Let’s chat about invasive species. Invasive species are exactly that – any species that doesn’t naturally occur in an area, whether that be plants or animals. Another characteristic of these guys is that they usually cause harm to the environment, economy, or human health – long story short, we’re not a big fan.
Management & introduction of invaders
After many years, the only way we’ve managed to keep these troublesome thieves in check is through preventing new introductions, detecting them early, and responding to them rapidly. Being foreign to the areas they invade, running rampant and taking over is particularly easy for these species because they don’t have any natural predators or competitors – a very smart strategy indeed!
This added advantage of theirs is one of the reasons we make use of protected areas to keep them in check. Protected areas go hand-in-hand with limiting human activities, and unfortunately as is the case with many issues in our environment, we create the PERFECT conditions for these plants and animals to arrive and thrive – and a lot of them wouldn’t even be here without us...
Blue Gums are one such species that we brought along with us from our worldly travels. Originating in Australia, they are massive consumers of water and outcompete a lot of our indigenous forestry.
One of the other strengths of invasive plants over endemic ones is that a lot of them can grow very well in disturbed or nutrient-deficient soil, so any of our activities that disturb the soil (such as mining) unsettle the natural vegetation and give these invaders a head start.
PREVENTION & Early detection
We have many trade and transport regulations in place to control what comes into our country, one of them being the National Environmental Management: Biodiversity Act (Act No. 10 of 2004). This legislation regulates the import, export, and introduction of any biological material into South Africa, including plants and animals that may become invasive.
Biological surveys, genetic testing, and early warning systems such as satellite imagery and drones are some of the ways we detect these species early before they become fully rooted in our soil. The advancement of modern technology has luckily made early detection much easier.
Another way to keep our foreign species in check – and our personal favourite – is public education and outreach. The management of invasive species IS one of the topics we cover in our 6 lessons when we teach schools about conservation and why it’s so crucial.
"Education is the most powerful weapon which you can use to change the world"
control & ERADICATION
The reason why detecting these species early is so important is so we can prevent them from becoming established, because once they’re established they can be tough little pests to get rid of. Although it’s a lot of work, when done properly physical removal is very effective.
Another really effective option is biological control by introducing a natural predator that can do our job for us – the Gall-Forming Wasp does this job incredibly well in controlling the Long-Leaved Wattle, an invasive tree species introduced from Australia in the mid-1800s.
The wasp lays its eggs in the stem of the wattle, forming galls or growths that limit the tree’s growth and reproduction. This wise little wasp poses no threat to other plant species or human health and has done a great job of restricting the invasion of these trees.
Although also effective, chemical treatment has a lot of downsides for the health of our environment and tends to work against it rather than with it. Most eradication efforts are effective in their own right, a combination of two or more of these options usually helps us kick these guys to the curb the best.
reinforcement of natural species
It’s all good and well to say goodbye to these pesky pests, but reinforcing the natural species in an ecosystem and stabilizing the soil and other environmental factors is essential. Whether it be by habitat restoration, reforestation, or protection and management of native species, all our work will only be a short fix if we don’t give the endemic species a head start once we weed out their invasive competitors.
Although sneaky and smart, invaders are no match against naturally-occurring species in a healthy and stable environment!
Since 1948, the International Union for Conservation of Nature (IUCN) and the Convention on Biological Diversity have played a crucial role in initiating and supporting invasive species management efforts. Through guidance, funding, and awareness of management and research throughout the globe, we wouldn’t be where we are without them.
what can I do?
As usual, many hands make light work and we like to give you ideas about where we can do our part! Volunteering at or donating to NGOs and organizations focused on conservation and natural resource management, such as The Nature Trust and The Nature Conservancy, allows us to get our hands dirty and our souls refreshed.
These guys work on the ground to implement control and eradication efforts, provide education and outreach, and advocate for policies and regulations that support invasive species management.
We can also reduce our own impact by avoiding buying and transporting any invasive species, reporting any sightings of invasives, and participating in our own control and eradication efforts. Here are some tips on how to tell if a plant might be invasive:
They’re very fast growers
They spread very quickly
You’ll see them growing all over in all sorts of different conditions, especially in soil or areas that are quite disrupted with a good deal of erosion
They will look quite different to their surrounding native counterparts
Although all plants are competitive, these guys are very aggressive and often strangle or shade native plants to hog all the resources
By working together and holding ourselves accountable, we can reduce the impact of invasive species and protect the economy, the environment, and all her children.
the extra mile
Help us go the extra mile. Each donation allows us to continue our mission of educating to empower, setting the hearts of the next generation of conservationists on fire. You can make a difference today – help us change the world by donating here.