Introduction to Alien Invasive Species.
“If we give our very best to all the children of today, and if we pass on our planet in the fullness of her beauty and natural richness, we will be serving the children of the future” ~Nelson R Mandela
WHAT ARE ALIEN INVASIVE SPECIES (A.I.S)?
Species that grow and reproduce quickly, and spread aggressively with potential to cause harm, are given the label of “invasive”. An invasive species can be any kind of living organism – an amphibian, plant, insect, fish, fungus, bacteria or even an organism’s seeds or eggs that is not native to an ecosystem and which causes harm.
They are the biggest threat to plant and animal biodiversity: they have become established in over 10million hectares of land in South Africa, and the cost of controlling them is estimated at R600 million a year over 10 years.
WHY ARE A.I.S. SUCH A THREAT TO THE ENVIRONMENT?
The impacts of alien invasive species are immense, insidious and usually irreversible. They may be as damaging to native species and ecosystems on a global scale as the loss and degradation of habitats.
WHERE DO INVASIVE SPECIES SOME FROM?
Thousands of alien species have been introduced into the country over the past 350 years, and hundreds of them have become invasive.
WHAT ARE THE CONSEQUENCES OF INVASIVE SPECIES?
They reduce water supplies, increase erosion, exacerbate wildfires, degrade valuable range lands, threaten the health of people and livestock, reduce productivity in agriculture, and impact negatively on our remarkable biodiversity. The economic damage caused by these invasions has been estimated at billions of Rands per year, and is set to grow as invasive species spread, and as more species are introduced and become invasive. The heavy use of chemical pesticides, insecticides and herbicides to control invasive pests has in itself had detrimental consequences to ecosystems across the world, leading to pollution of soil and water, as well as causing harm to plants, animals and people working in the fields.
WHAT CAN BE DONE TO STOP THE SPREAD OF A.I.S.?
- Promote the planting of indigenous species, or safe exotic species that have stood the test of time.
- Eradicate and control invasive introduced species and possible replace with in suitable indigenous plants
- Reduce the rate of spread of invasives and reduce the impacts of existing invasions
- Gain support of individuals, organizations and businesses in the private and public sectors.
- Create awareness of the problem of A.I.: the risks associated with any activity involving biological invasions, the legal requirements that regulate the ownership, cultivation, trade and transport of alien species.