Study looks at maintaining viable forests
By Shelly Simonds Australia's forest plantations are expanding rapidly. Now an ANU project is looking at how large plantations can be designed so that they retain some value as habitats for native fauna. With one of the highest rates of mammal extinction in the world and vegitation clearing rates rivalling those in parts of Indonesia and the Amazon basin, Australia needs more information on how to better manage its remaining forests, said Dr David Lindenmayer, a CRES Fellow. He is investigating the benefits to biodiversity of retaining patches of remnant native forests in large commercial plantations, as part of the Tumut Fragmentation Experiment which began in 1995. "The process of plantation establishment is happening all across southern Australia. We need to have better information to guide and inform the process," Dr Lindenmayer said. The project looks at patches of eucalypt forest that were spared when large pine plantations were established in the Tumut area over the past century. Large areas of national park nearby allow for direct comparisons between fragmented and unfragmented forest systems. The remnant patches vary in size. The fragmentation project team - including Craig Tribolet, Chris McGreggor, Henry Nix, Matthew Pope, and Mike McCarthy as well as Ross Cunningham and Christine Donnelly of the ANU's statistical consulting unit - has found that larger patches have a higher probability of providing habitats for arboreal marsupials. However even small patches of remnant forest can provide an important habitat for birds and mammals. Good vegetation makes patches preserved along gullies especially important for the dispersal of small native mammals. "Gully lines attaching big patches of forest are the go," Dr Lindenmayer said. "These patches do have value and this value can be maintained if you plan plantations properly." Another surprising finding was that pine forest plantations can support significantly more native species of birds than previously thought. The Fragmentation Experiment has been supported by the State Forests of NSW, NSW National Parks and Wildlife Service, Land and Water Resources and Research Devel- opment Corporation and the Australian Research Council. Groups like the Canberra Ornithologists have also been a key part of data collection and result reporting. Dr Lindenmayer has recently completed another major project with Mark Burgman, of the University of Melbourne. Their book Conservation Biology for the Australian Environment is the first textbook on conservation biology focused on Australian data and case studies. It will be released in September.