 2004
The State Government has admitted that it lost control of five fires connected to logging operations, most of them in Melbourne's water catchments.
One fire incinerated several boxes that forest animal specialist David Lindenmayer had set up as experimental habitats for the endangered Leadbeater's possum. It is believed possums were not using them at the time.
Two post-logging fires escaped into national park in the O'Shannassy and Maroondah areas - "locked" parts of the city's water catchments. Two other fires in April, also lit to regenerate logged areas, burnt 280 hectares of the Thomson catchment, one of the city's major water sources.
Logging in water catchments is sensitive because it replaces old trees with young trees which, while growing, suck up water that would otherwise flow to dams. Melbourne Water research shows that water yield from logged areas drops 50 per cent by the time the trees are 20 to 30 years old. For this reason, the Department of Sustainability and Environment and Melbourne Water only allow 150 hectares to be logged each year in the Thomson catchment. A fire, which also encourages young trees to grow, also has a water-reducing effect.
A department spokeswoman said the two fires that escaped into the Yarra Ranges National Park were minor. In the Maroondah catchment, a quarter of a hectare was burnt, and half a hectare in O'Shannassy, she said.
"These escapes occurred during the extreme weather conditions experienced post-Easter," she told The Age. Another controlled burn got away in a special forest experiment, also part of Professor Lindenmayer's work. In a logging area, an island of trees that was supposed to be left for future animal habitat was burnt. But the spokeswoman said: "At Toolangi the regeneration burn did get into the island, but the mountain ash will survive and provide animal habitat in the future."
Professor Lindenmayer is helping research ways that clearfell logging can be changed to leave clumps of forest that will grow old and provide hollows, key habitat for Leadbeater's possum.
"Essentially we have a big problem in the Central Highlands with clearfelling," Professor Lindenmayer said. "It eliminates the structural complexity of the forest ... There needs to be a mixture of old trees and young trees."
Professor Lindenmayer, from the Centre for Resource and Environmental Studies at the Australian National University, said he did not know how many possum boxes he had lost. The experiment - to see if they would live in boxes in the absence of suitable hollows - had not attracted possums so far.
The Wilderness Society and local conservationists believe that logging should be stopped in Melbourne's water catchments.
Sarah Rees, the Central Highlands Alliance president, said her group had stumbled on the "smouldering secret" in water catchment areas. "The (department) has displayed nothing but nonchalance and disregard for the sensitivity of these surrounding national parks," she said.