Global Extinction Crisis
Nature & People
The Earth is experiencing the 6th massive extinction event of its evolutionary history – the 5th was 65 million years ago. The Red List published by the International Union for Conservation of Nature and Natural Resources states 25% of mammals, 13% of birds and 33% of amphibians are in danger of extinction. The current era is unique as the speed and breadth of extinctions is being caused by the actions of people. The current rate of species extinction is estimated to be 1,000 times greater than it would have been under the influence of natural disturbances.
The conservation status of Australia's biodiversity reflects the global situation. Close to 50% of all mammal extinctions that occurred globally in the last 200 years were in Australia. 3 bird species, 4 frog species and 61 species of flowering plant have become extinct since non-Indigenous settlement began. Australia's biodiversity crisis is evidenced by the number of native species that have seriously declined in range and abundance since the 18th century.
Approximately 13% of all Australia's known vertebrate species are listed in Australia's Environment Protection and Biodiversity Conservation Act 1999 as either 'threatened' or 'vulnerable'. The number of terrestrial birds and mammals assessed as extinct, endangered or vulnerable on this list rose by 41% in the last decade.
Known species extinctions Australia has experienced since non-Indigenous settlement have been primarily in arid/semi-arid climatic areas, however, significant loss of biodiversity has occurred in the forests and woodlands. The extinction of local populations and community assemblages continues with the degradation of ecosystem functionality. This local loss of biodiversity is partly recognised by the species and ecosystems formally regarded by each Australian state as threatened, as distinct from those listed nationally as threatened with global extinction.
The Great Eastern Ranges corridor is crucial if we are to keep common species common and maximise opportunities for our richest assemblage of biodiversity to adapt and move if necessar as climate changes. Due to its length, intactness, elevation and latitudinal range, nowhere else in Australia does the landscape structure provide this opportunity. It is an opportunity that can be grasped by this generation or be lost as population grows and further fragments the outstanding natural values of the corridor.
