|
Melbourne Uni Professor counters The UBAG has received a copy of a recent letter (14 Nov, 2003) from the Minister for Environment, John Thwaites, in which he has responded to the UBAG's concerns about the management and protection (from logging) of flora and fauna values in the 350 Upper Bunyip forestry block. On the subject of rainforest, the Minister states: "The claim that rainforest could be threatened by serious runoff and/or windthrow effects from logging is unfounded. There is much scientific evidence that the protection provided by forest management plans, the Code [of Forest Practices] and local prescriptions, in the form of buffer strips, adequately restricts the flow of sediment from a coupe to a stream, protecting the rainforest. The likelihood of a windthrow event is considered negligible." This statement is at odds with information contained within a report that was commissioned by the Dept of Conservation and Natural Resources in August 1993. This report, titled Rainforest in Victoria: A Review of the Scientific Basis of Current and Proposed Protection Measures contains a preface by Richard Rawson, then Director of the Forests Service, where he states: "It was commissioned to help resolve scientific questions relating to the management and protection of rainforest stands in areas where timber harvesting is a permitted land-use. It is based on extensive research and consultation with relevant experts by its authors, Dr Mark Burgman and Professor Ian Ferguson from the University of Melbourne." The Minister's statement is so much at odds with the report that the UBAG located and approached (now) Professor Burgman for his comments on the Minister's contentions. Prof Burgman responded immediately with the following emailed reply on 20 November, 2003: "Threats posed by runoff and windthrow are a small subset of a broader class of so-called edge effects. Certainly, windthrow occurs. If harvesting activities and road crossings have a negligible effect on rainforest stream turbidity, as the Minister's statement implies, the Department should have sufficient, reliable data to support the assertion. As you rightly point out, there is good evidence that elevated temperature and changes in light, soil and atmospheric humidity result from adjacent clear felling, and penetrate forests over distances greater than those typical of Code of Forest Practice buffers. There is direct evidence of such changes over distances of 100m in Victorian sclerophyll forests, and in forests with similar architecture in other parts of the world. We could, of course, add changes in predation rates, particularly of canopy nesting birds, and avoidance behaviours in arboreal mammals. Both models and field observations in Victoria and Tasmania suggest that harvesting activities, roading and windthrow can cause local increases in rates of Myrtle Wilt. Whether one considers such changes unacceptable or not is more of a social decision than an ecological one. But there are few data measuring the magnitude of ecological consequences of edge-related physical changes in Victorian forests. I
hope this helps." The UBAG asks the simple question - Who Should We Believe? Minister Thwaites? What
is the UBAG? |