Biological Warfare

Within the Garden Route there are numerous alien invasive vegetation species that pose a significant threat to the bio-diversity and ecological balance. These invasive species outcompete native plants, disrupt ecosystems, increase the threat and intensity of wild fire and lead to severe environmental and economic consequences. One effective strategy in combating these invasives is biological control, that involves the use of the invasive species natural enemies to weaken and reduce the population.

Chemical herbicides, whilst essential in combating invasives, if used incorrectly, can harm non-target species, the environment and even the user. Biological control on the other hand is sometimes seen as a safer tool in managing alien invasive vegetation because it offers a sustainable and more environmentally friendly solution. Registered biological control agents, such as specific insects, fungi or pathogens, target only the invasive species. This helps to focus eradication efforts as well as preserve the native flora and fauna, maintaining the ecological integrity.

The introduction of biological control agents is not a new exercise in South Africa and potential agents  must be approached with caution. Rigorous testing is essential prior to release to ensure that the control agents do not become invasive themselves, or unintentionally negatively impact non-target species.

This process involves extensive research and trials, both in quarantine facilities and field conditions, to assess the safety and efficacy of potential control agents. This thorough evaluation helps prevent unintended ecological consequences and ensures that the benefits of biological control outweigh the risks.

The Great Brak River Conservancy has been working alongside various government departments and institutions of higher learning in order to obtain and release biocontrol upon a number of species problematic within our area. These include different gall forming midges for Dragon Fruit as well as  Black Wattle, and a fungus that targets Silky Hakea. It is important to recognise that biological control is not an instant quick fix. It is a gradual process that requires time to establish and effectively reduce the population of invasive species.

Biological control should be viewed as one component of an integrated management strategy, which includes mechanical removal, chemical treatments, and habitat restoration. Combining these methods can provide a more comprehensive and effective approach to managing invasive vegetation.

Through careful testing and integration with other management practices, biological control offers a promising solution to protect South Africa’s rich biodiversity and ecological health from the threats posed by invasive species.