Conservation of biological diversity

Biological diversity is the variety of life forms: the different plants, animals and microorganisms, the genes they contain, and the ecosystems they form. It is usually considered at three levels: genetic diversity, species diversity and ecosystem diversity. The ultimate objective of the conservation of biological diversity is the survival of species and the genetic variability within those species.

The nine indicators in this criterion are divided into three subcriteria: ecosystem diversity, species diversity and genetic diversity. Ecosystem diversity indicators describe the range, extent and growth stages of Australia's forest types, the tenure systems within which they are managed, the level of forest clearing and the extent to which such clearing has fragmented native forests. Species diversity indicators are concerned with the number and variety of forest-dependent animal and plant species; indicators in this subcriterion identify forest-dwelling species, the level of information to support conservation strategies, and the role of forest management in protecting threatened and vulnerable species. Genetic diversity indicators examine the risk of genetic diversity loss in forests and the measures in place to minimise that risk.

Key findings for forest ecosystem diversity

• Australia has 149 million hectares of forest. Of this, 147 million hectares is native forest, dominated by eucalypt (79%) and acacia (7%) forest types. There is 1.82 million hectares of plantations, mostly comprising 1.0 million hectares of pine (softwood) and 0.81 million hectares of eucalypt (hardwood), an increase of 12% over the 1.63 million hectares reported in Australia's State of the Forests Report 2003 (SOFR 2003).
• Australia's ability to estimate its forest area continues to improve with the increasing availability of high resolution remotely sensed data and improvements in forest typing methods. This largely explains the revision of estimated total forest area from 164 million hectares in 2003 to 149 million hectares reported here; little of the change is due to real forest loss.
• Since 2003, the area of native forest in formal nature conservation reserves has increased by about 1.5 million hectares to 23 million hectares, from 13% to 16% of Australia's forests. The area of multiple-use public forests (in which wood production is an objective) declined from 11.4 million hectares in 2000-01 to 9.4 million hectares in 2005-06.
• Seventy per cent of the total forest estate is privately managed, including private freehold, leasehold and Indigenous-managed lands.
• The net loss of woody vegetation (mostly forest) estimated by the Australian Greenhouse Office (AGO) was 260,000 hectares (0.25%) per year between 2000 and 2004, due mainly to clearing for agriculture and urban development. The rate of loss of woody vegetation is declining in response to changed land management practices and increased legislative controls. Of the 23 million hectares of forest assessed for oldgrowth values, 5.03 million hectares (22%) is classified as old-growth. This is about 200,000 hectares less than that reported in 2003 (5.23 million hectares), due mainly to the impact of severe fires, with younger forests replacing some old-growth forest, and also to some remapping. Over 70% of known old-growth forest is now in nature conservation reserves.
• The area of forests in formal nature conservation reserves increased for most forest types over the reporting period, with notable increases in some types, including rainforest (from 33% to 55%) and mangroves (from 13% to 18%).
• There has been an increase in the area of privately managed forest (including private freehold, leasehold and Indigenous-managed lands) managed for conservation objectives through a variety of national and jurisdictional programs, but the extent of this increase is not well documented.
• As much as one-third of Australia's native vegetation in the intensively managed agricultural and urban zones has been cleared or substantially modified over more than 200 years of European settlement. As a result, those areas exhibit a relatively high level of fragmentation.
• A review of fragmentation in two regions between 1972 and 2002 suggests that fragmentation can be dynamic, even in nature conservation reserves, with changing patch sizes and spatial arrangements of different forest types.
• The cessation of broadscale clearing in much of Australia and increased protection of forests have been critical in reducing forest fragmentation in recent times.

Key findings for forest species diversity

• The number of known forest-dwelling species increased from 1998 to 2006, reflecting improved information. Partial ecological information is available on around 60% of forest-dwelling vertebrate and vascular plant species and comprehensive ecological information is available on at least 10% of mammal, bird and amphibian species, but very limited information is available on forest-dwelling invertebrates, fungi, algae and lichens.
• A total of 1,287 forest-dwelling species are listed under the national Environment Protection and Biodiversity Conservation Act 1999 (Cwlth) (EPBC Act) as vulnerable, endangered or threatened. Thirty-nine species or subspecies were removed from the list during the reporting period, and 67 were added.
• Most additions of forest-dwelling species to the national list of threatened species were made based on inherently small population sizes and ongoing impacts on habitat extent and quality, including the impacts of introduced species and unsuitable fire regimes. Most removals of forest-dwelling species from the list were made as a result of improved information.
• Birds are the taxonomic group with the largest number of programs in place to track population trends. State and territory efforts are supplemented by a large-scale investment by non-government groups.
• The lack of comprehensive knowledge on the occurrence of representative species across land tenures and broad forest types limits the conclusions that can be drawn from available data.

Key findings for forest genetic diversity

• While the number of forest-associated species for which data on genetic variation are available is still very small, it has increased since SOFR 2003. Then, data were available for one faunal and two floral species; now, data are available for more than 10 faunal and 13 floral species.
• Several studies have documented genetic variation and distribution patterns within existing populations of a relatively small number of forest-associated species. Several institutions have programs to measure genetic diversity in forest fauna, but nationally conclusive results are available for only a few species.
• Conservation measures focus on increasing connectivity between isolated patches of native vegetation, increasing the area of forest contained in public and private nature conservation reserves, managing threats to native species, and assisting the recovery of threatened species.
• Genetic resource conservation plans exist for more than 40 native timber and oil-producing plant species, a 70% increase on the number reported in SOFR 2003. The increase includes species used in farm forestry in drier environments.
• Tree-breeding and genetic improvement programs are expanding the scope for conserving native forest genetic resources, including non-commercial endangered species. Selective harvesting in multiple-use public forest.

Full report for Criterion 1 - Conservation of biological diversity [pdf 4.1MB]