Species distribution modelling


Biological communities are showing clear signs of change as a direct result of human induced changes to the global environment.  Many studies, including the Millenium Ecosystem Assessment, have shown that the pressures on the planet are high, with biological drivers of change such as pollution, habitat and climate change, as well as biotic introductions, adversely affecting biological diversity.  Ongoing changes to natural communities highlight the urgent need to record, monitor and report on primary biodiversity.

About the Millenium Assessment

The Millennium Ecosystem Assessment (MA) assessed the consequences of ecosystem change for human well-being.  From 2001 to 2005, the MA involved the work of more than 1 360 experts worldwide.  Their findings provide a state-of-the-art scientific appraisal of the condition and trends in the world’s ecosystems and the services they provide, as well as the scientific basis for action to conserve and use them sustainably. View the Synthesis Report for Biodiversity in PDF format.

 

In the last few decades, with the rise of powerful new statistical models and GIS tools, the development of predictive modelling of species distributions based on known occurrences of primary biodiversity data, has become increasing important.  Ecological niche-modelling has been used to address various issues in ecology, biogeography, and evolution and more recently in conservation biology and climate change research.  It is also a valuable tool in predicting the spread of invasive alien species, risk assessments; risk analysis with the introduction of GMO’s, tracking the spread of diseases, reserve selection, amongst other applications.

Species distribution modelling may be divided into four main steps:

  1. Sourcing data — finding species data and environmental and climatic data to use in the model.
  2. Scenarios — producing scenarios for future species distributions.
  3. Modelling — choosing the correct modelling method which suites your data and testing the results.
  4. Mapping — producing an understandable map of the results of the model.

The South African Biodiversity Information Facility (SABIF) has run training courses on species distribution modelling.