Improving transferability of introduced species' distribution models: new tools to forecast the spread of a highly invasive seaweed

PLoS One. 2013 Jun 28;8(6):e68337. doi: 10.1371/journal.pone.0068337. eCollection 2013.

Abstract

The utility of species distribution models for applications in invasion and global change biology is critically dependent on their transferability between regions or points in time, respectively. We introduce two methods that aim to improve the transferability of presence-only models: density-based occurrence thinning and performance-based predictor selection. We evaluate the effect of these methods along with the impact of the choice of model complexity and geographic background on the transferability of a species distribution model between geographic regions. Our multifactorial experiment focuses on the notorious invasive seaweed Caulerpa cylindracea (previously Caulerpa racemosa var. cylindracea) and uses Maxent, a commonly used presence-only modeling technique. We show that model transferability is markedly improved by appropriate predictor selection, with occurrence thinning, model complexity and background choice having relatively minor effects. The data shows that, if available, occurrence records from the native and invaded regions should be combined as this leads to models with high predictive power while reducing the sensitivity to choices made in the modeling process. The inferred distribution model of Caulerpa cylindracea shows the potential for this species to further spread along the coasts of Western Europe, western Africa and the south coast of Australia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Africa, Western
  • Australia
  • Ecosystem
  • Europe
  • Introduced Species*
  • Models, Biological
  • Seaweed / physiology*

Grants and funding

Funding was provided by the Australian Research Council (FT110100585 to HV, LP0882109 and LP0991083 to CFDG), Research Foundation–Flanders, the AXA Research Fund (to FM), the Adelaide & Mt Lofty Ranges Natural Resource Management Board, the Australian Census of Coral Reef Life and the Australia Biological Research Study (ABRS 209-62 to CFDG). LT is a doctoral fellow of the Agency for Innovation by Science and Technology (IWT). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.