When humans transport species around the globe, either purposefully or accidentally, we commonly do not transport the species' natural, co-evolved enemies. This factor occasionally permits a species to grow and reproduce with substantially more vigor, often to the detriment of natural communities in the species' new home.
Bio-control is the practice of introducing a species' natural enemies to restore the natural checks and balances of the co-evolved species interaction.
Where bio-control was once the foolish practice of haphazardly introducing possible competitive species (think Asian Lady Beetle), it is now a carefully researched and controlled science. Potential bio-control agents are carefully selected to ensure host specificity and minimize risk of non-target impact.
Bio-control agents are currently approved and available for the following invasive species: