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A commentary on Larry Carter's paper Sue Walker NSW National Parks and Wildlife Service, Grafton, NSW 2460 Larry Carter has excelled in outlining populations and genetic variation within wilderness and biodiversity from a legal, and species, so as to ensure their survival into international and Australian viewpoint. He the future. The Resource Assessment Com- also provides a useful map of wilderness in mission (1992) notes this concept for the New South Wales. I provide some comments forests: "Any attempt to maintain the bio- on one aspect of wilderness and its role in the logical and genetic diversity of the forest estate preservation of biodiversity. must seek to maintain, through time, all forest types as well as populations of their component My comments raise the New South Wales species. In addition, populations of each perspective in relation to the conservation of species must be large enough to encompass biodiversity in wilderness areas. In summary, genetic diversity within the species and to keep the remaining wilderness areas in New South the risk of extinction of each species at accept- Wales do not include all habitats or incorporate able low levels." sufficient areas of suitable habitat for many species and therefore cannot conserve Given our limited knowledge of many biodiversity alone. Wilderness, however, does species' requirements, one approach for represent the last of our large undisturbed eco- biodiversity conservation is to select indicator systems and so is critical to biodiversity conser- species. Milledge, Palmer and Nelson (1991) vation, if it is complemented by an adequate state: "To achieve conservation of viable conservation reserve system and appropriate populations of all species with confidence management practices in unreserved areas. requires knowledge of their individual distributions, abundances, ecological require- The crucial issue for the preservation of ments and population dynamics. This task, biological diversity in wilderness in Australia is given current time and financial constraints, is that viable areas of ecological units need to be beyond researchers at present. However, an included within wilderness areas. These areas approach which could offer a partial solution need to include habitat of high quality for to this dilemma is the adoption of management species conservation. In New South Wales the indicator species." Possingham (1990) also remaining wilderness areas are primarily com- considers "Managing the forest for viable prised of steep, poorer quality forests and population sizes of a small number of key woodlands. Such areas lack the essential species, may be the most economic way of habitat requirements for many species. The minimizing the loss of biodiversity. The key higher quality areas were, of course, the species should be relatively easy to study and first to be utilized by humans. The remaining represent the entire range of organisms present wilderness areas are therefore not representa- in the forests. Some potential candidates tive of the fun range of ecological communities include the Powerful Owl, the Yellow-bellied extant in New South Wales. For example, there Glider and the Platypus." Indicator species are no wilderness areas recognized on the New should be selected from each stratum and from South Wales coastal plain, except for Nadgee a range of scales in home range sizes. on the south coast. The biologically diverse north coast forests have been largely cleared, The Sooty and Powerful Owls have home fragmented and modified. The wilderness ranges of in the order of 200-800 ha and areas on the escarpment and tablelands are 800-3 000 ha per pair respectively, and if the comprised mostly of inaccessible areas of conservative minimum population of 250 pairs poorer quality, however, small remnants of tall is adopted, this necessitates conservation of at old-growth forest do remain. The preservation least 75 000 ha and 250 000 ha respectively of biodiversity will depend on wilderness of suitable habitat. Mackowski (1987) areas including a variety of viable ecosystems recommended for Yellow-bellied Gliders an and a geographical range to ensure genetic unfragmented area of 15 000 ha of suitable preservation. habitat using 250 home ranges of 60 ha each. The management of wilderness to protect Tyndale-Biscoe and Calaby (1975) note that biodiversity should be based on ecological an "effective population number is the popula- requirements of species, conserving viable tion size that will retain the original genetic December 1992 Australian Zoologist, Vol. 28(14) 37 diversity of the species, or a large fraction of it, maintenance of habitat components and eco- in perpetuity and provide the genetic means for system processes in unreserved lands is also continued evolution. It must account for essential. natural fluctuations and be large enough Wilderness areas are a premium resource for to withstand the vicissitudes of fire, disease the conservation of ongoing natural processes and drought; it is the lowest number that and provide the ideal situation to protect the population can fall to under these biodiversity. The crucial problem is that the circumstances." remaining wilderness areas do not represent The biocentric values of wilderness suitable habitat for all species and the suitable have been recognized and enshrined in the habitat that remains for some sensitive species Wilderness Act 1987 in New South Wales. The is of limited extent. Wilderness preservation section of the Wilderness act dealing with the must therefore in the future ensure that these identification of wilderness gives the definition concepts are addressed to assist biodiversity stating the value for biological conservation: conservation. Wilderness provides the best "An area of land shall not be identified as opportunity to maintain our biodiversity into wilderness by the Director unless the Director is the future if sufficient and appropriate habitats of the opinion that: are selected. (a) the area is, together with its plant and animal communities, in a state that has not REFERENCES been substantially modified by humans and BI~LOGICADL IVERSITYA DVISORYC OMMITTEE,1 992. A their works or is being restored to such a N&l Strategy /m the Cmmtim of Aurtrnlini Bio- state; logical Ixuersiq. DASET: Canbe-. (b) the area is of a sufficient size to make its Ma~c~~~o- w-s~~!C-. ~. M~.. 1,98 7. Wildlife hollows and timber management. Thesis for Master of Nat. Res., University maintenance in such a state feasible; . . ." of New England: Armidale. The remaining undisturbed lands in New MILLEDGED, . R., PALMERC,. L. AND NELSONJ, . L., 1991. South Wales have limited use for urban Barnmeters of Change: The disrribution of large owls development, forestry, intensive grazing and and gliders in Mountain Ash forests of the Victorian Central Highlands and their potential as management are likewise inadequate for the protection of a indicators. Pp. 53-65 in C m m hof Awfroliai Fmcst range of biological values. It is pertinent that Foum ed by D. Lunney. Royal Zoological Society of the remaining areas that are identified as NSW: Mosrnan. wilderness be recognized for their full range of POSINGHAMH.,, 1990. Logging and extinction: how much biological values, and that areas that are import- of a risk ran we accept? Bogong ll(3): 46. ant for biodiversity be included in RESOURCE ASSESSMENCT OMM~SSIO19N92, . Fwcsf and Tirnbcr any wilderness declaration. Nevertheless, Inquiry. Fiwl repmr. Volume 1. Australian Government wilderness alone will not protect biodiversity, a Publishing Service: Canberra. viable and representative conservation reserve TYNDALE-BlCsc. oHr., AND CAIABYJ, . H., 1975. Eucalypt system encompassing all ecosystems and the forests as refuge for wildlife. Awt. Fw. 38(2): 117-33. December 1992