What are Biological Invasions?


  • Biological invasions are currently one of the main factors threatening biodiversity at a global scale (Mack et al. 2000). The impact of biological invasions is so large that they are considered the third most important problem affecting ecosystems, after habitat destruction and anthropogenic changes in the atmosphere and the oceans. Their consequences can be the loss of native biodiversity and crops, and the deterioration of land productivity (Mack et al.2000, Stohlgren et al. 2001, Sykes 2001).
  • This is not a new problem for Chile. Numerous species are causing losses at a productive level, or are a threat to the conservation efforts in the country (Arroyo et al.2000, Pauchard et al.2004, Figueroa et al.2004).
  • Understanding the dynamics between native ecosystems and introduced species will allow a better management of their invasions.

Key factors in the process of invasion:



Detail of the interaction between ecosystem attributes and the success of invasive species






Exotic or introduced species: Species whose presence in a biogeographic region is due to a deliberate or accidental introduction as a consequence of human activities.

Naturalized species: Species that are able to reproduce constantly and to maintain stable populations without the intervention of humans.

Invasive species: Naturalized species that have high reproduction rates and have the potential to spread in a considerable area using natural habitats.


*Adapted from Richardson et al. 2000








Eschscholzia californica





Verbascum thapsus L