In Australia, the changes in the fire regime following European settlement were a major factor in the extinction of at least five bird taxa and are a major threatening process for almost half of Australia’s nationally threatened birds.
Humans have used fire to mould the landscape and wildlife of Australia since pre-history. Aboriginal people entered the continent 60,000–100,000 years ago and used small fires for hunting and land clearance. In south-western Australia, areas were burned every 5–10 years and fires were scattered and of relatively low intensity, resulting in a mix of habitats with a high diversity of plant species. However, once Europeans took over land management, the practice and purpose of burning changed rapidly. Early European colonists burned heathland more often, every 2–3 years. This fire regime favoured the development of grasslands, which replaced other habitats and provided habitat for grazing livestock. Destructive and extensive burns were also used to aid land clearance or to show European ownership (Gill et al. 1999).
The changes in the fire regime following European settlement were a major factor in the extinction of at least five bird taxa (Gill et al. 1999). Species are lost because frequent fires alter the plant species composition and vegetation structure of their habitats (Gill et al. 1999), meaning that fire-sensitive vegetation cannot be maintained. Inappropriate fire regimes are recognised as a major threatening process for almost half of Australia’s nationally threatened birds (Garnett 1992), notably those of heathland and mallee habitats (Gill et al. 1999). One example is the Noisy Scrub-bird Atrichornis clamosus, which avoids areas that are burnt more often than every c.6 years, and reaches its highest densities only after 20–25 years of vegetation regrowth (see figure) (Smith 1985).
BirdLife International (2004) In Australia, fires are linked to habitat changes and the decline of many bird species. Presented as part of the BirdLife State of the world's birds website. Available from: http://www.birdlife.org/datazone/sowb/casestudy/125. Checked: 25/10/2014
|Key message: Human actions resulting in habitat destruction and degradation are the main causes of declines|