Next-generation invaders? Hotspots for naturalised sleeper weeds in Australia under future climates

PLoS One. 2013 Dec 26;8(12):e84222. doi: 10.1371/journal.pone.0084222. eCollection 2013.


Naturalised, but not yet invasive plants, pose a nascent threat to biodiversity. As climate regimes continue to change, it is likely that a new suite of invaders will emerge from the established pool of naturalised plants. Pre-emptive management of locations that may be most suitable for a large number of potentially invasive plants will help to target monitoring, and is vital for effective control. We used species distribution models (SDM) and invasion-hotspot analysis to determine where in Australia suitable habitat may occur for 292 naturalised plants. SDMs were built in MaxEnt using both climate and soil variables for current baseline conditions. Modelled relationships were projected onto two Representative Concentration Pathways for future climates (RCP 4.5 and 8.5), based on seven global climate models, for two time periods (2035, 2065). Model outputs for each of the 292 species were then aggregated into single 'hotspot' maps at two scales: continental, and for each of Australia's 37 ecoregions. Across Australia, areas in the south-east and south-west corners of the continent were identified as potential hotspots for naturalised plants under current and future climates. These regions provided suitable habitat for 288 and 239 species respectively under baseline climates. The areal extent of the continental hotspot was projected to decrease by 8.8% under climates for 2035, and by a further 5.2% by 2065. A similar pattern of hotspot contraction under future climates was seen for the majority of ecoregions examined. However, two ecoregions - Tasmanian temperate forests and Australian Alps montane grasslands - showed increases in the areal extent of hotspots of >45% under climate scenarios for 2065. The alpine ecoregion also had an increase in the number of naturalised plant species with abiotically suitable habitat under future climate scenarios, indicating that this area may be particularly vulnerable to future incursions by naturalised plants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Australia
  • Climate Change
  • Climate*
  • Ecosystem
  • Introduced Species / statistics & numerical data*
  • Models, Statistical*
  • Plant Weeds / growth & development*
  • Soil


  • Soil

Grant support

This work was funded by the National Climate Change Adaptation Research Facility. We thank the Department of Biological Sciences at Macquarie University for financing this open access publication. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.