Southwest Australia Forests and Scrub
Imperiled: The Encyclopedia of Conservation
School of Science
Southwest Australia is an internationally-renowned biodiversity hotspot containing over 8000 plant species, 47 % of which are endemic, as well as many endemic animal lineages. It is recognized as a Global Biodiversity Hotspot by Conservation International and is a World Wildlife Fund Global Priority Place. Since European settlement, native vegetation has been cleared for agriculture and urban development, and remnant vegetation is currently under severe threat from the introduced plant pathogen Phytophthora cinnamomi, altered fire regimes, hydrological changes and climatic heating and drying. Consequently, around 400 taxa are threatened and 150 are critically endangered under IUCN Red List Categories, and more than 2000 plant taxa are listed as Threatened or Data Deficient by the Government of Western Australia. Here, we describe some of the region’s quintessential vegetation types; first, we introduce the spectacular karri and jarrah forests, which are under threat from logging. Then, we describe tuart and wheatbelt eucalypt woodlands, which are vulnerable to multiple threats because of the size and isolation of remnant patches, and finally, we discuss kwongkan scrub and montane thicket, which are particularly susceptible to inappropriate fire regimes and Phytophthora. Pressing knowledge gaps are posed by cascading interactions among multiple threats. However, several advantages lend hope to conservationists: the State Government has a strong history of forming cross-tenure partnerships for the benefit of biodiversity, ambitious restoration efforts spanning hundreds of kilometers are linking core habitats and enhancing landscape connectivity, and together, scientific research and Aboriginal knowledge provide a powerful foundation for ongoing conservation action.