Biological Control Risks and Invasive Species

Invasive species pose a threat to wildlife and ecosystems. Biological control, the introduction of natural enemies of such species, is an effective way of reducing the number of invasive species in an area and averting their negative effects. As control agents are usually released in ecosystems that provide good habitat conditions for the species, overpopulation and establishment of the control agents in the area can occur, which may be associated with species extinction and negative impacts on biodiversity in the affected ecosystems. It should be noted, however, that there are many success stories and that there is government oversight of biological control. The main concern is to be aware of the negative impacts that biological control agents can have on other species.

Nº 117

Hawaii

some attempts made
past case
Region-1
Region-2
Region-3
Region-4
ongoing case
no attempts made

Biological Control Risks and Invasive Species

Invasive species pose a threat to wildlife and ecosystems. Biological control, the introduction of natural enemies of such species, is an effective way of reducing the number of invasive species in an area and averting their negative effects. As control agents are usually released in ecosystems that provide good habitat conditions for the species, overpopulation and establishment of the control agents in the area can occur, which may be associated with species extinction and negative impacts on biodiversity in the affected ecosystems. It should be noted, however, that there are many success stories and that there is government oversight of biological control. The main concern is to be aware of the negative impacts that biological control agents can have on other species.

22% of biocontrol agents introduced in Hawaii have been found to feed on non-target species, with varying degrees of impact. The small Indian mongoose was introduced to the island to control rats that threatened sugar cane. But the animals also preyed on native birds. Similarly, the rosy wolf snail, introduced to control populations of the giant African snail, also affected the endemic tree snail.

Invasive-species.org states that in the U.K., proposed biological control agents are only introduced after rigorous testing and reflection, to ensure a safe introduction. Internationally accepted safety testing procedures exist that help demonstrate that the organism under consideration of being introduced will not be harmful to the native ecosystem. This is the preferred method for the use of biological control agents. 

Messing, R. H., & Wright, M. G. (2006). Biological Control of Invasive Species: Solution or Pollution? Frontiers in Ecology and the Environment, 4(3), 132–140. http://www.jstor.org/stable/3868683

Myers, J. H., & Cory, J. S. (2017). Biological control agents: invasive species or valuable solutions?. Impact of biological invasions on ecosystem services, 191-202. https://doi.org/10.1007/978-3-319-45121-3_12